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1.
Adv Ophthalmol Pract Res ; 4(3): 164-172, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39114269

RESUMEN

Background: Uncorrected refractive error is a major cause of vision impairment worldwide and its increasing prevalent necessitates effective screening and management strategies. Meanwhile, deep learning, a subset of Artificial Intelligence, has significantly advanced ophthalmological diagnostics by automating tasks that required extensive clinical expertise. Although recent studies have investigated the use of deep learning models for refractive power detection through various imaging techniques, a comprehensive systematic review on this topic is has yet be done. This review aims to summarise and evaluate the performance of ocular image-based deep learning models in predicting refractive errors. Main text: We search on three databases (PubMed, Scopus, Web of Science) up till June 2023, focusing on deep learning applications in detecting refractive error from ocular images. We included studies that had reported refractive error outcomes, regardless of publication years. We systematically extracted and evaluated the continuous outcomes (sphere, SE, cylinder) and categorical outcomes (myopia), ground truth measurements, ocular imaging modalities, deep learning models, and performance metrics, adhering to PRISMA guidelines. Nine studies were identified and categorised into three groups: retinal photo-based (n â€‹= â€‹5), OCT-based (n â€‹= â€‹1), and external ocular photo-based (n â€‹= â€‹3).For high myopia prediction, retinal photo-based models achieved AUC between 0.91 and 0.98, sensitivity levels between 85.10% and 97.80%, and specificity levels between 76.40% and 94.50%. For continuous prediction, retinal photo-based models reported MAE ranging from 0.31D to 2.19D, and R 2 between 0.05 and 0.96. The OCT-based model achieved an AUC of 0.79-0.81, sensitivity of 82.30% and 87.20% and specificity of 61.70%-68.90%. For external ocular photo-based models, the AUC ranged from 0.91 to 0.99, sensitivity of 81.13%-84.00% and specificity of 74.00%-86.42%, MAE ranges from 0.07D to 0.18D and accuracy ranges from 81.60% to 96.70%. The reported papers collectively showed promising performances, in particular the retinal photo-based and external eye photo -based DL models. Conclusions: The integration of deep learning model and ocular imaging for refractive error detection appear promising. However, their real-world clinical utility in current screening workflow have yet been evaluated and would require thoughtful consideration in design and implementation.

2.
Molecules ; 29(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38675582

RESUMEN

Piper betle leaf powder is increasingly utilised as a health supplement. In this study, P. betle leaves were subjected to four different drying methods: convective air-drying, oven-drying, sun-drying, and no drying, with fresh leaves as control. Their antioxidant properties were then evaluated using colourimetric assays and GC-MS. Results showed that the sun-dried leaves had the highest (p < 0.05) total antioxidant capacity (66.23 ± 0.10 mg AAE/g), total polyphenol content (133.93 ± 3.76 mg GAE/g), total flavonoid content (81.25 ± 3.26 mg CE/g) and DPPH radical scavenging activity (56.48 ± 0.11%), and the lowest alkaloid content (45.684 ± 0.265 mg/gm). GC-MS analysis revealed that major constituents of aqueous extracts of fresh and sun-dried P. betle leaves were hydrazine 1,2-dimethyl-; ethyl aminomethylformimidate; glycerin; propanoic acid, 2-hydroxy-, methyl ester, (+/-)-; and 1,2-Cyclopentanedione. In conclusion, sun-dried leaves exhibited overall better antioxidant properties, and their aqueous extracts contained biologically active phytoconstituents that have uses in various fields.


Asunto(s)
Antioxidantes , Desecación , Piper betle , Extractos Vegetales , Hojas de la Planta , Hojas de la Planta/química , Antioxidantes/química , Antioxidantes/farmacología , Piper betle/química , Extractos Vegetales/química , Desecación/métodos , Flavonoides/química , Flavonoides/análisis , Polifenoles/química , Polifenoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Alcaloides/química , Alcaloides/análisis
3.
Lancet Glob Health ; 12(2): e243-e256, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38245115

RESUMEN

BACKGROUND: Men who have sex with men (MSM) in the Asia-Pacific region have a disproportionately high burden of HIV infection compared with the general population. Although pre-exposure prophylaxis (PrEP) for HIV is highly effective at preventing new HIV infections, the cost-effectiveness of PrEP for MSM in different countries in the Asia-Pacific region with varying PrEP coverage and HIV testing frequencies remains unstudied. We aimed to analyse the economic and health benefits of long-acting injectable cabotegravir (CAB-LA) compared with oral PrEP in high-income countries and low-income and middle-income countries within the Asia-Pacific region. METHODS: We developed a decision-analytic Markov model to evaluate the population impact and cost-effectiveness of PrEP scale-up among MSM in Australia, Thailand, and China. We assumed a static cohort of 100 000 MSM aged 18 years or older who were at risk of HIV infection, with a monthly cycle length over a 40-year time period. We evaluated hypothetical scenarios with universal PrEP coverage of 80% among 100 000 suitable MSM in each country. We modelled oral PrEP and CAB-LA for MSM with diverse HIV testing frequency strategies. We adopted the health-care system's perspective with a 3% annual discount rate. We calculated the incremental cost-effectiveness ratio (ICER), measured as additional cost per quality-adjusted life-year (QALY) gained, to compare different strategies with the status quo in each country. All costs were reported in 2021 US$. We also performed one-way, two-way, and probabilistic sensitivity analyses to assess the robustness of our findings. FINDINGS: Compared with the status quo in each country, expanding oral PrEP to 80% of suitable MSM would avert 8·1% of new HIV infections in Australia, 14·5% in Thailand, and 26·4% in China in a 40-year period. Expanding oral PrEP use with 6-monthly HIV testing for both PrEP and non-PrEP users was cost-saving for Australia. Similarly, expanding oral PrEP use remained the most cost-effective strategy in both Thailand and China, but optimal testing frequency varied, with annual testing in Thailand (ICER $4707 per QALY gained) and 3-monthly testing in China (ICER $16 926 per QALY gained) for both PrEP and non-PrEP users. We also found that replacing oral PrEP with CAB-LA for MSM could avert more new HIV infections (12·8% in Australia, 27·6% in Thailand, and 32·8% in China), but implementing CAB-LA was not cost-effective due to its high cost. The cost of CAB-LA would need to be reduced by 50-90% and be used as a complementary strategy to oral PrEP to be cost-effective in these countries. INTERPRETATION: Expanding oral PrEP use for MSM, with country-specific testing frequency, is cost-effective in Australia, Thailand, and China. Due to the high cost, CAB-LA is currently not affordable as a single-use strategy but might be offered as an additional option to oral PrEP. FUNDING: Ministry of Science and Technology of the People's Republic of China, the Australian National Health and Medical Research Council, National Key Research and Development Program of China, and National Natural Science Foundation of China.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Masculino , Humanos , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Homosexualidad Masculina , Fármacos Anti-VIH/uso terapéutico , Análisis de Costo-Efectividad , Tailandia , Análisis Costo-Beneficio , Australia/epidemiología , China/epidemiología
4.
Sci Rep ; 14(1): 2141, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273021

RESUMEN

We experimentally demonstrated the generation of domain-wall dark pulse in an Erbium-doped fiber laser using the combination of a 10 cm graded index multimode fiber sandwiched by single mode fibers as artificial saturable absorber. The interaction of phase difference in grade index multimode fiber allowed the stable dual-wavelength oscillation in the cavity. The dual-wavelength centered at 1567.2 nm and 1569.4 nm produces the topological defect in temporal domain and achieved a dark pulse formation with repetition rate of 21.5 MHz. The highest average pulse energy is calculated as 769.6 pJ with pulse width of 5 ns. Throughout the operating pump power range, the average pulse energy and output power increase linearly, with R2 of 0.9999 and achieved the laser efficiency of 9.33%. From the measurement in frequency domain, the signal-to-noise ratio is measured as 49 dB. As compared to reported DW dark pulse works, the proposed structure only required a short length of multimode fiber, which allowed the domain-wall dark pulse to achieve higher pulse repetition rate. The venture of domain wall dark pulse is potentially to pave the foundation toward sustainable industrial growth.

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1006523

RESUMEN

@#Objective     To evaluate the clinical effectiveness of valve-sparing aortic root replacement (VSARR) in the treatment of patients with dilated aortic root after operation for tetralogy of Fallot (TOF). Methods     A retrospective analysis was conducted on clinical data of TOF patients with aortic root dilation who underwent VSARR in our hospital from 2016 to 2022. Results     Finally 14 patients were collected, including 8 males and 6 females, with a median age of 22 years ranging from 12-48 years. Among them, 5 patients had severe aortic valve regurgitation, 4 moderate regurgitation, and 5 mild or no regurgitation. Six patients had sinus of valsalva dilation, and 8 significant dilation of the ascending aorta. One patient had residual shunt due to ventricular septal defect, and 9 severe pulmonary valve regurgitation. The David procedure was performed in 10 patients, Yacoub procedure in 2 patients, and Florida sleeve in 2 patients. There was no perioperative mortality in the group. The median follow-up time was 2.9 years (ranging from 0.4 to 6.0 years). One patient had mild aortic valve regurgitation, and the rest had minimal or no regurgitation. One patient had mild stenosis of the left ventricular outflow tract, and the rest patients had no obvious stenosis. Conclusion     VSARR is a satisfactory treatment for aortic root dilation in patients with TOF, with no significant increase in the incidence of left ventricular outflow tract stenosis or aortic regurgitation during mid-term follow-up.

6.
J Chem Phys ; 159(22)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38063219

RESUMEN

Interfacial water is ubiquitous on Earth, playing a crucial role in biology, chemistry, physics, materials science, and environmental science. Multiscale, hierarchical water motions on the surface of different materials under different conditions (temperature, hydration extent, pressure, etc.) and the coupling of this motion with the substrate/solute dynamics and the influence of these couplings on the material functions are complex, long lasting, interdisciplinary research topics. We herein focus on the coupling between the picosecond dynamical onset of substrates and their surface water at temperatures lower than the freezing point (273 K) and discuss the recent progress in the study of its molecular mechanisms.

7.
iScience ; 26(11): 108163, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37915603

RESUMEN

In light of growing interest in using emerging large language models (LLMs) for self-diagnosis, we systematically assessed the performance of ChatGPT-3.5, ChatGPT-4.0, and Google Bard in delivering proficient responses to 37 common inquiries regarding ocular symptoms. Responses were masked, randomly shuffled, and then graded by three consultant-level ophthalmologists for accuracy (poor, borderline, good) and comprehensiveness. Additionally, we evaluated the self-awareness capabilities (ability to self-check and self-correct) of the LLM-Chatbots. 89.2% of ChatGPT-4.0 responses were 'good'-rated, outperforming ChatGPT-3.5 (59.5%) and Google Bard (40.5%) significantly (all p < 0.001). All three LLM-Chatbots showed optimal mean comprehensiveness scores as well (ranging from 4.6 to 4.7 out of 5). However, they exhibited subpar to moderate self-awareness capabilities. Our study underscores the potential of ChatGPT-4.0 in delivering accurate and comprehensive responses to ocular symptom inquiries. Future rigorous validation of their performance is crucial to ensure their reliability and appropriateness for actual clinical use.

8.
J Phys Chem Lett ; 14(48): 10784-10793, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38011674

RESUMEN

The emerging Pb-free double perovskites (DPs) are acknowledged as the most potential nontoxic alternatives to lead halide perovskites for thin-film photovoltaics, yet their photophysical properties significantly lag behind expectations. To tackle this issue, it is imperative to conduct a systematic investigation of the structure and optoelectronic properties and to sift through vast chemical space to extract new types of Pb-free DPs with exceptional optoelectronic characteristics and thermal stability. Through high-throughput first-principal calculations, we demonstrate that apart from a select few Pb-free DPs (e.g., Cs2InSbCl6 and Cs2TlBiBr6), other categories, even with suitable direct electronic bandgaps, exhibit inferior optical absorption due to the inversion symmetry-induced parity-forbidden transitions. The mismatch between the electronic and optical bandgap, thence, casts doubt on the reliability of the electronic bandgap as a criterion for Pb-free DPs in various optoelectronics. The assessed limited thermostability under operational conditions, however, hinders any Pb-free DPs from effectively serving as photovoltaic absorbers. Alongside the compositional engineering discussed above, the prospect of manipulating local-site symmetry and disrupting the parity forbidden transitions in stabilized Pb-free DPs through materials engineering should be recognized as a pivotal and rational avenue toward achieving high performance.

9.
Nanomaterials (Basel) ; 13(9)2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37177083

RESUMEN

In this work, we present the generation of two distinct types of soliton pulses using a Bismuth Selenide (Bi2Se3) saturable absorber (SA) synthesized in our laboratory. The soliton pulses were generated in two different laser cavity configurations, resulting in two types of solitons: a soliton pulse with Kelly sidebands and a bunched soliton pulse with peak-dip sidebands. Both solitons operated at the fundamental repetition rate-23.3 MHz (for the soliton with Kelly sidebands) and 13 MHz (for the bunched soliton with peak-dip sidebands). We observed that the accumulation of nonlinear phase shift from the added single mode fiber (SMF) split the single soliton pulse into 44 pulses in a bunched oscillation envelope. At the same time, peak-dip sidebands were imposed on the bunched soliton spectrum due to constructive and destructive interferences between soliton pulse and dispersive waves. The measured pulse width for both solitons were 0.63 ps (for the soliton with Kelly sidebands) and 1.52 ps (for the bunched soliton with peak-dip sidebands), respectively. Our results demonstrate the potential of Bi2Se3 SAs in generating different types of soliton pulses, which could have potential applications in various areas of optical communication and spectroscopy.

10.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1024075

RESUMEN

Gegen Qinlian Decoction is a classical prescription with the function of relieving exterior and interior syndromes.The formula contains complex chemical components and is prepared into several dosage forms regulating the function of the gut.The review discusses the chemical components,common dosage forms,clinical application and effect on the intestinal barrier of Gegen Qinlian Decoction,so as to provide a basis for its further development and utilization.

11.
Micromachines (Basel) ; 13(12)2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36557488

RESUMEN

A non-contact ultrasonic abrasive machining approach provides a potential solution to overcome the challenges of machining efficiency in the high-precision polishing of optical components. Accurately modeling the material removal distribution (removal function (RF)) and surface morphology is very important in establishing this new computer-controlled deterministic polishing technique. However, it is a challenging task due to the absence of an in-depth understanding of the evolution mechanism of the material removal distribution and the knowledge of the evolution law of the microscopic surface morphology under the complex action of ultrasonic polishing while submerged in liquid. In this study, the formation of the RF and the surface morphology were modeled by investigating the cavitation density distribution and conducting experiments. The research results showed that the material removal caused by cavitation bubble explosions was uniformly distributed across the entire working surface and had a 0.25 mm edge influence range. The flow scour removal was mainly concentrated in the high-velocity flow zone around the machining area. The roughness of the machined surface increased linearly with an increase in the amplitude and gap. Increasing the particle concentration significantly improved the material removal rate, and the generated surface exhibited better removal uniformity and lower surface roughness.

12.
Soc Sci Med ; 314: 115403, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36244227

RESUMEN

While existing studies have reported and recognized country-of-origin effects on the intentions to vaccinate against COVID-19 among individual citizens in some countries, the causal mechanism behind such effects to inform public health policymakers remain unexplored. Adding up a quality cue explanation for such effects to the existing literature, the authors argue that individual consumers are less willing to get a vaccine designed and manufactured by a country with a significantly lower quality perception than other countries. A survey experiment that recruited a nationally representative sample of Taiwanese adults (n = 1951) between December 13, 2020 and January 11, 2021 was designed and conducted to test the argument. We find that all else equal, Taiwanese respondents were on average less likely to express stronger willingness to take a vaccine from China than from the US, Germany, and Taiwan. Furthermore, even when the intrinsic quality of the vaccine was held constant by the experimental design, respondents still had a significantly lower quality perception of the vaccine from China, both in terms of perceived protection and severe side effects. Further evidence from casual mediation analyses shows that about 33% and 11% of the total average causal effects of the "China" country-of-origin label on vaccine uptake intention were respectively mediated through the perceived efficacy of protection and perceived risk of experiencing severe side effects. We conclude that quality cue constitutes one of many casual mechanisms behind widely reported country-of-origin effects on intention to vaccinate against COVID-19.


Asunto(s)
COVID-19 , Vacunas , Adulto , Humanos , COVID-19/prevención & control , Intención , Señales (Psicología) , Taiwán/epidemiología , Vacunación
13.
PLoS One ; 17(10): e0274814, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36197921

RESUMEN

Mesenchymal stem cells (MSCs) have seen an elevated use in clinical works like regenerative medicine. Its potential therapeutic properties increases when used in tandem with complementary agents like bio-based materials. Therefore, the present study is the first to investigate the cytotoxicity of a highly valued medicinal plant, Moringa oleifera, on human Wharton's Jelly mesenchymal stem cells (hWJMSCs) and its effects on the cells' gene expression when used as a pre-treatment agent in vitro. M. oleifera leaves (MOL) were dried and subjected to UHPLC-QTOF/MS analysis, revealing several major compounds like apigenin, kaempferol, and quercetin in the MOL, with various biological activities like antioxidant and anti-cancer properties. We then treated the hWJMSCs with MOL and noticed a dose-dependant inhibition on the cells' proliferation. RNA-sequencing was performed to explain the possible mechanism of action and revealed genes like PPP1R1C, SULT2B1, CDKN1A, mir-154 and CCNB1, whose expression patterns were closely associated with the negative cell cycle regulation and cell cycle arrest process. This is also evident from gene set enrichment analysis where the GO and KEGG terms for down-regulated pathways were closely related to the cell cycle regulation. The Ingenuity pathway analysis (IPA) software further predicted the significant activation of (p < 0.05, z-score > 2) of the G2/M DNA damage checkpoint regulation pathway. The present study suggests that MOL exhibits an antiproliferative effect on hWJMSCs via cell cycle arrest and apoptotic pathways. We believe that this study provides an important baseline reference for future works involving MOL's potential to accompany MSCs for clinical works. Future works can take advantage of the cell's strong anti-cancer gene expression found in this study, and evaluate our MOL treatment on various cancer cell lines.


Asunto(s)
Células Madre Mesenquimatosas , MicroARNs , Moringa oleifera , Gelatina de Wharton , Antioxidantes/metabolismo , Apigenina/farmacología , Diferenciación Celular , Humanos , Quempferoles/metabolismo , Quempferoles/farmacología , MicroARNs/metabolismo , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Quercetina/farmacología , ARN/metabolismo
14.
Phys Chem Chem Phys ; 24(35): 21165-21177, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36039891

RESUMEN

Antifreeze glycoproteins (AFGPs) inhibit ice recrystallization by a mechanism remaining largely elusive. The dynamics of AFGPs' hydration water and its involvement in the antifreeze activity, for instance, have not been identified conclusively. We herein, by simulation and theory, examined the picosecond site-specific water dynamics in the first hydration layer of a solvated AFGP8. Using a hydrogen bond switch event-based treatment, we strictly excluded the non-first layer water contribution. The observed water dynamics is much more retarded and inhomogeneous compared to the result of other commonly adopted treatments with non-first layer water contributions included. A molecular jump model analysis, with the cross-correlation between hydrogen bond switch molecular frames included, further indicates that excluding the non-first layer water contribution enhances the slow component in water dynamics, which couples strongly with the local environment. Further comparison with the structured ubiquitin protein revealed that, although the overall relaxation time distributions are similar between two proteins, a significant portion (>30%) of water hydrogen bond switching processes on the AFGP8 surface are considerably slower since they are trapped between the disaccharides and other protein regions. AFGP8 therefore resembles much the situation of an enzyme binding cleft or a DNA groove, where considerable slowdown of hydration water dynamics is observed due to the confinement. When bound to the ice surface, these slow, disordered water molecules may become a factor hindering the ice growth.


Asunto(s)
Hielo , Agua , Proteínas Anticongelantes/química , Enlace de Hidrógeno , Modelos Moleculares , Simulación de Dinámica Molecular , Agua/química
15.
Saudi J Biol Sci ; 29(6): 103290, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35521359

RESUMEN

The recent COVID-19 pandemic resulted in major postharvest losses because most fresh produce could not be sold. Drying is an important thermal-based food preservation method which could have prolonged the shelf-life of these produce, but most drying technologies are costly, and cannot be afforded by small-time farmers. From this context, we were interested in evaluating the drying of Moringa oleifera leaves (MOL) using a low-cost self-built prototype convective-air dryer (CAD), alongside conventional drying methods for its antioxidant properties, microbial load and phytoconstituents. Results showed total polyphenol content was the highest (p < 0.05) in our CAD samples, and it retained among the highest total flavonoid content, total antioxidant capacity, total alkaloid content and DPPH radical scavenging activity. Furthermore, methanolic CAD extract presented lower coliform and yeast and mold count than the aqueous CAD extract. We also briefly explored MOL as a sanitizer where the microbial load of the methanolic extract was comparable (p > 0.05) with several commercial non-alcoholic sanitizers, indicating its commercialization potential as a bio-friendly sanitizer. Finally, using GC-MS, we are the first to report (best of our knowledge) on the presence of caprolactam, an important bio-medical field compound, in the CAD sample's aqueous extract.

16.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-980029

RESUMEN

@#Introduction: Preclinical studies on mesenchymal stromal cells (MSC) have allowed the cells to be considered as a promising candidate for cellular therapy. In recent years, conflicting data have been reported regarding various aspects of their characteristics, development and differentiation potential, which may be due to arrange of factors. Among the factors worth investigating is the culture medium formulation. Methods: Here we have made a comparative characterization of mouse bone marrow mesenchymal stromal cells (mBM-MSC) that were cultured using two common supplements, MesenCult™ Stimulatory Supplement (MSS) and fetal bovine serum (FBS), under the same experimental conditions at different passages. Clonogenic potential, cumulative population doubling level (CPDL), population doubling time (PDT), immunophenotyping, differentiation, immunosuppression potentials and chromosome analysis of early and late passages mBM-MSC were assessed. Results: Our findings showed that the CPDL, immunophenotype and immunosuppression potential of mBM-MSC were similar. However, variations were seen in their clonogenicity, population doubling time and differentiation efficacy whereby all of these were enhanced in DMSS. These observations suggest that their genetic make-up may be affected by both supplements upon prolonged culture. Interestingly, this conjecture was supported when chromosomal analysis revealed genetic instability of mBM-MSCs cultured in both supplements. Conclusion: In conclusion, culture medium formulation was shown to cause variations and spontaneous transformation in mBM-MSCs raising concerns on the usage of late passages mBMMSCs in fundamental and preclinical downstream experiments.

18.
J Formos Med Assoc ; 120 Suppl 1: S106-S117, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34119392

RESUMEN

BACKGROUND: Global burden of COVID-19 has not been well studied, disability-adjusted life years (DALYs) and value of statistical life (VSL) metrics were therefore proposed to quantify its impacts on health and economic loss globally. METHODS: The life expectancy, cases, and death numbers of COVID-19 until 30th April 2021 were retrieved from open data to derive the epidemiological profiles and DALYs (including years of life lost (YLL) and years loss due to disability (YLD)) by four periods. The VSL estimates were estimated by using hedonic wage method (HWM) and contingent valuation method (CVM). The estimate of willingness to pay using CVM was based on the meta-regression mixed model. Machine learning method was used for classification. RESULTS: Globally, DALYs (in thousands) due to COVID-19 was tallied as 31,930 from Period I to IV. YLL dominated over YLD. The estimates of VSL were US$591 billion and US$5135 billion based on HWM and CVM, respectively. The estimate of VSL increased from US$579 billion in Period I to US$2160 billion in Period IV using CVM. The higher the human development index (HDI), the higher the value of DALYs and VSL. However, there exits the disparity even at the same level of HDI. Machine learning analysis categorized eight patterns of global burden of COVID-19 with a large variation from US$0.001 billion to US$691.4 billion. CONCLUSION: Global burden of COVID-19 pandemic resulted in substantial health and value of life loss particularly in developed economies. Classifications of such health and economic loss is informative to early preparation of adequate resource to reduce impacts.


Asunto(s)
COVID-19 , Salud Global , Pandemias , COVID-19/epidemiología , Humanos , Años de Vida Ajustados por Calidad de Vida , SARS-CoV-2 , Valor de la Vida
19.
J Formos Med Assoc ; 120 Suppl 1: S95-S105, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34108119

RESUMEN

BACKGROUND: Vaccine is supposed to be the most effective means to prevent COVID-19 as it may not only save lives but also reduce productivity loss due to resuming pre-pandemic activities. Providing the results of economic evaluation for mass vaccination is of paramount importance for all stakeholders worldwide. METHODS: We developed a Markov decision tree for the economic evaluation of mass vaccination against COVID-19. The effectiveness of reducing outcomes after the administration of three COVID-19 vaccines (BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), and AZD1222 (Oxford-AstraZeneca)) were modelled with empirical parameters obtained from literatures. The direct cost of vaccine and COVID-19 related medical cost, the indirect cost of productivity loss due to vaccine jabs and hospitalization, and the productivity loss were accumulated given different vaccination scenarios. We reported the incremental cost-utility ratio and benefit/cost (B/C) ratio of three vaccines compared to no vaccination with a probabilistic approach. RESULTS: Moderna and Pfizer vaccines won the greatest effectiveness among the three vaccines under consideration. After taking both direct and indirect costs into account, all of the three vaccines dominated no vaccination strategy. The results of B/C ratio show that one dollar invested in vaccine would have USD $13, USD $23, and USD $28 in return for Moderna, Pfizer, and AstraZeneca, respectively when health and education loss are considered. The corresponding figures taking value of the statistical life into account were USD $176, USD $300, and USD $443. CONCLUSION: Mass vaccination against COVID-19 with three current available vaccines is cost-saving for gaining more lives and less cost incurred.


Asunto(s)
COVID-19 , Vacunación Masiva , Vacuna BNT162 , COVID-19/economía , COVID-19/prevención & control , Vacunas contra la COVID-19/economía , ChAdOx1 nCoV-19 , Análisis Costo-Beneficio , Humanos , Vacunación Masiva/economía
20.
Polymers (Basel) ; 13(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671304

RESUMEN

Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system. Zinc chloride (ZnCl2) with various contents (2 to 8 wt%) was used to surface modify the CWF and the effects of ZnCl2 composition on the surface morphology and chemistry of the CWF filler were investigated. Furthermore, the absorptive, mechanical, thermal, and electrical properties of the EVA composites containing CWF-ZnCl2 were also analyzed. SEM images indicated changes in the morphology of the CWF while FTIR analysis proved the presence of ZnCl2 functional groups in the CWF. EVA composites incorporating the CWF-ZnCl2 showed superior mechanical, thermal and electrical properties compared to the ones containing the CWF. The optimum content of ZnCl2 was found to be 6 wt%. Surface modification raised the electrical conductivity of the EVA/CWF composite through the development of conductive deposits in the porous structure of the CWF as a channel for ionic and electronic transfer between the CWF and EVA matrix.

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