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1.
Cureus ; 15(7): e41704, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37575722

RESUMO

INTRODUCTION: The increasing use of minimally invasive orthopedic procedures has led to a greater reliance on fluoroscopy, resulting in elevated radiation exposure for surgeons. This study aimed to evaluate the knowledge, awareness, and daily practices of orthopedic surgeons regarding radiation safety in an academic hospital. Understanding radiation safety is crucial to minimize patient exposure and prevent adverse effects on surgeons. METHODS: This cross-sectional study was conducted at the Department of Orthopedics of different tertiary care hospitals in Rawalpindi, Pakistan. Data were collected prospectively for two years, and a total of 505 participants, including residents, consultants, and operation theatre assistants, completed a questionnaire. The questionnaire was validated by experts and covered information on fluoroscopy usage, frequency of surgeries, awareness of radiation safety, and protective measures. Ethical approval was obtained, and data were analyzed using SPSS version 26.0. RESULTS: The majority of participants were male (74.1%), and the sample included various ranks of orthopedic surgeons. Only 56.2% of participants were aware of the usage of fluoroscopy, and 40.2% had read some research on the topic. While 44.6% used lead aprons for radiation protection, the usage of other protective measures and dosimeters was limited. The mediation analysis showed an insignificant indirect association between the rank of orthopedic surgeons, number of surgeries performed, and fluoroscopy usage as a mediator. Awareness and reading research on fluoroscopy were significantly associated with radiation protection. CONCLUSION: The knowledge, awareness, and daily practices of orthopedic surgeons regarding radiation safety in fluoroscopy use need improvement. The findings emphasize the importance of implementing training programs, providing radiation protection devices, and ensuring compliance with safety guidelines.

3.
Philos Trans A Math Phys Eng Sci ; 381(2241): 20210414, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36463920

RESUMO

Novel magnetic materials are important for future technological advances. Theoretical and numerical calculations of ground-state properties are essential in understanding these materials, however, computational complexity limits conventional methods for studying these states. Here we investigate an alternative approach to preparing materials ground states using the quantum approximate optimization algorithm (QAOA) on near-term quantum computers. We study classical Ising spin models on unit cells of square, Shastry-Sutherland and triangular lattices, with varying field amplitudes and couplings in the material Hamiltonian. We find relationships between the theoretical QAOA success probability and the structure of the ground state, indicating that only a modest number of measurements ([Formula: see text]) are needed to find the ground state of our nine-spin Hamiltonians, even for parameters leading to frustrated magnetism. We further demonstrate the approach in calculations on a trapped-ion quantum computer and succeed in recovering each ground state of the Shastry-Sutherland unit cell with probabilities close to ideal theoretical values. The results demonstrate the viability of QAOA for materials ground state preparation in the frustrated Ising limit, giving important first steps towards larger sizes and more complex Hamiltonians where quantum computational advantage may prove essential in developing a systematic understanding of novel materials. This article is part of the theme issue 'Quantum annealing and computation: challenges and perspectives'.

4.
PLoS One ; 17(4): e0262037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413049

RESUMO

The purpose of this research was to investigate the key factors that influence behavioral intention to adopt MOOCs. The study was conducted in three countries namely, Poland, Thailand, and Pakistan. The study was considered significant considering the advancements in technology that have had an unprecedented impact on education, and the need to conduct learning online due to the COVID-19 to pandemics. The research adopted the Unified Theory of Acceptance and Use of Technology (UTAUT2) and extended it by including other variables including culture, social distancing, and absorptive capacity. The study was conducted using the quantitative methodology, where the data was collected using a structured questionnaire. The data was collected from a sample from each of the three countries, and sample sizes were 455, 490, and 513 for Poland, Thailand, and Pakistan respectively. The data were analyzed using Structural Equation Modeling (SEM) and multi-group SEM analysis. The results of the study indicated that effort expectancy and culture significantly and positively influenced behavioral intention to use MOOCs in all three countries. As well, absorptive capacity is mediated significantly by performance expectancy and effort expectancy. Facilitating conditions have a significant influence on MOOCs in both Thailand and Pakistan. Social influence has a significant influence on behavioral intention to use MOOCs in Thailand, hedonic motivation and price value have a significant influence on behavioral intention to use MOOCs in Poland, and the habit has a significant factor in Pakistan. The keys aspects influencing behavioral intention to Use MOOCs were different in Poland, Thailand, and Pakistan, in various factors which are performance expectancy, social distancing, price value, facilitating conditions, and social influence. The research recommended that it is important to evaluate the situation and prevailing conditions of the concerned country, before implementing the MOOCs and the associated online learning practices.


Assuntos
COVID-19 , Intenção , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Motivação , Inquéritos e Questionários , Tecnologia
5.
J Mater Chem B ; 9(33): 6623-6633, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34378616

RESUMO

Cancer treatment has been recently energized by nanomaterials that simultaneously offer diagnostic and therapeutic effects. Among the imaging and treatment modalities in frontline research today, magnetic resonance imaging (MRI) and phototherapy have gained significant interest due to their noninvasiveness among other intriguing benefits. Herein, Fe(iii) was adsorbed on titanium dioxide to develop magnetic Fe-TiO2 nanocomposites (NCs) which leverage the Fe moiety in a double-edge-sword approach to: (i) achieve T1-weighted MRI contrast enhancement, and (ii) improve the well-established photodynamic therapeutic efficacy of TiO2 nanoparticles. Interestingly, the proposed NCs exhibit classic T1 MRI contrast agent properties (r1 = 1.16 mM-1 s-1) that are comparable to those of clinically available contrast agents. Moreover, the NCs induce negligible cytotoxicity in traditional methods and show remarkable support to the proliferation of intestine organoids, an advanced toxicity evaluation system based on three-dimensional organoids, which could benefit their potential safe application for in vivo cancer theranostics. Aided by the Fenton reaction contribution of the Fe component of the Fe-TiO2 NCs, considerable photo-killing of cancer cells is achieved upon UV irradiation at very low (2.5 mW cm-2) intensity in typical cancer PDT. It is therefore expected that this study will guide the engineering of other biocompatible magnetic titania-based nanosystems with multi-faceted properties for biomedical applications.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Imageamento por Ressonância Magnética , Fármacos Fotossensibilizantes/farmacologia , Fototerapia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Fenômenos Magnéticos , Nanopartículas de Magnetita/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Nanotubos/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Titânio/química , Titânio/farmacologia , Raios Ultravioleta
7.
Am J Ther ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33181529
10.
Nano Lett ; 17(2): 1140-1148, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28027642

RESUMO

Particulate matter (PM) pollution has caused many serious public health issues. Whereas indoor air protection usually relies on expensive and energy-consuming filtering devices, direct PM filtration by window screens has attracted increasing attention. Recently, electrospun polymer nanofiber networks have been developed as transparent filters for highly efficient PM2.5 removal; however, it remains challenging to uniformly coat the nanofibers on window screens on a large scale and with low cost. Here, we report a blow-spinning technique that is fast, efficient, and free of high voltages for the large-scale direct coating of nanofibers onto window screens for indoor PM pollution protection. We have achieved a transparent air filter of 80% optical transparency with >99% standard removal efficiency level for PM2.5. A test on a real window (1 m × 2 m) in Beijing has proven that the nanofiber transparent air filter acquires excellent PM2.5 removal efficiency of 90.6% over 12 h under extremely hazy air conditions (PM2.5 mass concentration > 708 µg/m3). Moreover, we show that the nanofibers can be readily coated on the window screen for pollution protection and can be easily removed by wiping the screen after hazardous days.

11.
Nano Lett ; 16(1): 583-7, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26654117

RESUMO

Magnetization and electric-field coupling is fundamentally interesting and important. Specifically, current- or voltage-driven magnetization switching at room temperature is highly desirable from scientific and technological viewpoints. Herein, we demonstrate that magnetization can be controlled via the discharge-charge cycling of a lithium-ion battery (LIB) with rationally designed electrode nanomaterials. Reversible manipulation of magnetism over 3 orders of magnitude was achieved by controlling the lithiation/delithiation of a nanoscale α-Fe2O3-based electrode. The process was completed rapidly under room-temperature conditions. Our results indicate that in addition to energy storage LIBs, which have been under continuous development for several decades, provide exciting opportunities for the multireversible magnetization of magnetic fields.

12.
Small ; 11(45): 6009-12, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26449629

RESUMO

Silicon-based nanoparticles with unique "nanodandelion" structures are synthesized by a simple and efficient laser ablation method. Such material can be used as a stable anode for Li-ion batteries with a high capacity of ≈1500 mAh g(-1) and for more than 800 electrochemical cycles without obvious capacity decay.

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