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1.
Aging Clin Exp Res ; 35(10): 2165-2172, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37505395

RESUMEN

BACKGROUND: Dysphagia, or swallowing disorders, has become a growing concern due to the aging population, and health literacy plays a crucial role in active aging. However, the relationship between them remains unclear. AIMS: To investigate the association between health literacy and dysphagia among community-dwelling older adults in China. METHODS: A survey was conducted on 4462 older adults aged 65 and above in a community in Yiwu City, China, from May 2021 to January 2022. Swallowing problems were assessed using a 30 ml water swallowing test (WST) and the Eating Assessment Tool-10 questionnaire (EAT-10). The participants' health literacy was evaluated using the Chinese Health Literacy Scale (CHLS). Logistic regression and t tests were employed to measure the association between them. RESULTS: The prevalence of dysphagia was 5.70% and 7.85% as determined by EAT-10 and 30 ml-WST, respectively. The health literacy level of community-dwelling older adults was 24.4 ± 4.93 (9-45). Participants with dysphagia exhibited lower levels of health literacy (p < 0.05). The logistic regression model demonstrated an inverse association between health literacy and dysphagia (OR = 0.94, 95%CI = 0.91-0.96 for EAT-10, and OR = 0.93, 95%CI = 0.92-0.95 for WST). Moreover, this association remained significant even after adjusting for covariates. DISCUSSION: Older adults with dysphagia have lower levels of health literacy, particularly in terms of their ability to seek medical advice, acquire and evaluate medical information, and access social support resources. CONCLUSIONS: Health literacy is associated with dysphagia among community-dwelling older adults. Effective interventions should be implemented to provide support in terms of both medical services and social support for this population.


Asunto(s)
Trastornos de Deglución , Alfabetización en Salud , Humanos , Anciano , Trastornos de Deglución/epidemiología , Vida Independiente , Estudios Transversales , Envejecimiento
2.
Geriatr Nurs ; 54: 258-263, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37897931

RESUMEN

BACKGROUND: Dysphagia is a health concern that causes severe complications and affects the life quality of the older population. This study aimed to determine the diagnostic performance of the Eating Assessment Tool (EAT)-2 compared with the EAT-10 and the Water Swallow Test (WST) in screening for dysphagia. METHODS: A cross-sectional study was conducted among 5,090 community-dwelling older adults. Dysphagia was evaluated using both a subjective measure, the 10-item EAT (EAT-10) and an objective measure, the WST. The kappa index in pairs were analyzed. The validity and reliability of EAT-2 were also assessed. RESULTS: The sensitivity and specificity of the EAT-2 were 96.3 % and 94.8 %, respectively. The kappa index between the EAT-2 and EAT-10 was 0.64, whereas it was 0.11 between the EAT-10 and WST. CONCLUSIONS: The EAT-2 was a simpler screening tool for dysphagia. Combining the subjective questionnaire (EAT-10 or EAT-2) and the objective test (WST) is recommended.


Asunto(s)
Trastornos de Deglución , Humanos , Anciano , Trastornos de Deglución/diagnóstico , Vida Independiente , Estudios Transversales , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
3.
Nanotechnology ; 28(3): 035704, 2017 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-27941221

RESUMEN

Onion-like carbon nanospheres (OCNSs) with an average diameter of 43 nm were produced on a large scale via a combustion method and examined as an anode material for lithium ion batteries. The OCNSs exhibit a remarkable electrochemical cycling behavior and a capacity much higher than that of graphite. The capacity increases significantly with increasing charge-discharge cycles and reaches a value of 178% of the initial value (from 586 mA h g-1to 1045 mA h g-1) after 200 cycles. Further investigation provides unambiguous experimental evidence that such a remarkable capacity increase is related to the stable onion-like structure of the OCNSs and to the existence of large numbers of disordered/short graphitic fragments, which gradually provide more active sites for Li ion storage. The unique electrochemical performance of OCNSs provides a new way to design a high-performance anode material for rechargeable batteries.

4.
J Nanosci Nanotechnol ; 17(4): 2791-795, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29667808

RESUMEN

Nano/submicro vanadium dioxide rods in monoclinic phase (VO2 (M)) were synthesized through hydrothermal reaction combined with subsequent calcinations. The morphology and structure of samples were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The average diameter of VO2 (M) dioxide rods from 210 nm to 1 µm were successfully controlled by adjusting the synthesis conditions including the concentration of Vanadium pentoxide (V2O5) solution and the molar ratio of V2O5 and oxalic acid. Our results reveal that the concentration of V2O5 is the key factor to determine the diameter of VO2 (M) rods, while higher molar ratio favors formation of VO2 rods with narrow diameter distributions. The growth mechanism of vanadium dioxide rods was discussed.

5.
J Nanosci Nanotechnol ; 15(6): 4058-69, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26369013

RESUMEN

In this study, three types of galactosylated cholesterol (i.e., gal-PEG194-chol, gal-PEG1000-chol and gal-PEG2000-chol) were synthesized with one terminal of polyethylene glycol of various chain lengths conjugated to the galactoside moiety, and the other terminal conjugated to the cholesterol. The galactose-modified liposomes were prepared by thin film-hydration method and doxorubicin (DOX) was loaded to the liposomes by using a ammonium sulfate gradient procedure. The liposomal formulations with galactosylated cholesterol were characterized. Flow cytometry and laser confocal scanning microscopy analyses showed that the galactose-modified liposomes facilitated the intracellular uptake of liposomes into HepG2 via asialoglycoprotein receptor (ASGP-R) mediated endocytosis. Cytotoxicity assay showed that the cell proliferation inhibition effect of galactose-modified liposomes was higher than that of the unmodified liposomes. Additionally, the study on frozen section of liver showed that the galactose-modified liposomes enhanced the intracellular uptake of liposomes into hepatocytes. Taken together, these results suggested that liposomes containing such galactosylated cholesterol (i.e., gal-PEG-chol), had a great potential as drug delivery carriers for hepatocyte-selective targeting.


Asunto(s)
Colesterol/análogos & derivados , Galactosa/química , Hepatocitos/metabolismo , Liposomas/química , Polietilenglicoles/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Receptor de Asialoglicoproteína/metabolismo , Proliferación Celular/efectos de los fármacos , Colesterol/química , Colesterol/farmacocinética , Colesterol/toxicidad , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Células HeLa , Células Hep G2 , Humanos , Liposomas/farmacocinética , Liposomas/toxicidad , Hígado/química , Hígado/metabolismo , Ratones , Polietilenglicoles/farmacocinética , Polietilenglicoles/toxicidad , Distribución Tisular
6.
Nurs Open ; 11(6): e2172, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38837592

RESUMEN

AIMS: To explore the knowledge, attitudes and practice status of the intrahospital transport (IHT) of critically ill patients among clinical nurses and their influencing factors. DESIGN: Cross-sectional study. METHODS: A questionnaire determined the nurses' knowledge, attitudes and practice scores. The questionnaire was used for data collection in a tertiary hospital from 10 January to 17 January 2023. Multivariate regression analysis was also used to evaluate the related factors of IHT of critically ill patients in different dimensions. RESULTS: Out of 670 distributed questionnaires, 612 nurses returned the completed questionnaire. The scores of KAP were (9.72 ± 1.61), (42.91 ± 4.58) and (82.84 ± 1.61), respectively. Pearson's correlation analysis showed that knowledge, attitude and behaviour scores were positively correlated. Variables that were associated with the scores of transfer knowledge were the scores of transfer practice, different departments and the scores of transfer attitude. The score of practice, number of IHT and received hospital-level training had statistical significance on the nurses' attitude scores. Furthermore, the score of the attitude and transport knowledge had statistical significance on the nurses' practice. CONCLUSION: The findings indicate a clear need for clinical nurses' knowledge of IHT of critically ill patients, especially in the emergency department (ED) and ICU. In addition, nurses need to be more active in transporting critically ill patients. Managers should enhance nurses' confidence in the IHT of critically ill patients and promote clinical nurses to establish a correct and positive attitude. IMPACT: The findings of this study benefit nursing managers in understanding the current situation of IHT of critically ill patients. Managers should apply new training methods to nursing education and develop a multi-level training program that is systematic, comprehensive and demand-oriented. PATIENT OR PUBLIC CONTRIBUTION: The participants of this study were nurses and this contribution has been explained in the Data collection section. There was no patient contribution in this study.


Asunto(s)
Enfermedad Crítica , Conocimientos, Actitudes y Práctica en Salud , Humanos , Estudios Transversales , Femenino , Masculino , Adulto , Encuestas y Cuestionarios , Actitud del Personal de Salud , Transferencia de Pacientes/estadística & datos numéricos , Personal de Enfermería en Hospital/psicología
7.
Eur Geriatr Med ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842653

RESUMEN

PURPOSE: Numerous epidemiological studies have suggested a possible association between dysphagia and the risk of decline in Activities of daily living (ADL) among older adults. This systematic review and meta-analysis aimed to elucidate the relationship between dysphagia and ADL in older adults. METHODS: PubMed, Web of Science, Cochrane Library, Embase, Ebsco, MEDLINE, Wiley, CINAHL, and Ovid databases were comprehensively examined for relevant studies published up to October 31, 2022. Quantitative studies published in English were included to explore the relationship between dysphagia and ADL in people aged 65 years and older. The NIH Quality Assessment Tool was used to assess the study quality. R software was used to draw forest plots and I2 was employed to indicate study heterogeneity. Sensitivity analysis was performed using the one-by-one exclusion method. Publication bias was measured using funnel plots and Egger's test. RESULTS: A total of 3,498 studies were retrieved from the database, 22 of which were eventually included in the systematic evaluation, and 14 of which were subjected to meta-analysis. Data from nine studies were categorical variables, and meta-analysis results showed that swallowing disorders in older adults were associated with a lower ability to perform ADL (OR = 3.39, 95% CI: 2.55-4.50, p < 0.001), with moderate heterogeneity (I2 = 62%, p = 0.006). Data from seven studies were continuous variables, resulting in a negative association between the prevalence of dysphagia and ADLs in older adults (SMD = -0.80, 95% CI: -1.08 to -0.51, p < 0.001), with high heterogeneity (I2 = 94%, p < 0.001). Sensitivity analysis showed robust results, funnel plots and Egger's test indicated no publication bias. CONCLUSION: Dysphagia is significantly associated with the capacity to perform ADL. Prevention and screening of dysphagia in older patients dependent on others for daily care are needed. Further long-term studies are needed in the future to prove causality.

8.
J Multidiscip Healthc ; 17: 3073-3090, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974375

RESUMEN

Background: In recent years, research on dysphagia has gained significant traction as one of the key topics of oral health research pertaining to the aged. Numerous academics have studied dysphagia in great detail and have produced numerous excellent scientific research findings. Objective: To review the literature regarding dysphagia in community-dwelling older adults and identify the knowledge and trends using bibliometric methods. Methods: The literature on dysphagia in older adults in the community was gathered from the Web of Science Core Collection (WoSCC), with inclusion criteria specifying English-language publications. The retrieval deadline was November 28, 2022. We extracted the following data: title, year, abstract, author, keywords, institution, and cited literature, and used CiteSpace (version 6.1.R3) to visualize the data through the knowledge map, burst keyword analysis, cluster analysis, and collaborative network analysis. Results: A total of 979 articles and reviews were retrieved. Regarding productivity, the top 2 countries were the United States (n =239) and Japan (n =236). Hidetaka Wakabayashi (n =26) was one of the most prolific writers. The first paper in the frequency ranking of references cited was a white paper: European Society for Swallowing Disorders and European Union Geriatric Medicine Society white paper: oropharyngeal dysphagia as a geriatric syndrome (n =53). "Prevalence" (n =173), "risk factor" (n =119), and "aspiration pneumonia" (n =108) were the most frequently occurring keywords (excluding defining nouns). The study identified reliability, tongue pressure, home discharge, and swallowing function as research hotspots from 2020 to 2022. Conclusion: Prevalence, risk factors, and pneumonia are significant areas of study. Tongue pressure and sarcopenia are research hotspots and potential targets. In the future, research on dysphagia needs to refine strategies for prevention and control, as well as provide tertiary preventative services.

9.
Am J Prev Med ; 66(3): 559-567, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37844711

RESUMEN

INTRODUCTION: Intrinsic capacity (IC), a composite of physical and mental capacities, is a marker of healthy aging. Social determinants of health (SDOH), namely the economic and social environments across a lifespan, are the most fundamental factors influencing health outcomes and health disparities. However, there is limited evidence on the influence of the individual and combined burden of the SDOH on IC. METHODS: Data were obtained from the China Health and Retirement Longitudinal Study (2011-2015), and data analysis was conducted in 2023. Linear mixed-effect regression was employed to investigate the association between SDOH and IC in a longitudinal analysis. RESULTS: This study comprised 7,669 participants (mean [SD] age, 68.5 [7.1] years; 49.8% female; mean [SD] IC, 7.2 [1.6]). In the longitudinal analysis, all five SDOH domains were independently and significantly associated with IC. The absence of social association within the social and community context domain exhibited the weakest association with IC (ß: -0.11 [95% CI -0.20, -0.02]), while illiteracy within the education access and quality domain demonstrated the strongest association with IC (ß: -0.51 [95% CI -0.60, -0.42]). Furthermore, the adverse effects of SDOH on IC became more distinguishable with the cumulative number of SDOH variables (coefficient for 2 SDOH, -0.41 [-0.64, -0.19]; 3 SDOH, -0.70 [-0.93, -0.48]; ≥4 SDOH, -1.10 [-1.33, -0.88]) compared with those without any SDOH. CONCLUSIONS: Certain SDOH levels were significantly and negatively associated with IC. Targeted interventions may be needed to improve SDOH in individuals at high risk of poor IC.


Asunto(s)
Análisis de Datos , Determinantes Sociales de la Salud , Humanos , Femenino , Anciano , Masculino , Estudios de Cohortes , Estudios Longitudinales , China
10.
Sci Total Environ ; 859(Pt 1): 160284, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36403831

RESUMEN

Nanomaterials-based photoelectrochemical (PEC) detection is becoming a rapidly-developing analytical technique in chemical and biological assays due to its unique advantages of easy miniaturization, high sensitivity, and rapid turnaround time. Herein, a molecularly imprinted polymer-assisted PEC sensor based on ZnO/C nanocomposite was successfully fabricated for the highly sensitive and selective determination of chloramphenicol (CAP). Benefiting from the hydrophilic functional groups (-OH, -COOH) and large surface area of bio-templated ZnO/C nanocomposite, the tight grafting of MIP with excellent recognition ability on substrate is easier and more stable than traditional PEC sensor, thus significantly increasing the performance. Under optimal conditions, the PEC sensor exhibited significant CAP detection performance in the range of 0.01-5000 ng mL-1 with a detection LOD of 5.08 pg mL-1 (S/N = 3) and successfully applied to the detection of CAP in milk sample. Our results show that ZnO/C nanocomposite and MIP can act as an efficient photo-responsible matrix to fabricate PEC sensor, providing important application potentials for pollutants control in food and environment.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Nanocompuestos , Cloranfenicol , Impresión Molecular/métodos , Técnicas Electroquímicas/métodos , Polímeros Impresos Molecularmente , Límite de Detección , Técnicas Biosensibles/métodos
11.
Heliyon ; 9(5): e15609, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37144193

RESUMEN

Background: Liver diseases are a spectrum of diseases that include hepatic steatosis, nonalcoholic fatty liver disease, hepatitis, liver fibrosis, cirrhosis, and hepatic cancer. These diseases not only severely decrease the quality of life for patients, but also cause financial burden. Although apigenin (APG) has recently become the primary treatment for liver injuries and diseases (LIADs), there has been no systematic review of its use. Purpose: To review the existing literature and put forward novel strategies for future APG research on LIADs. Methods: A search was conducted in PubMed, Science Direct, Research Gate, Web of Science, VIP, Wanfang, and CNKI, and 809 articles were obtained. After applying inclusion and exclusion criteria, 135 articles were included. Results: APG is promising in treating LIADs via various mechanisms arising from its anti-inflammation, anti-proliferation, anti-infection, anti-oxidation, and anti-cancer properties. Conclusion: This review summarizes the evidence supporting the use of APG as a treatment for LIADs and provides an insight into the intestinal microbiota, which may have important implications in its future clinical use.

12.
Med Ultrason ; 25(3): 263-269, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37778020

RESUMEN

AIM: Adenomyoma is an exceptionally rare hamartoma in the small intestine. Few data have been reported on the features of this rare disease. The aim of this study was to describe the ultrasound (US) characteristics of small intestinal adenomyomas. Material and methods: This retrospective study analyzed the clinical features and US data of 15 pediatric patients diagnosed as small intestinal adenomyomas in the age range between 1 day to 12 years in our hospital during 2014-2021. RESULTS: The clinical manifestations of all the small intestinal adenomyomas were abdominal pain, vomiting or/and hemafecia. The small intestinal adenomyoma usually acted as the lead point of secondary intussusception. They were identified in the ileum (n=11), jejunum (n=2), and Meckel's diverticulum (n=2). The diagnostic accuracy (the concordance rate between US diagnosis and pathological diagnosis) of small intestinal adenomyoma was 73.3%. The small intestinal adenomyoma had approximately 1.0-3.0 cm, were typically located in the submucosal region, had the basal part wide and without a pedicle, and its boundaries were clear. The mass protruded into the intestinal cavity, and showed oval hypoechoic polycystic echo nodules, containing multiple small quasi-circular or irregular cysts of different sizes surrounded by solid hypoechoic mosaic areas. The color Doppler US showed in the solid hypoechoic areas of the mass abundant or sparse blood flow signals.Conclusions The US findings of small intestinal adenomyomas in children are characteristic, and US is valuable in the identification of intestinal adenomyomas in children.


Asunto(s)
Adenomioma , Divertículo Ileal , Humanos , Niño , Recién Nacido , Adenomioma/diagnóstico por imagen , Adenomioma/complicaciones , Adenomioma/patología , Estudios Retrospectivos , Divertículo Ileal/complicaciones , Ultrasonografía , Ultrasonografía Doppler en Color
13.
Food Chem ; 426: 136535, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37331139

RESUMEN

Antibiotic monitoring remains vital to ensure human health and safety in the environment and foods. As the most popular detection method, photoelectrochemical (PEC) sensor can achieve rapid and accurate detection of antibiotics with the advantages of high sensitivity, easy-to-preparation process, as well as high selectivity. Herein, an extremely-efficient visible-light responsible ZnO/C nanocomposite was prepared and combined with acetylene black (as an enhanced conductive matrix), and the electron migration efficiency was greatly accelerated. Meanwhile, a molecularly imprinted polymer obtained by electrical agglomeration was conjugated as a specific recognizing site for target. Furthermore, the as-prepared rMIP-PEC sensor showed a low detection limit (8.75 pmol L-1, S/N = 3) in a wide linear detection range of 0.01-1000 nmol L-1 for oxytetracycline (OTC), with excellent selectivity and long-term stability. Our work shed light on applying C-doped ZnO semiconductor and molecularly imprinted polymer as photoelectric active sensing materials for rapid and accurate analysis of antibiotics in foods and environment.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Nanocompuestos , Oxitetraciclina , Óxido de Zinc , Humanos , Animales , Oxitetraciclina/análisis , Polímeros Impresos Molecularmente , Leche/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Antibacterianos/análisis , Límite de Detección , Impresión Molecular/métodos
14.
ACS Appl Mater Interfaces ; 15(24): 29178-29185, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37279435

RESUMEN

Poor stability retards the industrialization of perovskite solar cells (PSCs). One of the effective ways to solve this issue is to modify the perovskite surface to improve the efficiency and stability of the PSCs. Herein, we synthesized CuFeS2 nanocrystals and applied them to modify the perovskite surface. The efficiency of the PSCs with CuFeS2 modification is improved to 20.17% from 18.64% for the control devices. Some investigations demonstrate that the CuFeS2 modification passivates the perovskite surface defects and induces better energy band arrangement. Furthermore, the stability of the PSCs with CuFeS2 modification is improved compared with the devices without CuFeS2 modification. The efficiency of the PSCs with CuFeS2 modification maintains 93% of its initial value, whereas that of the devices without CuFeS2 modification decreases to 61% of the initial value. This work demonstrates that CuFeS2 is a novel material used as a modification layer to enhance the efficiency and stability of the PSCs.

15.
Nurs Open ; 10(4): 2376-2391, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36440605

RESUMEN

AIM: To develop a set of evidence-informed strategies to assist older people to improve swallowing functions and prevent further damage from complications. DESIGN: A two-round Delphi survey. METHODS: An initial set of dysphagia care strategies with 74 relevant items for older people was formed based on a literature review by seven researchers. An online survey was conducted by 21 panellists, and data of experts' opinions were collected and analysed by improved Delphi method. RESULTS: The positive coefficients in the two rounds of expert consultation were 85.71% and 83.33%, respectively. Consensus was reached with 53 items included and was allocated into the following five sections: (1) screening, (2) assessment, (3) training, (4) interventions and (5) management. These strategies were named with the acronym of each section-"SATIA". The management strategy can be applied to guide the management of older people with dysphagia.


Asunto(s)
Trastornos de Deglución , Humanos , Anciano , Consenso , Técnica Delphi , Encuestas y Cuestionarios
16.
Nanoscale ; 14(11): 4263-4270, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35244135

RESUMEN

Lead halide perovskite quantum dots (PQDs) are extremely unstable when exposed to oxygen, water and heat, especially red CsPbBrxI3-x (x = 0, 0.5, 1.2) PQDs. This seriously hinders their practical application. Here, red CsPbBrxI3-x (x = 0, 0.5, 1.2) PQDs have been successfully encapsulated in porous CaF2:Ce,Tb hierarchical nanospheres (HNSs), which not only greatly improved the stability of PQDs, benefitting from the protection of the CaF2 shell, but also maintained the high photoluminescence quantum yield (PLQY) of PQDs, benefitting from the sensitization of Tb3+ ions. More importantly, porous CaF2:Ce,Tb nanoarchitectures can prevent aggregation quenching and anion exchange of PQDs. Therefore, the CaF2:Ce,Tb&CsPbBrxI3-x (x = 0, 0.5, 1.2) composite powder can have high PLQY comparable to that of the PQD powder. In view of this, CaF2:Ce,Tb&CsPbBr1.2I1.8 composite based red light-emitting diodes (LEDs) are prepared, and they are very suitable as a supplementary light source for plant lighting. Furthermore, white LEDs are also prepared by coating the CaF2:Ce,Tb&CsPbBr3 and CaF2:Ce,Tb&CsPbBr1.2I1.8 composite on a 450 nm chip. The optimum luminous efficiency is 61.2 lm W-1, and the color rendering index is 91, which are comparable to the current highest values. This shows that the composite composed of PQDs has great potential in LED lighting.

17.
Bioinspir Biomim ; 18(1)2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36322980

RESUMEN

A bee's tongue is coated in dynamic hairs that gradually unfold to entrain the viscid nectar, during which hairs inevitably deflect as a result of fluid drag. The hair deflection induced decline in nectar capture rate may be a coupled elastoviscous problem and remains poorly understood. Here we employed geometric beam theory coupled with the effective viscous force to derive a dynamic model for a rotary tongue hair deflection in a viscous fluid. Considering deflection of the tongue hair, we rationalized the nectar capture rate by takingBombusterrestrisas a model system. When the nectar concentration increases from 20% to 70%, the nectar capture rate declines by 87%, indicating that hair erection is more severely impeded in thicker nectar. Based on this model, we predicted an optimal hair length with which the bee can reach the maximum nectar capture rate. This work may provide a new theoretical framework for quantifying viscous liquid transport by hairy surfaces and shed light on design methodologies for fluid transport devices using hairy beds.


Asunto(s)
Néctar de las Plantas , Lengua , Abejas , Animales , Viscosidad , Cabello , Modelos Biológicos
18.
Clin Nutr ; 41(12): 2720-2728, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36368257

RESUMEN

BACKGROUND & AIMS: Metal exposure is suspected to be associated with the risk of chronic kidney disease (CKD). Copper (Cu) is an essential yet toxic trace element in humans. Epidemiological evidence on the association of Cu exposure with CKD remains inconsistent. This study aims to investigate the association of blood Cu and its co-exposure to other metals with CKD. METHODS: A cross-sectional study was conducted among 3285 older participants in Zhejiang, China. The whole blood levels of Cu as well as other 10 metals were measured using the inductively coupled plasma mass spectrometry (ICP-MS). CKD events were defined as the presence of albuminuria or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. Multivariable logistic regression and linear regression models were applied to assess the association of Cu with kidney function. The Bayesian kernel machine regression (BKMR) was used to examine the association of metal interactions with CKD. RESULTS: In logistic models, we found a dose-dependent positive association between blood Cu and the prevalence of CKD. Compared to the lowest quartile of blood Cu, the odds ratio (OR) of CKD in the highest quartile was 1.65 (95% confidence interval, CI: 1.25, 2.17), and the ß of eGFR was -1.74 (95% CI: -3.15, -0.34) after adjusting for multiple covariates. The positive linear dose-response association was found between blood Cu and the OR of CKD, and negative linear association was found between Cu and the ß of eGFR. The positive association between blood Cu and CKD risk was stronger at lower level of manganese (Mn) in the BKMR model. CONCLUSION: The whole blood level of Cu was remarkably associated with the risk of CKD and showed positive dose-response relationships in the older Chinese population. The toxicity of Cu on kidney function could be antagonized by the exposure of Mn. These findings shed new light on the potential role of Cu in kidney health.


Asunto(s)
Cobre , Insuficiencia Renal Crónica , Humanos , Anciano , Prevalencia , Estudios Transversales , Teorema de Bayes , Tasa de Filtración Glomerular
19.
ACS Appl Mater Interfaces ; 13(2): 2674-2684, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33399466

RESUMEN

Extending photoelectric response to the near-infrared (NIR) region using upconversion luminescent (UCL) materials is one promising approach to obtain high-efficiency perovskite solar cells (PSCs). However, challenges remain due to the shortage of highly efficient UCL materials and device structure. NaCsWO3 nanocrystals exhibit near-infrared absorption arising from the local surface plasmon resonance (LSPR) effect, which can be used to boost the UCL of rare-earth-doped upconversion nanoparticles (UCNPs). In this study, using NaCsWO3 as the LSPR center, NaCsWO3@NaYF4@NaYF4:Yb,Er nanoparticles were synthesized and the UCL intensity could be enhanced by more than 124 times when the amount of NaCsWO3 was 2.8 mmol %. Then, such efficient UCNPs were not only doped into the hole transport layer but also used to modify the perovskite film in PSCs, resulting in the highest power conversion efficiency (PCE) reaching 18.89% (that of the control device was 16.01% and the PCE improvement was 17.99%). Possible factors for the improvement of PSCs were studied and analyzed. It is found that UCNPs can broaden the response range of PSCs to the NIR region due to the LSPR-enhanced UCL and increase the visible light reabsorption of PSCs due to the scattering and reflection effect, which generate more photocurrent in PSCs. In addition, UCNPs modify the perovskite film by effectively filling the holes and gaps at the grain boundary and eliminating the perovskite surface defects, which lead to less carrier recombination and then effectively improve the performance of PSC devices.

20.
Chem Commun (Camb) ; 56(93): 14609-14612, 2020 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-33150886

RESUMEN

Herein, a Yb,Tm:NaYF4@NaLuF4/Mn:CsPbCl3 quasi-core/shell heterostructure is synthesized with the assistance of silica. The strong upconverting and downshifting emission of Mn2+ ions was observed in the nanocomposite with a quasi-core/shell structure. The FRET process further improves the energy utilization efficiency of PQDs for UCNPs, which depends on the quasi-core/shell heterostructure. Considering the dual-model fluorescence emission behavior of Mn2+ ions, the stable Yb,Tm:NaYF4@NaLuF4/Mn:CsPbCl3 nanocomposite is used in anti-counterfeiting applications.

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