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1.
Nat Mater ; 23(6): 782-789, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38491147

RESUMEN

Coupling of spin and charge currents to structural chirality in non-magnetic materials, known as chirality-induced spin selectivity, is promising for application in spintronic devices at room temperature. Although the chirality-induced spin selectivity effect has been identified in various chiral materials, its Onsager reciprocal process, the inverse chirality-induced spin selectivity effect, remains unexplored. Here we report the observation of the inverse chirality-induced spin selectivity effect in chiral assemblies of π-conjugated polymers. Using spin-pumping techniques, the inverse chirality-induced spin selectivity effect enables quantification of the magnitude of the longitudinal spin-to-charge conversion driven by chirality-induced spin selectivity in different chiral polymers. By widely tuning conductivities and supramolecular chiral structures via a printing method, we found a very long spin relaxation time of up to several nanoseconds parallel to the chiral axis. Our demonstration of the inverse chirality-induced spin selectivity effect suggests possibilities for elucidating the puzzling interplay between spin and chirality, and opens a route for spintronic applications using printable chiral assemblies.

2.
Alzheimers Dement ; 20(1): 266-277, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37592813

RESUMEN

INTRODUCTION: Research-oriented autopsy cohorts provide critical insights into dementia pathobiology. However, different studies sometimes report disparate findings, partially because each study has its own recruitment biases. We hypothesized that a straightforward metric, related to the percentage of research volunteers cognitively normal at recruitment, would predict other inter-cohort differences. METHODS: The National Alzheimer's Coordinating Center (NACC) provided data on N = 7178 autopsied participants from 28 individual research centers. Research cohorts were grouped based on the proportion of participants with normal cognition at initial clinical visit. RESULTS: Cohorts with more participants who were cognitively normal at recruitment contained more individuals who were older, female, had lower frequencies of apolipoprotein E ε4, Lewy body disease, and frontotemporal dementia, but higher rates of cerebrovascular disease. Alzheimer's disease (AD) pathology was little different between groups. DISCUSSION: The percentage of participants recruited while cognitively normal predicted differences in findings in autopsy research cohorts. Most differences were in non-AD pathologies. HIGHLIGHTS: Systematic differences exist between autopsy cohorts that serve dementia research. We propose a metric to use for gauging a research-oriented autopsy cohort. It is essential to consider the characteristics of autopsy cohorts.


Asunto(s)
Enfermedad de Alzheimer , Trastornos Cerebrovasculares , Enfermedad por Cuerpos de Lewy , Humanos , Femenino , Sesgo de Selección , Enfermedad de Alzheimer/patología , Enfermedad por Cuerpos de Lewy/patología , Autopsia
3.
Medicina (Kaunas) ; 59(1)2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36676717

RESUMEN

Cardiovascular events such as myocarditis following mRNA COVID-19 vaccination are increasing. We present a 67-year-old postmenopausal woman with Takotsubo Syndrome and Graves' disease after mRNA COVID-19 vaccination. She developed chest pain and shortness of breath one week after vaccination. An electrocardiogram revealed ST elevation in the precordial leads. Coronary angiography revealed the absence of obstructive coronary artery disease, and the left ventriculography showed a typical feature with apical ballooning. Laboratory workup showed the elevation of free T4 and thyrotropin receptor antibodies. It was presumed that Takotsubo Syndrome and Graves' disease were probably related to the COVID-19 mRNA vaccination. The patient was treated with low-dose bisoprolol, diuretics, carbimazole, and steroid and discharged uneventfully. The mRNA COVID-19 vaccination is still safe and effective to defend against COVID-19 pandemic. However, clinicians should be aware of the possible cardiovascular adverse events other than myocarditis following vaccination.


Asunto(s)
COVID-19 , Enfermedad de Graves , Miocarditis , Cardiomiopatía de Takotsubo , Femenino , Humanos , Anciano , Vacunas contra la COVID-19/efectos adversos , Cardiomiopatía de Takotsubo/etiología , Pandemias , Enfermedad de Graves/complicaciones , Enfermedad de Graves/tratamiento farmacológico
4.
Brain ; 143(2): 611-621, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31942622

RESUMEN

Primary age-related tauopathy is increasingly recognized as a separate neuropathological entity different from Alzheimer's disease. Both share the neuropathological features of tau aggregates and neuronal loss in the temporal lobe, but primary age-related tauopathy lacks the requisite amyloid plaques central to Alzheimer's disease. While both have similar clinical presentations, individuals with symptomatic primary age-related tauopathy are commonly of more advanced ages with milder cognitive dysfunction. Direct comparison of the neuropsychological trajectories of primary age-related tauopathy and Alzheimer's disease has not been thoroughly evaluated and thus, our objective was to determine how cognitive decline differs longitudinally between these two conditions after the onset of clinical symptoms. Data were obtained from the National Alzheimer's Coordinating Center on participants with mild cognitive impairment at baseline and either no neuritic plaques (i.e. primary age-related tauopathy) or moderate to frequent neuritic plaques (i.e. Alzheimer neuropathological change) at subsequent autopsy. For patients with Alzheimer's disease and primary age-related tauopathy, we compared rates of decline in the sum of boxes score from the CDR® Dementia Staging Instrument and in five cognitive domains (episodic memory, attention/working memory, executive function, language/semantic memory, and global composite) using z-scores for neuropsychological tests that were calculated based on scores for participants with normal cognition. The differences in rates of change were tested using linear mixed-effects models accounting for clinical centre clustering and repeated measures by individual. Models were adjusted for sex, age, education, baseline test score, Braak stage, apolipoprotein ε4 (APOE ε4) carrier status, family history of cognitive impairment, and history of stroke, hypertension, or diabetes. We identified 578 participants with a global CDR of 0.5 (i.e. mild cognitive impairment) at baseline, 126 with primary age-related tauopathy and 452 with Alzheimer's disease. Examining the difference in rates of change in CDR sum of boxes and in all domain scores, participants with Alzheimer's disease had a significantly steeper decline after becoming clinically symptomatic than those with primary age-related tauopathy. This remained true after adjusting for covariates. The results of this analysis corroborate previous studies showing that primary age-related tauopathy has slower cognitive decline than Alzheimer's disease across multiple neuropsychological domains, thus adding to the understanding of the neuropsychological burden in primary age-related tauopathy. The study provides further evidence to support the hypothesis that primary age-related tauopathy has distinct neuropathological and clinical features compared to Alzheimer's disease.


Asunto(s)
Trastornos del Conocimiento/patología , Cognición/fisiología , Disfunción Cognitiva/patología , Tauopatías/patología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Disfunción Cognitiva/diagnóstico , Función Ejecutiva/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Aerobiologia (Bologna) ; 37(2): 243-252, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33462522

RESUMEN

The liquid impingers can be used for sampling of viral aerosols, such as COVID-19 virus, influenza, and measles. However, the lowest cutoff diameter of commercially available liquid impingers was about 0.3 µm, and the physical collection efficiency for nano-bioaerosol is only about 10-20%. Here, we enhanced the impinger's collection efficiency and recovery of viable viral aerosols by using packed glass beads and selected sampling media (1% peptone and lysogeny broth, LB). Single-stranded RNA (ssRNA) MS2 bacteriophage with uranine (as a physical tracer) was used as model viral aerosols. The effects of different sampling flow rates (4, 6, and 12.5 L per minute) and different sampling time (10, 20, and 30 min) on the collection efficiency and recovery of MS2 aerosols were also tested. Collection efficiency and recovery of viable viral aerosols were analyzed as a function of sampling media, flow rate, and sampling time and packed glass beads by using a general linear model. Although the packed glass beads considerably enhanced the collection efficiency of the liquid impinger for MS2 aerosols, the recovery of viable MS2 becomes lower due to the higher pressure drop across the impinger. Using peptone or LB as sampling media, reducing sampling flow rate, and decreasing sampling time was proven to improve the recovery of viable MS2. Conclusively, this study provides some practical methods to improve the collection efficiency of liquid impinger for viral aerosols and preserve their viability.

6.
Alzheimer Dis Assoc Disord ; 34(2): 175-177, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32218065

RESUMEN

The proprietary neuropsychological tests (Form C1) of the National Alzheimer's Coordinating Center (NACC) Uniform Data Set were replaced with nonproprietary versions (Form C2) chosen to closely model their proprietary counterparts. Correlations between analogous test pairs as measured in previous work were good (0.68-0.78), but it is unclear whether the paired tests represent the same set of common factors of cognition or if important factors specific to C1 or C2 only exist. The authors performed multiple factor analysis to analyze correlated C1 and C2 data. They included participants who completed both neuropsychological batteries within 1 year with no change in cognitive status. They found that the C1 and C2 neuropsychological test pairs are strongly related and are represented by the same principal factors. These findings support the use of the C2 test results in conjunction with C1 in longitudinal analyses of NACC data.


Asunto(s)
Enfermedad de Alzheimer , Análisis Factorial , Pruebas Neuropsicológicas/normas , Anciano , Femenino , Humanos , Masculino
7.
Lab Invest ; 99(7): 1049-1055, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30710118

RESUMEN

Primary age-related tauopathy (PART) is increasingly recognized as a pathologic entity distinct from Alzheimer's disease (AD). Given that the diagnosis of PART is an autopsy diagnosis, it is unclear how PART is perceived in clinical practice. Thus, we investigated the presumptive primary and contributing diagnoses in individuals who had cognitive impairment while alive and who met neuropathologic criteria for PART at autopsy. We also compared these clinical diagnoses for people with PART to those with AD neuropathology (ADNP). We used data on 1354 participants from the National Alzheimer's Coordinating Center, restricting to those with no neuritic plaques (PART) or moderate/frequent neuritic plaques (ADNP); clinical visit within two years of autopsy; and mild cognitive impairment (MCI) or dementia at last visit. To assess if PART participants were less likely to receive a clinical diagnosis of AD at their last visit prior to autopsy, we used logistic regression, controlling for age, sex, education, and APOE ε4 status. There were 161 PART individuals (n = 49 MCI; n = 112 dementia) and 1193 individuals with ADNP (n = 75 MCI; n = 1118 dementia). Primary clinical diagnosis of AD was more common in those with ADNP (MCI: 69%; demented: 86%) than PART (MCI: 57%; demented: 52%). In the adjusted analysis, primary and contributing clinical diagnoses of AD remained less likely in PART vs. ADNP participants with dementia (OR: 0.22, 95% CI: 0.13-0.38). This study suggests that clinicians recognize a distinction in the clinical presentation between PART and ADNP, diagnosing AD less frequently in those with PART. Nonetheless, clinical AD was diagnosed greater than 50% of the time in PART participants with MCI or dementia. Ante-mortem criteria for diagnosis of PART need to be established, as PART is a neuropathological entity that is distinct from AD and has its own clinical and cognitive outcomes.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Encéfalo/patología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Disfunción Cognitiva/patología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Placa Amiloide
8.
Langmuir ; 35(9): 3256-3264, 2019 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-30607954

RESUMEN

In this study, a highly responsive humidity sensor is developed by printing gold nanoparticles (GNPs) grafted with a hygroscopic polymer. These GNPs are inkjet-printed to form a uniform thin film over an interdigitated electrode with a controllable thickness by adjusting the printing parameters. The resistance of the printed GNP thin film decreases significantly upon exposure to water vapor and exhibits a semi-log relationship with relative humidity (RH). The sensor can detect RH variations from 1.8 to 95% with large resistance changes up to 4 orders of magnitude with no hysteresis and small temperature dependence. In addition, with a small thickness, the sensor can reach absorption equilibrium quickly with response and recovery times of ≤1.2 and ≤3 s, respectively. The fast response to humidity changes also allows the GNP thin-film sensor to distinguish signals from intermittent humidification/dehumidification cycles with a frequency up to 2.5 Hz. The printed sensors on flexible substrates show little sensitivity to bending deformation and can be embedded in a mask for human respiratory detection. In summary, this study demonstrates the feasibility of applying printing technology for the fabrication of thin-film humidity sensors, and the methodology developed can be further applied to fabricate many other types of nanoparticle-based sensor devices.

9.
Indoor Air ; 29(3): 439-449, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30738001

RESUMEN

A novel antimicrobial composite of zero-valent silver nanoparticles (AgNPs), titania (TiO2 ), and chitosan (CS) was prepared via photochemical deposition of AgNPs on a CS-TiO2 matrix (AgNPs@CS-TiO2 ). Electron microscopy showed that the AgNPs were well dispersed on the CS-TiO2 , with diameters of 6.69-8.84 nm. X-ray photoelectron spectra indicated that most of the AgNPs were reduced to metallic Ag. Fourier-transform infrared spectroscopy indicated that some AgNPs formed a chelate with CS through coordination of Ag+ with the CS amide II groups. The zones of inhibition of AgNPs@CS-TiO2 for bacteria (Escherichia coli and Staphylococcus epidermidis) and fungi (Aspergillus niger and Penicillium spinulosum) were 6.72-11.08 and 5.45-5.77 mm, respectively, and the minimum (critical) concentrations of AgNPs required to inhibit the growth of bacteria and fungi were 7.57 and 16.51 µg-Ag/mm2 , respectively. The removal efficiency of a AgNPs@TiO2 -CS bed filter for bioaerosols (η) increased with the packing depth, and the optimal filter quality (qF) occurred for packing depths of 2-4 cm (qF = 0.0285-0.103 Pa-1 ; η = 57.6%-98.2%). When AgNPs@TiO2 -CS bed filters were installed in the ventilation systems of hospital wards, up to 88% of bacteria and 97% of fungi were removed within 30 minutes. Consequently, AgNPs@TiO2 -CS has promising potentials in bioaerosol purification.


Asunto(s)
Antiinfecciosos/administración & dosificación , Quitosano , Desinfección/métodos , Nanopartículas del Metal , Nanocompuestos/administración & dosificación , Plata , Titanio , Aerosoles , Filtros de Aire , Microbiología del Aire , Antiinfecciosos/química , Unidades Hospitalarias , Nanocompuestos/química , Espectroscopía Infrarroja por Transformada de Fourier , Ventilación/métodos
10.
Artículo en Inglés | MEDLINE | ID: mdl-31177909

RESUMEN

Preschool children have a higher respiratory rate per unit body weight than adults, and their respiratory systems are not mature. Hence, children may have more health risks associated with particulate matter (PM) exposure. In this study, we assessed the exposure of preschool children and their caregivers to PM and the resulting health risks. The PM concentrations at heights of 60-80 cm (preschool children) and 150 cm (adults) were measured at ten indoor and eight outdoor sites in the Taipei metropolitan area from March 2015 to February 2017. Four PM2.5 and seven PM10 indoor measurements exceeded the indoor air quality standard of Taiwan, whereas only two PM2.5 outdoor measurements exceeded the ambient air quality standard. The outdoor PM concentrations were related to traffic emissions, whereas the indoor PM concentrations were associated with ventilation rate and occupant density. The chronic daily PM1, PM2.5, and PM10 intakes of preschool children were notably higher than those of adults. In addition, the hazard quotient resulting from PM2.5 exposure indicated a significant health risk for preschool children (93.74% greater than 1). Consequently, reducing the exposure of preschool children to PM2.5 is an emerging issue in the Taipei metropolitan area.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Enfermedades Ambientales/epidemiología , Material Particulado/análisis , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire Interior/análisis , Cuidadores/estadística & datos numéricos , Cuidado del Niño/estadística & datos numéricos , Preescolar , Exposición a Riesgos Ambientales/estadística & datos numéricos , Enfermedades Ambientales/etiología , Monitoreo del Ambiente/métodos , Humanos , Exposición por Inhalación/análisis , Exposición por Inhalación/estadística & datos numéricos , Parques Recreativos/estadística & datos numéricos , Tamaño de la Partícula , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/etiología , Factores de Riesgo , Taiwán/epidemiología
11.
Behav Res Methods ; 50(1): 427-449, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28425059

RESUMEN

We report a new multidimensional measure of visual complexity (GraphCom) that captures variability in the complexity of graphs within and across writing systems. We applied the measure to 131 written languages, allowing comparisons of complexity and providing a basis for empirical testing of GraphCom. The measure includes four dimensions whose value in capturing the different visual properties of graphs had been demonstrated in prior reading research-(1) perimetric complexity, sensitive to the ratio of a written form to its surrounding white space (Pelli, Burns, Farell, & Moore-Page, 2006); (2) number of disconnected components, sensitive to discontinuity (Gibson, 1969); (3) number of connected points, sensitive to continuity (Lanthier, Risko, Stolz, & Besner, 2009); and (4) number of simple features, sensitive to the strokes that compose graphs (Wu, Zhou, & Shu, 1999). In our analysis of the complexity of 21,550 graphs, we (a) determined the complexity variation across writing systems along each dimension, (b) examined the relationships among complexity patterns within and across writing systems, and (c) compared the dimensions in their abilities to differentiate the graphs from different writing systems, in order to predict human perceptual judgments (n = 180) of graphs with varying complexity. The results from the computational and experimental comparisons showed that GraphCom provides a measure of graphic complexity that exceeds previous measures in its empirical validation. The measure can be universally applied across writing systems, providing a research tool for studies of reading and writing.


Asunto(s)
Gráficos por Computador , Procesamiento de Lenguaje Natural , Humanos , Lenguaje , Lectura , Escritura
12.
Anal Chem ; 88(21): 10404-10410, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27686335

RESUMEN

Magnetic microbeads exhibit rapid separation characteristics and are widely employed for biomolecule and cell isolations in research laboratories, clinical diagnostics assays, and cell therapy manufacturing. However, micrometer particle diameters compromise biomarker recognition, which leads to long incubation times and significant reagent demands. Here, a stimuli-responsive binary reagent system is presented that combines the nanoscale benefits of efficient biomarker recognition and the microscale benefits of rapid magnetic separation. This system comprises magnetic nanoparticles and polymer-antibody (Ab) conjugates that transition from hydrophilic nanoscale reagents to microscale aggregates in response to temperature stimuli. The binary reagent system was benchmarked against Ab-labeled Dynabeads in terms of biomarker isolation kinetics, assay speed, and reagent needs. Surface plasmon resonance (SPR) measurements showed that polymer conjugation did not significantly alter the Ab's binding affinity or kinetics. ELISA analysis showed that the unconjugated Ab, polymer-Ab conjugates, and Ab-labeled Dynabeads exhibited similar equilibrium dissociation constants (Kd), ∼2 nM. However, the binary reagent system isolated HIV p24 antigen from spiked serum specimens (150 pg/mL) much more quickly than Dynabeads, which resulted in shorter binding times by tens of minutes, or about 30-50% shorter overall assay times. The binary reagent system showed improved performance because the Ab molecules were not conjugated to large, solid microparticle surfaces. This stimuli-responsive binary reagent system illustrates the potential advantages of nanoscale reagents in molecule and cell isolations for both research and clinical applications.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Proteína p24 del Núcleo del VIH/sangre , Inmunoconjugados/química , Nanopartículas de Magnetita/química , Polímeros/química , Resonancia por Plasmón de Superficie/métodos , Biomarcadores/sangre , VIH/aislamiento & purificación , Proteína p24 del Núcleo del VIH/análisis , Infecciones por VIH/sangre , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Indicadores y Reactivos , Multimerización de Proteína , Temperatura
13.
J Aerosol Sci ; 101: 133-143, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32287369

RESUMEN

Liquid impingers are utilized to collect bioaerosols for many advantages, such as avoiding dehydration of biological agents. However, many previous studies have reported that the liquid impingers are surprisingly inefficient for the collection of ultrafine bioaerosols, with collection efficiencies <30%. In the present work, we have successfully improved the collection efficiency of the liquid impinger (AGI30) to as high as 99% for particles in the size range of 20-400 nm with the aid of packed glass beads. We also systematically investigated the effects of influential factors on the collection efficiency. These factors include the volume of the sampling liquid (0, 20 and 30 mL), depth (0, 7 and 10 cm) of packed glass beads and sampling flow rate (4, 6 and 8 liter per min, lpm). According to our experimental results, increasing the depth of packed glass beads and the volume of sampling liquid can enhance the collection efficiency. Also, decreasing the sampling flow rate can increase the collection efficiency and reduce the loss of sampling liquid. For the sampling of viable MS2 phages, the collection efficiency of AGI30 sampler with packed glass beads is much higher than that without packed glass beads. Conclusively, this study validates that the granular bed filtration can enhance the collection efficiency of liquid impingers for submicron and ultrafine particles and viral aerosols.

14.
Photochem Photobiol Sci ; 13(9): 1305-10, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25007943

RESUMEN

Fungal spores are known as critical indoor allergens, and indoor air purification techniques including photocatalytic disinfection using titanium dioxide (TiO2), ultraviolet germicidal irradiation (UVGI) and ozonation, have been considerably investigated. However, most of the research is in regard to photocatalytic disinfection, focused on the anti-bacterial efficacy of TiO2 nanoparticles (NPs). Furthermore, some research even showed that the photocatalytic antifungal efficacy of TiO2 NPs may not be that significant. Thus, investigating the reasons behind the non-significant antifungal efficacy of TiO2 photocatalytic disinfection and enhancing the antifungal efficacy is indispensable. In this study, ozone was employed to improve the photocatalytic antifungal efficacy of the TiO2 NPs and nano-metal supported on TiO2 NPs. The commercial TiO2 NPs (Degussa (Evonik) P25) served as a good support, and incipient wetness impregnation was successfully exploited to prepare oxidized nano-metals (Ag, Cu and Ni) in this study. There were two surfaces (quartz and putty) used in the inactivation experiments of Aspergillus niger spores which were manipulated under two conditions: exposed to ultraviolet (UVC) light , and exposed to UVC and ozone simultaneously. The SEM images demonstrated that the spores were sheltered from UVC light in the microcracks between TiO2 agglomerates. When irradiating with UVC, the A. niger spores on the two testing surfaces, without TiO2 NPs, were inactivated faster than those with TiO2 NPs, implying a "sun block" effect of this material and a lower photocatalytic antifungal efficacy than UVGI. On both surfaces, the inactivation rate constants (k) of A. niger spores exposed to UVC and ozone simultaneously (on quartz: k = 2.09-6.94 h(-1), on putty: k = 3.17-6.66 h(-1)) were better than those exposed to only UVC (on quartz: k = 1.80-5.89 h(-1); on putty: k = 2.97-3.98 h(-1)), indicating ozone can enhance the UVGI antifungal efficacy.


Asunto(s)
Nanopartículas del Metal/química , Ozono/química , Protectores Solares/química , Titanio/química , Rayos Ultravioleta , Antifúngicos/química , Antifúngicos/farmacología , Aspergillus niger/fisiología , Catálisis , Nanopartículas del Metal/toxicidad , Ozono/farmacología , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/efectos de la radiación
15.
Bioeng Transl Med ; 9(2): e10633, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38435819

RESUMEN

A multifunctional bioreactor was fabricated in this study to investigate the facilitation efficiency of electrical and mechanical stimulations on myogenic differentiation. This bioreactor consisted of a highly stretchable conductive membrane prepared by depositing polypyrrole (PPy) on a flexible polydimethylsiloxane (PDMS) film. The tensile deformation of the PPy/PDMS membrane can be tuned by adjusting the channel depth. In addition, PPy/PDMS maintained its electrical conductivity under continuous cyclic stretching in the strain range of 6.5%-13% for 24 h. This device can be used to individually or simultaneously perform cyclic stretching and electrical stimulation. The results of single stimulation showed that either cyclic stretching or electrical stimulation upregulated myogenic gene expression and promoted myotube formation, where electrical stimulation improved better than cyclic stretching. However, only cyclic stretching can align C2C12 cells perpendicular to the stretching direction, and electrical stimulation did not affect cell morphology. Myosin heavy chain (MHC) immunostaining demonstrated that oriented cells under cyclic stretching resulted in parallel myotubes. The combination of these two stimuli exhibited synergetic effects on both myogenic gene regulation and myotube formation, and the incorporated electrical field did not affect the orientation effect of the cyclic stretching. These results suggested that these two treatments likely influenced cells through different pathways. Overall, the simultaneous application of cyclic stretching and electrical stimulation preserved both stimuli's advantages, so myo-differentiation can be highly improved to obtain abundant parallel myotubes, suggesting that our developed multifunctional bioreactor should benefit muscle tissue engineering applications.

16.
Inf inference ; 12(1): 210-311, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36761435

RESUMEN

This paper studies the linear convergence of the subspace constrained mean shift (SCMS) algorithm, a well-known algorithm for identifying a density ridge defined by a kernel density estimator. By arguing that the SCMS algorithm is a special variant of a subspace constrained gradient ascent (SCGA) algorithm with an adaptive step size, we derive the linear convergence of such SCGA algorithm. While the existing research focuses mainly on density ridges in the Euclidean space, we generalize density ridges and the SCMS algorithm to directional data. In particular, we establish the stability theorem of density ridges with directional data and prove the linear convergence of our proposed directional SCMS algorithm.

17.
Ann Oper Res ; : 1-32, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37361069

RESUMEN

A globally aging population results in the long-term care of people with chronic illnesses, affecting the living quality of the elderly. Integrating smart technology and long-term care services will enhance and maximize healthcare quality, while planning a smart long-term care information strategy could satisfy the variety of care demands regarding hospitals, home-care institutions, and communities. The evaluation of a smart long-term care information strategy is necessary to develop smart long-term care technology. This study applies a hybrid Multi-Criteria Decision-Making (MCDM) method, which uses the Decision-Making Trial and Evaluation Laboratory (DEMATEL) integrated with the Analytic Network Process (ANP) for ranking and priority of a smart long-term care information strategy. In addition, this study considers the various resource constraints (budget, network platform cost, training time, labor cost-saving ratio, and information transmission efficiency) into the Zero-one Goal Programming (ZOGP) model to capture the optimal smart long-term care information strategy portfolios. The results of this study indicate that a hybrid MCDM decision model can provide decision-makers with the optimal service platform selection for a smart long-term care information strategy that can maximize information service benefits and allocate constrained resources most efficiently.

18.
J Alzheimers Dis ; 92(1): 109-128, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36710669

RESUMEN

BACKGROUND: Lesbian and gay older adults have health disparities that are risk factors for Alzheimer's disease, yet little is known about the neurocognitive aging of sexual minority groups. OBJECTIVE: To explore cross-sectional and longitudinal dementia outcomes for adults in same-sex relationships (SSR) and those in mixed-sex relationships (MSR). METHODS: This prospective observational study utilized data from the National Alzheimer's Coordinating Center Uniform Data Set (NACC UDS) collected from contributing Alzheimer's Disease Research Centers. Participants were adults aged 55+ years at baseline with at least two visits in NACC UDS (from September 2005 to March 2021) who had a spouse, partner, or companion as a co-participant. Outcome measures included CDR® Dementia Staging Instrument, NACC UDS neuropsychological testing, and the Functional Activities Questionnaire. Multivariable linear mixed-effects models accounted for center clustering and repeated measures by individual. RESULTS: Both MSR and SSR groups experienced cognitive decline regardless of baseline diagnosis. In general, MSR and SSR groups did not differ statistically on cross-sectional or longitudinal estimates of functioning, dementia severity, or neuropsychological testing, with two primary exceptions. People in SSR with mild cognitive impairment showed less functional impairment at baseline (FAQ M = 2.61, SD = 3.18 vs. M = 3.97, SD = 4.53, respectively; p < 0.01). The SSR group with dementia had less steep decline in attention/working memory (ß estimates = -0.10 versus -0.18; p < 0.01). CONCLUSION: Participants in SSR did not show cognitive health disparities consistent with a minority stress model. Additional research into protective factors is warranted.


Asunto(s)
Enfermedad de Alzheimer , Envejecimiento Cognitivo , Disfunción Cognitiva , Femenino , Humanos , Anciano , Enfermedad de Alzheimer/psicología , Estudios Transversales , Disfunción Cognitiva/psicología , Pruebas Neuropsicológicas
19.
Mon Not R Astron Soc ; 517(1): 1197-1217, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36246727

RESUMEN

The latticework structure known as the cosmic web provides a valuable insight into the assembly history of large-scale structures. Despite the variety of methods to identify the cosmic web structures, they mostly rely on the assumption that galaxies are embedded in a Euclidean geometric space. Here, we present a novel cosmic web identifier called sconce (Spherical and CONic Cosmic wEb finder) that inherently considers the 2D (RA, DEC) spherical or the 3D (RA, DEC, z) conic geometry. The proposed algorithms in sconce generalize the well-known subspace constrained mean shift (scms) method and primarily address the predominant filament detection problem. They are intrinsic to the spherical/conic geometry and invariant to data rotations. We further test the efficacy of our method with an artificial cross-shaped filament example and apply it to the SDSS galaxy catalogue, revealing that the 2D spherical version of our algorithms is robust even in regions of high declination. Finally, using N-body simulations from Illustris, we show that the 3D conic version of our algorithms is more robust in detecting filaments than the standard scms method under the redshift distortions caused by the peculiar velocities of haloes. Our cosmic web finder is packaged in python as sconce-scms and has been made publicly available.

20.
Chemosphere ; 307(Pt 3): 135841, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35970218

RESUMEN

Triclosan (TCS) is commonly used as a biocide against bacterial and fungal infections. The overuse of TCS has resulted in its abundance in the natural environment. Sulfate radicals have been used for in-situ groundwater remediation because of their superior performance. In this study, Co-Fe/Al oxidation electrodes were prepared to investigate the effect of electrode configurations on TCS remediation using electrokinetic geooxidation (ECGO) technology coupled with peroxymonosulfate (PMS) in a soil system. The Co-Fe/Al electrodes catalyzed the activity of PMS by solid-phase Co2+ to produce sulfate radicals. Four electrode configurations, named G1-G4, applying a potential gradient of 2 V/cm, were conducted for ten days in all experiments. Results showed that 14.2-66.2% of TCS remediation efficiency was observed. TCS was mainly degraded by the Co-Fe/Al electrode and sulfate radicals rather than being removed by the electroosmotic flow. The degradation efficiencies of the G4 system (66.0%) and the G2 or G3 system (36.6% or 64.4%, respectively) were much higher than that of the G1 system. (13.5%). Three regions (effective, ineffective, and enhanced) were classified to explore the effect of the electric field on TCS remediation. The arrangement of the honeycomb cells was related to the area of enhanced region in the system, in which the superior remediation performance of the TCS was found. Therefore, TCS remediation performance is highly related to the electrode configuration and honeycomb arrangement in the system. The seven-unit honeycomb system (G4) demonstrated a linear and centralized arrangement, resulting in fast migration and excellent degradation of the TCS.


Asunto(s)
Desinfectantes , Restauración y Remediación Ambiental , Contaminantes del Suelo , Triclosán , Desinfectantes/análisis , Electrodos , Peróxidos , Suelo , Contaminantes del Suelo/análisis , Sulfatos/análisis , Triclosán/análisis
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