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Background: Exchange transfusion (ET) is an effective treatment for acute bilirubin encephalopathy and extreme neonatal hyperbilirubinemia (ENH). It can reduce mortality and morbidity. This study aimed to investigate the trends and risk factors of ENH requiring ET in hospitalized neonates in Iran. Methods: A retrospective analysis of medical records of neonates who underwent ET due to ENH was conducted from 2011 to 2021, in Shiraz, Iran. Clinical records were used to gather demographic and laboratory data. The quantitative data were expressed as mean±SD, and qualitative data was presented as frequency and percentage. P<0.05 was considered statistically significant. Results: During the study, 377 ETs were performed for 329 patients. The annual rate of ET decreased by 71.2% during the study period. The most common risk factor of ENH was glucose-6-phosphate dehydrogenase (G6PD) deficiency (35%), followed by prematurity (13.06%), ABO hemolytic disease (7.6%), sepsis (6.4%), Rh hemolytic disease (6.08%), and minor blood group incompatibility (3.34%). In 28.52% of the cases, the cause of ENH was not identified. 17 (5.1%) neonates had acute bilirubin encephalopathy, of whom 6 (35.29%) had G6PD deficiency, 6 (35.29%) had ABO incompatibility, and 2 (11.76%) had Rh incompatibility. Conclusion: Although the rate of ET occurrence has decreased, it seems necessary to consider different risk factors and appropriate guidelines for early identification and management of neonates at risk of ENH should be developed. The findings of the study highlighted the important risk factors of ENH in southern Iran, allowing for the development of appropriate prevention strategies.
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Transfusão Total , Deficiência de Glucosefosfato Desidrogenase , Hiperbilirrubinemia Neonatal , Humanos , Irã (Geográfico)/epidemiologia , Hiperbilirrubinemia Neonatal/terapia , Hiperbilirrubinemia Neonatal/epidemiologia , Recém-Nascido , Transfusão Total/estatística & dados numéricos , Transfusão Total/métodos , Feminino , Fatores de Risco , Masculino , Estudos Retrospectivos , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/terapia , Kernicterus/epidemiologia , Kernicterus/etiologia , Incompatibilidade de Grupos Sanguíneos/epidemiologia , Incompatibilidade de Grupos Sanguíneos/complicaçõesRESUMO
This paper presents a scalable and straightforward technique for the immediate patterning of liquid metal/polymer composites via multiphase 3D printing. Capitalizing on the polymer's capacity to confine liquid metal (LM) into diverse patterns. The interplay between distinctive fluidic properties of liquid metal and its self-passivating oxide layer within an oxidative environment ensures a resilient interface with the polymer matrix. This study introduces an inventive approach for achieving versatile patterns in eutectic gallium indium (EGaIn), a gallium alloy. The efficacy of pattern formation hinges on nozzle's design and internal geometry, which govern multiphase interaction. The interplay between EGaIn and polymer within the nozzle channels, regulated by variables such as traverse speed and material flow pressure, leads to periodic patterns. These patterns, when encapsulated within a dielectric polymer polyvinyl alcohol (PVA), exhibit an augmented inherent capacitance in capacitor assemblies. This discovery not only unveils the potential for cost-effective and highly sensitive capacitive pressure sensors but also underscores prospective applications of these novel patterns in precise motion detection, including heart rate monitoring, and comprehensive analysis of gait profiles. The amalgamation of advanced materials and intricate patterning techniques presents a transformative prospect in the domains of wearable sensing and comprehensive human motion analysis.
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In emergency treatment research, the focus on chitosan-based products for wound healing has been consistent. This study specifically explores a dressing made by mixing chitosan (CS) and poly (vinyl alcohol) PVA. Using electrospinning technology, nanofiber membranes of CS and PVA are created with the assistance of non-toxic and hydrophilic polyethylene oxide (PEO). The outcome is a new nanofibrous membrane loaded with mupirocin, designed for healing burn wounds. The study delves into the influence of PVA, CS, and PEO concentrations on the structural and chemical characteristics of the mats. This comprehensive exploration involves techniques such as Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM) imaging, Fourier Transform Infrared Spectrometry (FTIR analysis), and Contact angle measurements. Additionally, the research evaluates the antibacterial performance and biomedical behavior of the developed scaffolds. PEO proves beneficial in the electrospinning process, contributing to smoother fibers. Meanwhile, the addition of CS and mupirocin leads to formation of the thinner nanofibers (251 ± 5 µm and 263 ± 4 µm, respectively) and scaffolds with higher swelling (up to â¼3.5 times at 90 min). Notably, the (MTT) assay confirms the non-cytotoxicity of the fabricated nanofibers, with proliferations exceeding â¼85% for all samples. The crosslinked samples released the drug more slowly than the non-crosslinked dressings, with 80% of the scaffolds releasing the drug within 24 h. The in-vivo investigations suggested that the drug-containing scaffolds performed reliably and showed promise as a medical dressing for treating burn wounds.
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Queimaduras , Quitosana , Nanofibras , Humanos , Mupirocina , Quitosana/química , Nanofibras/química , Polietilenoglicóis/química , Antibacterianos/química , Bandagens , Queimaduras/tratamento farmacológico , Álcool de Polivinil/químicaRESUMO
Neurological disorders are a major group of non-communicable diseases affecting quality of life. Non-Coding RNAs (ncRNAs) have an important role in the etiology of neurological disorders. In studies on the genesis of neurological diseases, aquaporin 4 (AQP4) expression and activity have both been linked to ncRNAs. The upregulation or downregulation of several ncRNAs leads to neurological disorder progression by targeting AQP4. The role of ncRNAs and AQP4 in neurological disorders is discussed in this review.
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MicroRNAs , Doenças do Sistema Nervoso , Humanos , Aquaporina 4/genética , Aquaporina 4/metabolismo , Qualidade de Vida , RNA não Traduzido/metabolismo , Doenças do Sistema Nervoso/genética , Regulação para BaixoRESUMO
To improve farming productivity, a large number of pesticides have been used worldwide in recent decades, leading to the pollution of soil, agri-products, and water, directly/indirectly affecting human health. In this regard, many studies were conducted in different countries on residual pesticides in the environment. In the current study, residual pesticides including chlorpyrifos, cypermethrin, diazinon, malathion, and metalaxyl in tomatoes were meta-analyzed and health risk of consumers was estimated. For this purpose, based on a systematic review, data from 47 studies were extracted and meta-analyzed, and the health impact of pooled concentrations was assessed via a health risk method. According to the results, metalaxyl had the most concentration followed by malathion, cypermethrin, diazinon, and chlorpyrifos, respectively. The non-carcinogenic risk (n-CR) was calculated from crop consumption also showed that exposure to malathion has the most risk. Among the investigated communities, Iranian consumers were in considerable health risk (THQ > 1). Considering that the potential for the use of pesticides will increase with the need for food in the future, hence, governments must manage the usage by governments via alternative methods such as cultural, biological, physical, and genetic modifications.
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Clorpirifos , Praguicidas , Solanum lycopersicum , Humanos , Praguicidas/análise , Clorpirifos/análise , Diazinon/análise , Malation , Irã (Geográfico) , Medição de RiscoRESUMO
Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented.
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Membrane-based salinity gradient energy generation from the osmotic potential at the interface of a river and seawater through reverse electrodialysis is a promising route for realizing clean, abundant, and sustainable energy. Membrane permeability and selective ion transport are crucial for efficient osmotic energy harvesting. However, balancing these two parameters in the membrane design and synthesis remains challenging. Herein, a hybridized bilayer metal-organic frameworks (MOF-on-MOF) membrane is fabricated for efficient transmembrane conductance for enhanced osmotic power generation. The heterogeneous membrane is constructed from imidazolate framework-8 (ZIF-8) deposited on a UiO-66-NH2 membrane intercalated with poly(sodium-4-styrenesulfonate) (PSS). The angstrom-scale cavities in the ZIF-8 layer promote ion selectivity by size exclusion, and the PSS-intercalated UiO-66-NH2 film ensures cation permeability. The synergistic effect is a simultaneous improvement in ion transport and selectivity from an overlapped electric double layer generating 40.01 W/m2 and 665 A/m2 permeability from a 500-fold concentration gradient interface at 3 KΩ and 9.20 W/m2 from mixing of real sea-river water. This work demonstrates a rational design strategy for hybrid membranes with improved ion selectivity and permeability for the water-energy nexus.
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Despite being a pillar of high-performance materials in industry, manufacturing carbon fiber composites with simultaneously enhanced multifunctionality and structural properties has remained elusive due to the lack of practical bottom-up approaches with control over nanoscale interactions. Guided by the droplet's internal currents and amphiphilicity of nanomaterials, herein, a programmable spray coating is introduced for the deposition of multiple nanomaterials with tailorable patterns in composite. It is shown that such patterns regulate the formation of interfaces, damage containment, and electrical-thermal conductivity of the composites, which is absent in conventional manufacturing that primarily rely on incorporating nanomaterials to achieve specific functionalities. Molecular dynamics simulations show that increasing the hydrophilicity of the hybrid nanomaterials, which is synchronous with shifting patterns from disk to ring, improves the interactions between the carbon surfaces and epoxy at the interfaces,manifested in enhanced interlaminar and flexural performance. Transitioning from ring to disk creates a larger interconnected network leading to improved thermal and electrical properties without penalty in mechanical properties. This novel approach introduces a new design , where the mechanical and multifunctional performance is controlled by the shape of the deposited patterns, thus eliminating the trade-off between properties that are considered paradoxical in today's manufacturing of hierarchical composites.
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This study presents a systematic study on sequential treatment of highly resistant landfill leachate by electrocoagulation (EC)/aeration, sulfate radical advanced oxidation process (SR-AOP) and electro-Fenton (EF). In case of SR-AOP, peroxymonosulfate (PMS) catalyzed by zero valent iron (ZVI) and ultraviolet irradiation (UV) system was developed. Treatment process was optimized in respect to COD removal. Analysis of results revealed that sequential application of EC/aeration, PMS/ZVI/UV, and EF processes provide an extraordinary performance and meet the environmental regulations. The source of iron for EF process was provided from previous process reducing the cost of sequential process. Separately, EC/aeration (inlet COD = 4040 mg/L), PMS/ZVI/UV (inlet COD = 1560 mg/L), and EF (inlet COD = 471 mg/L) removed 61, 69 and 82% of COD respectively. Overall, sequential processes of EC/aeration, PMS/ZVI/UV and EF could remove the COD, TOC and ammonia of the landfill leachate around 98%, 93% and 94%, respectively. The comparison of different sequences of following processes indicated that current configuration (EC/aeration-PMS/ZVI/UV-EF) could meet the discharge standards. Furthermore, humification degree was significantly improved after oxidative processes. Biodegradability study was also performed by means of BOD/COD, average oxidation state (AOS), and Zahn-Wellens test, and the best results associated with these indices were obtained 0.56, 2.37, and over 98%, respectively. Phytotoxicity of leachate was remarkably reduced and the final effluent can be considered as a non-phytotoxic wastewater.
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Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Ferro , Peróxido de Hidrogênio , Oxirredução , EletrocoagulaçãoRESUMO
An infected skin wound caused by external injury remains a serious challenge. Electrospun drug-loaded nanofibers with antibacterial properties based on biopolymers have been widely explored for wound healing. In this study, the double-layer CS/PVA/mupirocin (CPM) + CS/PVA/bupivacaine (CPB) mats were prepared by electrospinning method (20 % polymer weight) and then crosslinked with glutaraldehyde (GA) to optimize the water-resistant and biodegradation properties for wound dressing applications. The morphology of mats was characterized as defect-free and interconnected nanofibers by Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM). Fourier Transform Infrared Spectrometry (FTIR) analysis also assessed the chemical structural properties. The porosity, surface wettability, and swelling degree of the dual-drug loaded mats were improved by about 20 %, 12°, and 200 % of the CS/PVA sample to provide a moist environment for efficient wound breathing and repairing. This highly porous mat facilitated the wound exudates absorption and air permeability excellently, reducing the chance of bacterial infections by inhibiting the growth of S. aureus bacterial colonies with a zone of 71.3 mm diameter. In vitro drug release results showed a high-burst release of 80 % and a continuous release profile for bupivacaine and mupirocin, respectively. MTT assay and in vivo tests indicated >90 % of cell viability and improvement in cell proliferation. It triply accelerated wound closure compared to the control group, reaching nearly full closure after 21 days as a potential clinical wound treatment.
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Quitosana , Nanofibras , Mupirocina/farmacologia , Quitosana/química , Álcool de Polivinil/química , Nanofibras/química , Bupivacaína/farmacologia , Liberação Controlada de Fármacos , Staphylococcus aureus , Antibacterianos/química , BandagensRESUMO
Potential toxic element (PTE) contamination in the Persian Gulf has become an important health concern in recent decades. This investigation aimed to meta-analyses of potential toxic elements including lead (Pb), inorganic arsenic (As), cadmium (Cd), nickel (Ni), and mercury (Hg) in the coastal sediment of the Persian Gulf. In this study, an attempt was made to retrieve papers conducted on the concentration of PTE in the coastal sediment of the Persian Gulf by searching in international databases including Web of Science, Scopus, Embase, and PubMed. Meta-analysis concentration of PTE in the coastal sediment of the Persian Gulf was conducted using random effects model based on the country subgroup. Additionally, non-dietary risk assessment including non-carcinogenic and carcinogenic risks from ingestion, inhalation and dermal contact routes and ecological risk assessment was estimated. Seventy-eight papers with 81 data-reports (1650 sample size) were included in our meta-analysis. The rank order of heavy metals in coastal sediment of the Persian Gulf based on pooled concentration was Ni (65.44 mg/kg) > Pb (58.35 mg/kg) > As (23.78 mg/kg) > Cd (1.75 mg/kg) > Hg (0.77 mg/kg). The highest concentration of As, Cd, Pb, Ni, and Hg was observed in the coastal sediment of Saudi Arabia, Arab Emirates, Qatar, Iran, and Saudi Arabia, respectively. Although the Igeo index in coastal sediment of the Persian Gulf was in grade 1 (uncontaminated) and grade 2 (slightly contaminated) but total target hazard quotient (TTHQ) of adults and adolescent was higher than 1 value in Iran, Saudi Arabic, United Arab Emirates, and Qatar. Total cancer risk (TCR) for adults and adolescent due to As was higher than 1E-6 in Iran, United Arab Emirates, and Qatar but TCR for adolescents due to As was higher than 1E-6 in Saudi Arabic. Therefore, it is recommended to monitor the concentration of PTE and implementation of programs to reduce the emission of PTE from resources in the Persian Gulf.
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Mercúrio , Metais Pesados , Poluentes Químicos da Água , Adolescente , Adulto , Humanos , Cádmio/análise , Monitoramento Ambiental , Sedimentos Geológicos/análise , Oceano Índico , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Níquel/análise , Receptores de Antígenos de Linfócitos T , Medição de Risco , Poluentes Químicos da Água/análiseRESUMO
As fused filament fabrication (FFF) continues to gain popularity, many studies are turning to nanomaterials or optimization of printing parameters to improve the materials' properties; however, many overlook how materials formulation and additive manufacturing (AM) processes cooperatively engineer the evolution of properties across length scales. Evaluating the in-process evolution of the nanocomposite using AM will provide a fundamental understanding of the material's microstructure, which can be tailored to create unique characteristics in functionality and performance. In this study, the crystallinity behavior of polyetheretherketone (PEEK) was studied in the presence of carbon nanotubes (CNTs) as a nucleation aid for improved crystallization during FFF processing. Using various characterization techniques and molecular dynamics simulations, it was discovered that the crystallization behavior of extruded filaments is very different from that of 3D printed roads. Additionally, the printed material exhibited cold crystallization, and the CNT addition increased the crystallization of printed roads, which were amorphous without CNT addition. Tensile strength and modulus were increased by as much as 42 and 51%, respectively, due to higher crystallinity during printing. Detailed knowledge on the morphology of PEEK-CNT used in FFF allows gaining a fundamental understanding of the morphological evolution occurring during the AM process that in turn enables formulating materials for the AM process to achieve tailored mechanical and functional properties, such as crystallinity or conductivity.
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BACKGROUND: Peripheral T-Cell Lymphoma Not Otherwise Specified (PTCL-NOS) is a rare type of non-Hodgkin T-cell lymphoma which frequently seen in immunocompromised individuals. It is estimated that only 2% of lymphomas are located on the buccal mucosa. In this case report, we present a 34-year-old male with a PTCL diagnosis. CASE: A 34-year-old immune-competent male presented with a buccal progressive ulcerated lesion. Histopathologic and immunohistochemical findings were compatible with PTCL-NOS and classified as stage IIEA according to the Ann Arbor staging. The patient underwent chemotherapy followed by radiotherapy. He remained disease-free after 12 months of follow-up. CONCLUSION: Although lymphoma is uncommon in the oral cavity, physicians especially dentists in ordinary dental checkups should consider persistent progressive lesions as an important differential diagnosis of lymphoma.
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Linfoma de Células T Periférico , Neoplasias Bucais , Adulto , Humanos , Masculino , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/radioterapia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/radioterapia , Intervalo Livre de Doença , SeguimentosRESUMO
Introduction: Textured soy protein (TSP) and nuts are two processed forms of soybean (Glycine max L.) that are widely consumed for nutritional purposes in Iran. Recently, we have reported the antioxidant and anticholinesterase effects of raw soybean (RS) attributed to isoflavones, such as genistein. In this work, we aimed to compare in vitro antioxidant and anticholinesterase effects of TSP, nuts, and RS to select the most effective one for learning capacity and spatial memory studies. Methods: Genistein content was determined using high-performance thin layer chromatography (HPTLC), while diphenylpicrylhydrazil (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) were used to study antioxidant evaluation and Ellman's colorimetric method was used to measure anticholinesterase. TSP extract (TSPE) was administered to male rats (100 mg/kg, 200 mg/kg and 400 mg/kg, intraperitoneally [i.p] for 7 days) before scopolamine injection (1 mg/kg). Learning capacity and spatial memory were evaluated using passive avoidance test (PAT) and Morris water maze (MWM) methods compared to physostigmine and piracetam. Results: The greatest antioxidant and anticholinesterase effect was observed for TSPE, which significantly prolonged initially latency in PTA (P<0.05) and improved all indicators in the MWM test at 200 mg/kg. Conclusion: The memory-improving effect of TSPE may be due to its antioxidant and anticholinesterase effect as well as neuroprotective effects of its isoflavones. Highlights: Different samples (nuts-raw soybeans-TSP) prepared from soybeans.All samples exhibited antioxidant and anti-cholinesterase effects in vitro studies.TSP showed the most biological activity and the greatest genistein content.TSP significantly improved memory and learning indicators at 200 mg/kg.These effects are attributed to its antioxidant and anticholinesterase activity.Plant isoflavones have neuroprotective effects. Plain Language Summary: Alzheimer's disease (AD), is one of the problems of the elderly society, which has a lot of emotional and financial costs. AD is a type of progressive brain disease in which neurons are destroyed and memory is lost. This disease currently has no definitive treatment and the only way is to prevent the disease from spreading. Much research has been devoted to finding suitable and effective treatments for AD. Many food and herbal medicines have shown to be effective in controlling this disease. Soybean is a plant that is widely used as food and snacks in Iran in different ways. In this study, we prepared three preparation from soya beans which have been widely used by Iranian people including raw soya, nut (roasted form) and textured soy protein (TSP). The effect of these preparations have been studied on memory and learning in amnestic rats through different pharmacological studies. The results indicated that TSP due to antioxidant and anticholinesterase activity significantly can augment memory enhancing and learning ability Alzheimer's disease (AD), is one of the problems of the elderly society, which has a lot of emotional and financial costs. AD is a type of progressive brain disease in which neurons are destroyed and memory is lost. This disease currently has no definitive treatment and the only way is to prevent the disease from spreading. Much research has been devoted to finding suitable and effective treatments for AD. Many food and herbal medicines have shown to be effective in controlling this disease. Soybean is a plant that is widely used as food and snacks in Iran in different ways. In this study, we prepared three preparation from soya beans which have been widely used by Iranian people including raw soya, nut (roasted form) and textured soy protein (TSP). The effect of these preparations have been studied on memory and learning in amnestic rats through different pharmacological studies. The results indicated that TSP due to antioxidant and anticholinesterase activity significantly can augment memory enhancing and learning ability. TSP also contains some phytochemicals such as phytoestrogens which have shown neuroprotective activity in different studies.
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It is important to increase the awareness and knowledge of head and neck surgeons about the recent surge of craniofacial mucormycosis in COVID-19 patients because early diagnosis and appropriate treatment are essential to improve the outcomes. Here, we describe clinical features, treatment protocols, and outcomes of treatment in eight patients with COVID-19-associated mucormycosis in the maxilla. Consistent with the findings of previous studies, our experience in the management of these eight patients shows that early administration of amphotericin B and prompt aggressive surgery are essential for optimal control of the disease.
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Dispersing carbon nanomaterials in solvents is effective in transferring their significant mechanical and functional properties to polymers and nanocomposites. However, poor dispersion of carbon nanomaterials impedes exploiting their full potential in nanocomposites. Cellulose nanocrystals (CNCs) are promising for dispersing and stabilizing pristine carbon nanotubes (pCNTs) and graphene nanoplatelets (pGnP) in protic media without functionalization. Here, the underlying mechanisms at the molecular level are investigated between CNC and pCNT/pGnP that stabilize their dispersion in polar solvents. Based on the spectroscopy and microscopy characterization of CNCpCNT/pGnP and density functional theory (DFT) calculations, an additional intermolecular mechanism is proposed between CNC and pCNT/pGnP that forms carbonoxygen covalent bonds between hydroxyl end groups of CNCs and the defected sites of pCNTs/pGnPs preventing re-agglomeration in polar solvents. This work's findings indicate that the CNC-assisted process enables new capabilities in harnessing nanostructures at the molecular level and tailoring the performance of nanocomposites at higher length scales.
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Nanocompostos , Nanopartículas , Nanotubos de Carbono , Celulose/química , Nanocompostos/química , Nanopartículas/química , Solventes , ÁguaRESUMO
One-piece bearing is the latest type of total disc replacement (TDR) design that is used for the treatment of lumbar degenerative disc disease (DDD). Due to the unique properties of the shape memory polymers (SMPs), such as self-healing, shape-memory, adhesion control, and self-deployable ability, they may be a good candidate for the core of such a design. The purpose of the present study is to use an analytical method combined with a numerical analysis (finite element analysis (FEA)) to determine the mechanical responses of an SMP intervertebral disc (IVD) model, under pure torsion (axial rotation) and pure compression, two loading conditions to which natural intervertebral discs (IVDs) are subjected in vivo. We considered the SMP IVD model to be positioned at L4-L5 because most cases of lumbar DDD are reported at this segment. For the analytical method, an appropriate constitutive equation for an SMP was determined and, then, an analytical solution for the torsional response of a circular SMP IVD model, in a full cycle of stress-free strain recovery, was derived. The developed equations were implemented in finite element modeling to determine responses of the IVD disc model under pure torsion. Additionally, responses of the SMC IVD model, under a compressive load, and different conditions were determined. The analytical and FEA results were compared to experimental results give in the literature for intact lumbar spine segments as the core in a one-piece lumbar TDR. Based on this study, we suggest that SMPs can be used for TDR, as they are strong enough to bear the torsional and compressive loads that IVD is subjected through its life.
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Degeneração do Disco Intervertebral , Disco Intervertebral , Materiais Inteligentes , Substituição Total de Disco , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgiaRESUMO
Electronic textiles have become a dynamic research field in recent decades, attracting attention to smart wearables to develop and integrate electronic devices onto clothing. Combining traditional screen-printing techniques with novel nanocarbon-based inks offers seamless integration of flexible and conformal antenna patterns onto fabric substrates with a minimum weight penalty and haptic disruption. In this study, two different fabric-based antenna designs called PICA and LOOP were fabricated through a scalable screen-printing process by tuning the conductive ink formulations accompanied by cellulose nanocrystals. The printing process was controlled and monitored by revealing the relationship between the textiles' nature and conducting nano-ink. The fabric prototypes were tested in dynamic environments mimicking complex real-life situations, such as being in proximity to a human body, and being affected by wrinkling, bending, and fabric care such as washing or ironing. Both computational and experimental on-and-off-body antenna gain results acknowledged the potential of tunable material systems complimenting traditional printing techniques for smart sensing technology as a plausible pathway for future wearables.
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Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Eletrônica , Humanos , TêxteisRESUMO
This study aimed to investigate spatial distribution, correlations among elements and ecological and probabilistic health risk assessment in smaller than 75 µm street dust in Kerman city, Iran. Street dust samples were collected from 35 different points. Elements were detected by ICP-AES. Pollution degree was characterized through Enrichment Factor (EF), Contamination Factor (CF), Geo-accumulation Index (Igeo) and Potential Ecological Risk (PER). The health risk was assessed using the Monte Carlo simulation method. The mean values of elements were in the order of Al > Mn > Zn > Cu > V > Pb > Cr > Ni > Li > As > Co > Mo > Sb > Cd > Ag. The results of Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) showed that Al, As, Co, Li, Mn and V were possibly derived from natural sources (local soil), while traffic and mining activities were proposed as the main source of Cd, Cr, Cu, Mo, Ni, Pb, Sb and Zn. The order of EF and CF mean values decreased as follows: Mn > Ag > Cu > Zn > Pb > Sb > Mo > Li > Co > V > Cd > As > Cr > Ni. In addition, 73% of Cu and 35% of Zn, Ag and Mn had significant enrichment in the street dust samples. Also, Ag and Mn were categorized in the significant and very significant pollution category. In terms of the PER index, all samples could be classified at low-risk category. Ingestion of street dust was the significant route for exposure of residents of Kerman to the elements studied. No significant ecological hazards and health risks were observed from street dust in the study area in the period of the study. The improvement in the fuels quality and development of green spaces can be suggested to control natural and anthropogenic street dust pollution sources in the Kerman city.
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Poeira/análise , Poluentes Ambientais/análise , Cidades , Monitoramento Ambiental , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Humanos , Irã (Geográfico) , Metais Pesados/análise , Tamanho da Partícula , Medição de RiscoRESUMO
Three main parameters affecting TiO2/SiO2/Fe3O4 nanoparticles activity in photocatalytic degradation of methyl orange were investigated using response surface methodology (SRM). Precipitation method and sol-gel technique were used to prepare SiO2/Fe3O4 electromagnetic composite support and TiO2/SiO2/Fe3O4 photocatalytically active nanoparticles. The specific surface area, pore volume, and average pore size of the synthesized nanoparticles were respectively equal to 56 m2/g, 0.12 cm3/g and 9.4 nm. The point of zero charge (PZC) of the catalyst was measured to be 5.9. The maximum and minimum photocatalytic degradation of methyl orange using the synthesized nanoparticles were 100% and 30%, respectively. A linear model was fitted to the obtained results with R2adjusted equal to 0.87. The results of analysis of variance (ANOVA) revealed that catalyst concentration, reaction media pH and aeration rate were significantly affected the photocatalytic activity. Optimization was performed considering photocatalytic activity as the main objective functions. In order to maximize photocatalytic activity, catalyst loading, reaction media pH and aeration rate were respectively adjusted to 2,000 ppm, 3 and 2.5 L/min, which resulted in total methyl orange removal. Considering promising photocatalytic activity of TiO2/SiO2/Fe3O4 along with core-sell nanocomposite separation performance led us to propose this photocatalyst as an alternative solution for treating waste waters.