83 research outputs found

    Mechanically stable solution-processed transparent conductive electrodes for optoelectronic applications

    Get PDF
    The bilayer structure of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) coating on silver nanowires (AgNWs) film is a promising structure for replacing indium tin oxide (ITO) as a flexible transparent conductive electrode. Pristine PEDOT:PSS film due to its hydrophilicity and high permeability cannot fully protect AgNWs from mechanical stress and oxidation. Here, we present a composite approach that improves mechanical properties and lifespan of the AgNWs/PEDOT:PSS electrode by adding polyvinyl alcohol (PVA) as a polymer-surfactant. It is shown that addition of PVA improves the conductivity as well as the stability of hybrid electrode under demanding mechanical stress conditions. The drop in conductivity of the hybrid electrode is only 17% after 2000 repeated bending cycles whereas the reference electrode has shown a dramatic drop of 180% in the conductivity. We speculate that generation of hydrogen bonds between PEDOT:PSS and PVA increases adhesivity and cohesivity of the conductive polymer film to the sublayer. So PEDOT:PSS-PVA film not only fixes the arrangement of AgNWs but also improves the welding on cross junction points. By addition of PVA, optoelectronic performance (Figure-of-merit (ΦTC)) of the electrode is improved from ΦTC = 2.646 × 10-3 Ω-1 for AgNWs/PEDOT:PSS to ΦTC = 3.819 × 10-3 Ω-1 for AgNWs/PEDOT:PSS-PVA electrode and power conversion efficiency (PCE) of the polymer solar cell (PSC) is increased by over 17%.</p

    Cutting tool tracking and recognition based on infrared and visual imaging systems using principal component analysis (PCA) and discrete wavelet transform (DWT) combined with neural networks

    Get PDF
    The implementation of computerised condition monitoring systems for the detection cutting tools’ correct installation and fault diagnosis is of a high importance in modern manufacturing industries. The primary function of a condition monitoring system is to check the existence of the tool before starting any machining process and ensure its health during operation. The aim of this study is to assess the detection of the existence of the tool in the spindle and its health (i.e. normal or broken) using infrared and vision systems as a non-contact methodology. The application of Principal Component Analysis (PCA) and Discrete Wavelet Transform (DWT) combined with neural networks are investigated using both types of data in order to establish an effective and reliable novel software program for tool tracking and health recognition. Infrared and visual cameras are used to locate and track the cutting tool during the machining process using a suitable analysis and image processing algorithms. The capabilities of PCA and Discrete Wavelet Transform (DWT) combined with neural networks are investigated in recognising the tool’s condition by comparing the characteristics of the tool to those of known conditions in the training set. The experimental results have shown high performance when using the infrared data in comparison to visual images for the selected image and signal processing algorithms

    Evaluation of Fis-1 and miR-484 Expression Levels in Tumor Tissue Samples and Healthy Tumor Margins in Lung Cancer

    Get PDF
    Background: MicroRNAs (miRNAs) regulate gene expression and various cellular activities. They also hold significant importance in the progression and development of human malignancies. Among these, miRNA-484 and the Fis-1 gene have been identified as having substantial roles in lung cancer. This study aims to ascertain miRNA-484 and Fis-1 gene expression levels in non-small cell lung cancer (NSCLC) patients.Method: In this case-control study, 45 pairs of tumor tissues and their corresponding healthy margin tissues were surgically obtained from NSCLC patients and promptly preserved in liquid nitrogen after excision. Total RNA extraction was performed using TRIzol, followed by cDNA synthesis using a designated kit. Afterward, we used quantitative reverse transcription polymerase chain reaction (qRT-PCR) to measure the expression levels of miRNA-484 and the Fis-1 gene. Furthermore, the clinicopathological characteristics of the NSCLC patients were assessed.Results: Our findings revealed an upregulation of miRNA-484 expression and downregulation of Fis-1 gene expression in NSCLC tissues compared with non-tumor tissues. Additionally, significant correlations were observed between miRNA-484 and Fis-1 gene expression levels and clinicopathological features of the patients, including factors such as lymph node involvement and distant metastasis.Conclusion: These findings suggest the potential utility of Fis-1 and miR-484 as prognostic and diagnostic markers in NSCLC

    Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

    Get PDF
    Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations

    Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

    Get PDF
    A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5) million) in 2000 to 6.0% (55.5 (44.8–67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic

    Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

    Get PDF
    BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

    Graphene : a vision to the future of smart E-Textile application

    No full text
    Smart textile is a term referring to the textiles that could interact with their environment, receiving input and giving output based on their applications. Among smart textiles, electrically driven smart textiles (E-textiles) are being produced by various methods and materials integrated with textile substances. Graphene is one of these compounds that could be integrated into the polymer or integrated into the textile materials such as fibres. Therefore, other elements could be doped or immobilised on the graphene nanosheets for a wider range of applications, such as catalytic and electrocatalytic systems.   However, finding the most applicable and efficient method to integrate graphene into the textile fibres and further establishing a method for catalyst immobilisation are challenging and require focused research.   Therefore, this doctoral thesis focused on the innovative concept of integration of graphene and immobilisation of iron nanoparticles on it. Evidence from the systematic experiments was gathered for the case of dip-coating of polyester textiles with graphene oxide dispersion and enhancing the electrostatic bonding between fibres and graphene oxide nanosheets. In the second step, systematic experiments were gathered for the case of immobilisation of an inorganic catalyst (zerovalent iron) on textile supports. The goal of this thesis is to establish the feasibility of a mild and applicable method for textile material supports, which requires low temperature and mild pH, and further fabrication of heterogeneous catalytic and electrocatalytic systems for wastewater treatment. Polyester was chosen as the textile support material for graphene oxide coating and catalyst immobilisation due to its availability and cost-effectiveness.   The thesis has four distinct parts related to (a) Pre-surface-charge modification of the polyester for strong electrostatic bonding between polyester and graphene, (b) Design a continuous yarn coating system for mass production of graphene-coated conductive yarns, (c) Immobilisation of Fe0 on graphene-coated polyester textiles and optimising their feasibility in catalytic systems and (d) Design and prove the feasibility of knitting a fully textile-based reactor having two anodic and cathodic sections by using rGO-Fe0 yarns and stainless-steel multifilament yarns, respectively as a concept of electro-Fenton wastewater treatment.   Diverse analytical and instrumental techniques were used to monitor the surface modification of the polyester textiles and conductivity of the resulting textiles; moreover, the electromechanical and electrothermal properties of the graphene-modified textiles were examined. Further, the efficiency of catalyst immobilisation, physio-chemical properties of the immobilised catalyst, and their catalytical activities in dye removal from the water was studied. Results showed that surface charge modification of polyester fabric with both chitosan and hexadecylpyridinium chloride (HDPC) gives the most homogeneous graphene coating, resulting in high conductivity and very good fastness. Furthermore, results from scanning electron microscope (SEM), Differential scanning calorimetry (DSC), and UV/Visible spectrophotometry prove the success of immobilisation of zerovalent iron on the graphene-modified textiles.  The novelty of the research presented in this doctoral thesis is primarily attributed to the novelty of a hybrid graphene-catalyst immobilisation-grafting on polyester textile supports for wastewater treatment applications. The final concept of the thesis is to introduce the potential for assembling a fully textile-based reactor for Electro-Fenton wastewater treatments

    Graphene : a vision to the future of smart E-Textile application

    No full text
    Smart textile is a term referring to the textiles that could interact with their environment, receiving input and giving output based on their applications. Among smart textiles, electrically driven smart textiles (E-textiles) are being produced by various methods and materials integrated with textile substances. Graphene is one of these compounds that could be integrated into the polymer or integrated into the textile materials such as fibres. Therefore, other elements could be doped or immobilised on the graphene nanosheets for a wider range of applications, such as catalytic and electrocatalytic systems.   However, finding the most applicable and efficient method to integrate graphene into the textile fibres and further establishing a method for catalyst immobilisation are challenging and require focused research.   Therefore, this doctoral thesis focused on the innovative concept of integration of graphene and immobilisation of iron nanoparticles on it. Evidence from the systematic experiments was gathered for the case of dip-coating of polyester textiles with graphene oxide dispersion and enhancing the electrostatic bonding between fibres and graphene oxide nanosheets. In the second step, systematic experiments were gathered for the case of immobilisation of an inorganic catalyst (zerovalent iron) on textile supports. The goal of this thesis is to establish the feasibility of a mild and applicable method for textile material supports, which requires low temperature and mild pH, and further fabrication of heterogeneous catalytic and electrocatalytic systems for wastewater treatment. Polyester was chosen as the textile support material for graphene oxide coating and catalyst immobilisation due to its availability and cost-effectiveness.   The thesis has four distinct parts related to (a) Pre-surface-charge modification of the polyester for strong electrostatic bonding between polyester and graphene, (b) Design a continuous yarn coating system for mass production of graphene-coated conductive yarns, (c) Immobilisation of Fe0 on graphene-coated polyester textiles and optimising their feasibility in catalytic systems and (d) Design and prove the feasibility of knitting a fully textile-based reactor having two anodic and cathodic sections by using rGO-Fe0 yarns and stainless-steel multifilament yarns, respectively as a concept of electro-Fenton wastewater treatment.   Diverse analytical and instrumental techniques were used to monitor the surface modification of the polyester textiles and conductivity of the resulting textiles; moreover, the electromechanical and electrothermal properties of the graphene-modified textiles were examined. Further, the efficiency of catalyst immobilisation, physio-chemical properties of the immobilised catalyst, and their catalytical activities in dye removal from the water was studied. Results showed that surface charge modification of polyester fabric with both chitosan and hexadecylpyridinium chloride (HDPC) gives the most homogeneous graphene coating, resulting in high conductivity and very good fastness. Furthermore, results from scanning electron microscope (SEM), Differential scanning calorimetry (DSC), and UV/Visible spectrophotometry prove the success of immobilisation of zerovalent iron on the graphene-modified textiles.  The novelty of the research presented in this doctoral thesis is primarily attributed to the novelty of a hybrid graphene-catalyst immobilisation-grafting on polyester textile supports for wastewater treatment applications. The final concept of the thesis is to introduce the potential for assembling a fully textile-based reactor for Electro-Fenton wastewater treatments

    Return to Sports Following Lateral Ankle Sprain in Professional Athletes; A Review of Articles: Study of return to sports after Lateral Ankle Sprains

    No full text
    Objective: Lateral ankle sprain (LAS) is one of the most common injuries during physical activity. Considering the high prevalence of this injury in athletes and the need to pay attention to athletes' return to the same level of sports performance as before the injury, the present study aimed to investigate the return to sport after lateral ankle sprains. Materials and Methods: In this study, a comprehensive review of the published papers has been done considering English specialized keywords, including physical therapy, sport-specific movement, return to sport, ankle injuries, ligament injuries, return to play, lower extremity, ankle sprain, recurrent injury, ankle, sports injury, lateral ankle instability, chronic ankle instability, athlete, lateral ankle sprain. Therefore, databases i.e., Science Direct, Scopus, Pedro, Google Scholar, PubMed, SID, ISC, Madlib, Magiran and Irandoc were explored, and those researches published between 2000 to April 2022 about the return to sport and LAS injuries were studied. Findings: After searching in the mentioned databases, first, the abstract of 370 articles on return to sport after LAS was found, and then the full text of 148 related papers was studied. After reviewing them based on the inclusion and exclusion criteria and eliminating duplicate items, 47 articles were scrutinized. Finally, 11 papers were identified about the return to sport after LAS injury. Most studies have reported that the recommended methods reduce the time to return to sport. In this regard, some studies have set a time to return to sport, and some have not reported the exact time. Studies have emphasized the use of specific tests and criteria for evaluating athletes to enter the final stage of rehabilitation as the most important principle of safely returning to sport. Conclusion: Athletes' return to physical activity should be followed in a way that allows them to safely return to sport while minimizing the risk of recurrent injuries. Determining specialized criteria and tests for high and diverse populations in sports, especially those involved with lateral ankle sprains, is the key to success in safer return to sport. However, most studies have been conducted in limited populations and disciplines, and researchers must perform more research in this area
    corecore