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3.
Epileptic Disord ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949266

RESUMEN

OBJECTIVE: Epileptic spasms (ES) can be caused by a variety of etiologies. However, in almost half of cases, the etiology is unidentified. With the advent of next-generation sequencing (NGS), the recognition of genetic etiologies has increased. METHODS: We retrospectively reviewed the medical records of patients with ES who were evaluated in the comprehensive epilepsy program at King Fahad Specialist Hospital Dammam between 2009 and 2022. RESULTS: Our data show that in 57.7% of patients with ES, the etiology was unidentified after a standard clinical evaluation and neuroimaging. Of these patients, n = 25 (35.2%) received a genetic diagnosis after some form of genetic testing, and 3.1% of patients from specialized metabolic work indicated the need for genetic testing to confirm the diagnosis. Karyotyping led to a diagnosis in 3.6% of patients, and chromosomal microarray led to a diagnosis in 7.1%. An NGS epilepsy gene panel (EP) was done for 45 patients, leading to a diagnosis in 24.4% (n = 11). Exome sequencing was done for 27 patients, including n = 14 with non-diagnostic panel testing; it led to a diagnosis in 37.3% (n = 10). Exome sequencing led to a diagnosis in 61.5% of patients without a previous panel test and in only two patients who had previously had a negative panel testing. SIGNIFICANCE: In this article, we present the diagnostic evaluations of ES for a cohort of 123 patients and discuss the yield and priority of NGS for evaluating ES. Our findings suggest that exome sequencing has a higher diagnostic yield for determining the etiology of ES in patients for whom the etiology is still unclear after an appropriate clinical assessment and a brain MRI.

4.
RSC Adv ; 14(28): 20230-20239, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38919283

RESUMEN

Nickel ferrite nanoparticles (NFNPs) were synthesized in an alkaline medium (pH ∼ 11) using a wet chemical co-precipitation technique. To probe the effect of surfactants on the surface morphology, particle size and size distribution of nanoparticles; two surfactants, namely, cetyl trimethyl ammonium bromide (CTAB) and sodium dodecyl sulphate (SDS), were applied. The native and surfactant-assisted nickel ferrite NPs were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The addition of surfactants (CTAB/SDS) effectively controlled the secondary growth of nickel ferrite particles and reduced their size, as examined by XRD, AFM, DLS, SEM and TEM. Characterization technique results affirmed that CTAB is a more optimistic surfactant to control the clustering, dispersion and particle size (∼22 nm) of NFNPs. To identify the impact of ferrite particle size on charge storage devices, their electrochemical properties were studied by using cyclic voltammetry (CV), galvanic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) in 1 M KOH electrolyte through three-electrode assembly. NiFe2O4@CTAB showed a specific capacity of 267.1 C g-1, specific capacitance of 593.6 F g-1 and energy density of 16.69 W h kg-1, which was far better than the performances of other synthesized native NFNPs and NiFe2O4@SDS having larger surface areas.

5.
Front Bioeng Biotechnol ; 12: 1352170, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38567083

RESUMEN

Research has demonstrated the benefits of transcranial magnetic stimulation (TMS) in rehabilitation. TMS has been widely used in clinical and research settings for individuals with and without neurological dysfunctions. Therefore, understanding the knowledge and attitudes of rehabilitation specialists regarding TMS is crucial for its application. To our knowledge, no such studies have previously been conducted in the rehabilitation field. Therefore, this study is the first to assess rehabilitation specialists' knowledge of and attitudes toward TMS. An observational cross-sectional study using a self-administered online survey was conducted among 102 rehabilitation specialists to assess their knowledge and attitudes regarding TMS application in rehabilitation sciences. Descriptive and inferential statistics were used to describe the knowledge and attitudes of rehabilitation specialists toward TMS and examine the impact of different factors such as gender, education level, acceptability, and practice on these outcomes. Rehabilitation specialists who participated in this study showed a limited level of general knowledge of TMS in rehabilitation (7.81 ± 6.20, 37.19%). However, a significant association between educational levels and knowledge was found. Higher knowledge scores were observed for specialists with post-graduate degrees compared to those with only a bachelor's degree. Moreover, knowledge level, experience, and availability of TMS equipment in the workplace led to a positive attitude toward TMS among rehabilitation specialists. A low knowledge level among rehabilitation specialists was attributed to their level of education. Nevertheless, specialists showed an overall positive attitude toward TMS. Therefore, customized medical education is necessary to incorporate TMS theory and applications into neuroscience and rehabilitation courses for rehabilitation specialists as it holds significant promise as a therapeutic tool.

6.
Neuropediatrics ; 55(3): 166-170, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38365197

RESUMEN

AIM: The study aims to review all the genetically confirmed STAC3-related myopathy being followed in a single center in the Eastern Province of Saudi Arabia. METHODOLOGY: A retrospective review of all genetically confirmed STAC3-related myopathy followed in our clinic has been conducted. RESULTS: 7 patients with STAC3-related myopathy have been found in our cohort, with all the patients presenting with infantile hypotonia, myopathic facies, and muscle weakness in the first year of life. Feeding difficulties and failure to thrive were found in all patients except one who died during the neonatal period. Respiratory muscle involvement was also found in 5 out of 6 formally tested patients while cleft palate was found in 5 patients. CONCLUSION: STAC3-related myopathy is a relatively rare, malignant hyperthermia (MH)--causing muscle disease described in specific, highly consanguineous populations. Making the diagnosis in myopathic patients with cleft palate preoperatively can prevent MH-induced, anesthesia-related perioperative complications.


Asunto(s)
Enfermedades Musculares , Humanos , Estudios de Cohortes , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/etiología , Estudios Retrospectivos , Arabia Saudita
7.
Sensors (Basel) ; 24(4)2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38400473

RESUMEN

Microwave medical imaging (MMI) is experiencing a surge in research interest, with antenna performance emerging as a key area for improvement. This work addresses this need by enhancing the directivity of a compact UWB antenna using a Yagi-Uda-inspired reflector antenna. The proposed reflector-loaded antenna (RLA) exhibited significant gain and directivity improvements compared to a non-directional reference antenna. When analyzed for MMI applications, the RLA showed a maximum increase of 4 dBi in the realized gain and of 14.26 dB in the transmitted field strength within a human breast model. Moreover, it preserved the shape of time-domain input signals with a high correlation factor of 94.86%. To further validate our approach, another non-directional antenna with proven head imaging capabilities was modified with a reflector, achieving similar directivity enhancements. The combined results demonstrate the feasibility of RLAs for improved performance in MMI systems.


Asunto(s)
Imágenes de Microonda , Microondas , Humanos , Diagnóstico por Imagen , Radiografía
8.
J Alzheimers Dis ; 99(s1): S5-S22, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38339930

RESUMEN

Aging is an intrinsic aspect of an organism's life cycle and is characterized by progressive physiological decline and increased susceptibility to mortality. Many age-associated disorders, including neurological disorders, are most commonly linked with the aging process, such as Alzheimer's disease (AD). This review aims to provide a comprehensive overview of the effects of aging and AD on the molecular pathways and levels of different proteins in the brain, including metalloproteins, neurotrophic factors, amyloid proteins, and tau proteins. AD is caused by the aggregation of amyloid proteins in the brain. Factors such as metal ions, protein ligands, and the oligomerization state of amyloid precursor protein significantly influence the proteolytic processing of amyloid-ß protein precursor (AßPP). Tau, a disordered cytosolic protein, serves as the principal microtubule-associated protein in mature neurons. AD patients exhibit decreased levels of nerve growth factor within their nervous systems and cerebrospinal fluid. Furthermore, a significant increase in brain-derived neurotrophic factor resulting from the neuroprotective effect of glial cell line-derived neurotrophic factor suggests that the synergistic action of these proteins plays a role in inhibiting neuronal degeneration and atrophy. The mechanism through which Aß and AßPP govern Cu2+ transport and their influence on Cu2+ and other metal ion pools requires elucidation in future studies. A comprehensive understanding of the influence of aging and AD on molecular pathways and varying protein levels may hold the potential for the development of novel diagnostic and therapeutic methods for the treatment of AD.


Asunto(s)
Envejecimiento , Enfermedad de Alzheimer , Encéfalo , Humanos , Envejecimiento/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Proteínas tau/metabolismo
9.
ChemSusChem ; 17(2): e202300876, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-37695539

RESUMEN

Carbon-based materials have emerged as promising anodes for sodium-ion batteries (SIBs) due to the merits of cost-effectiveness and renewability. However, the unsatisfactory performance has hindered the commercialization of SIBs. During the past decades, tremendous attention has been put into enhancing the electrochemical performance of carbon-based anodes from the perspective of improving the compatibility of electrolytes and electrodes. Hence, a systematic summary of strategies for optimizing electrolytes between hard carbon, graphite, and other structural carbon anodes of SIBs is provided. The formulations and properties of electrolytes with solvents, salts, and additives added are comprehensively presented, which are closely related to the formation of solid electrolyte interface (SEI) and crucial to the sodium ion storage performance. Cost analysis of commonly used electrolytes has been provided as well. This review is anticipated to provide guidance in future rational tailoring of electrolytes with carbon-based anodes for sodium-ion batteries.

10.
CNS Neurol Disord Drug Targets ; 23(4): 463-467, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37026496

RESUMEN

Epilepsy is one of the most common and devastating neurological disorders that causes unprovoked, recurrent seizures arising from excessive synchronized neuronal discharging. Although antiepileptic drugs (AEDs) reduce the frequency of epilepsy seizures, drug-refractory epileptic patients exert resistance to AEDs, resulting in treatment difficulty. Moreover, pharmacological treatments do not show satisfactory results in response to photosensitive epilepsy. In the recent era, light therapy emerged as a potential non-pharmacological approach for treating various diseases, including depression, seasonal affective disorders, migraine, pain, and others. Several studies have also shown the potential of light therapy in treating epilepsy. In addition, Red light evokes epilepsy seizures. Blue lenses filter the red light and significantly suppress the frequency of epilepsy seizures. However, the effects of green light on the frequency of epileptic seizures are not studied yet. In addition, light-activated gene therapy or optogenetics also emerged as a possible option for epilepsy treatment. Animal models have shown the therapeutic possibilities of optogenetics and light therapy; however, human studies addressing this possibility are still vague. This review provides the beneficial effects of light in reducing seizure frequency in epilepsy patients. A limited number of studies have been reported so far; therefore, light therapy for treating epilepsy requires more studies on animal models to provide precise results of light effects on seizures.


Asunto(s)
Epilepsia Generalizada , Epilepsia , Trastornos Migrañosos , Animales , Humanos , Epilepsia/tratamiento farmacológico , Convulsiones/tratamiento farmacológico , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/efectos adversos , Epilepsia Generalizada/tratamiento farmacológico , Trastornos Migrañosos/tratamiento farmacológico
11.
Childs Nerv Syst ; 40(3): 957-960, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37943342

RESUMEN

Malformations of cortical development such as polymicrogyria can cause medically refractory epilepsy. Epilepsy surgery (hemispherotomy) can be a good treatment option. In recent years, navigated transcranial magnetic stimulation (nTMS), a noninvasive brain mapping technique, has been used to localize the eloquent cortex for presurgical evaluation of patients with epilepsy. In the present case study, neurophysiological markers of the primary motor cortex (M1), including resting motor threshold (rMT), motor evoked potentials (MEPs), and silent period (SP), were assessed in both hands of a right-handed 10-year-old girl with a history of epilepsy and right hemispheric polymicrogyria. Bilateral MEPs with short latencies were elicited from the contralesional side. The average MEP amplitude and the latency for the patient's paretic and non-paretic hands differed significantly. We conclude that nTMS is a safe and tolerable procedure that can be used for presurgical evaluation in children with intractable epilepsy.


Asunto(s)
Neoplasias Encefálicas , Epilepsia Refractaria , Epilepsias Parciales , Epilepsia , Corteza Motora , Polimicrogiria , Femenino , Niño , Humanos , Estimulación Magnética Transcraneal/métodos , Neoplasias Encefálicas/cirugía , Potenciales Evocados Motores , Corteza Motora/fisiología , Mapeo Encefálico/métodos , Epilepsia Refractaria/etiología , Epilepsia Refractaria/cirugía
12.
Brain Neurorehabil ; 16(3): e33, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38047094

RESUMEN

This case study describes a patient who experienced motor recovery and involuntary movements following damage to the right primary somatosensory cortex caused by an intracranial hemorrhage. The patient initially suffered from paralysis in her left arm and leg, but exhibited significant motor recovery later, accompanied by multiple episodes of ballistic movement during the recovery process. A diffusion tensor imaging analysis was performed to investigate changes in sensorimotor-related brain areas in the patient. The patient had higher fractional anisotropy and lower mean diffusivity values in the ipsilesional red nucleus (RN) than age-matched controls. We assume that hyperactivity of the ipsilesional RN might play a role in motor recovery after damage to the primary somatosensory cortex, potentially through its involvement in sensorimotor integration. Our findings demonstrated the potential for adaptive changes in the ipsilesional RN following damage to the primary somatosensory cortex.

13.
Brain Neurorehabil ; 16(3): e34, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38047103

RESUMEN

Delayed encephalopathy (DE) following acute carbon monoxide (CO) poisoning is characterized by a wide range of neurological symptoms, including akinetic mutism, cognitive impairment, and gait disturbances. Herein, we reported the case of a 61-year-old patient with DE after acute CO poisoning, who displayed heterogeneous patterns of cortical and subcortical structural integrity on diffusion tensor imaging (DTI). Four distinct patterns of diffusion tensor metrics (fractional anisotropy [FA] and mean diffusivity [MD]) were observed in the patient compared to age-matched controls (a decrease in FA and an increase in MD, a decrease in FA only, an increase in MD only, and an increase in FA and MD). This study revealed heterogeneous patterns of cortical and subcortical damage associated with DE after CO poisoning, contributing to a deeper understanding of the diverse clinical symptoms observed in this patient.

14.
PeerJ ; 11: e16532, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089906

RESUMEN

Coronaviruses have caused widespread disease and death worldwide, leading to the implementation of lockdown measures and the closure of educational institutions in various countries. This research aims to investigate the impact of social isolation on the cognitive functioning of young students. The study included 84 subjects, with 48 being socially isolated and 36 non-isolated individuals. The participants' mental health was assessed using the Mini-Mental State Examination (MMSE), while cognitive functions were evaluated through attention-switching tasks (AST), pattern recognition memory (PRM), and choice reaction time (CRT) tests utilizing the Cambridge Neuropsychological Automated Battery (CANTAB) software. The socially isolated group had an average age of 21.3 ± 1.1 years, whereas the non-isolated group had an average age of 22.8 ± 2.0 years. The MMSE scores were 25.8 ± 1.6 for the socially isolated group and 28.6 ± 1.3 for the non-isolated group. In terms of cognitive functioning, there were significant differences (p = 0.000) observed in the values of AST correct latency for non-switching blocks (blocks 3 and 5) between the socially isolated group (608.1 ± 139.2) and the non-isolated group (499.5 ± 67.8). Similarly, the AST mean correct latency for switching blocks (block 7) was significantly different (p = 0.012) between the socially isolated group (784.4 ± 212.5) and the non-isolated group (671.8 ± 175.6). The socially isolated group exhibited significantly higher values in AST correct mean latency, AST congruent mean latency, AST incongruent mean latency, and AST percent mean correct trials compared to the non-isolated group. Additionally, the PRM mean percent correct significantly differed (p = 0.000) between the isolated group (81.3 ± 12.0) and the non-isolated group (91.9 ± 9.2). The isolated group also showed a higher CRT correct mean latency (482.4 ± 128.9) than the non-isolated group (451.0 ± 59.0), however the difference was not significant. In conclusion, social isolation during the COVID-19 pandemic has resulted in a decline in the cognitive functioning of young students.


Asunto(s)
COVID-19 , Pandemias , Humanos , Adulto Joven , Adulto , Pruebas Neuropsicológicas , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Cognición , Aislamiento Social
15.
PLoS One ; 18(12): e0294663, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38096182

RESUMEN

Hepatitis E virus (HEV) is one of the leading acute liver infections triggered by viral hepatitis. Patients infected with HEV usually recover and the annual death rate is negligible. Currently, there is no HEV licensed vaccine available globally. This study was carried out to design a multi-epitope HEV peptide-based vaccine by retrieving already experimentally validated epitopes from ViPR database leading to epitope prioritization. Epitopes selected as potential vaccine candidates were non-allergen, immunogenic, soluble, non-toxic and IFN gamma positive. The epitopes were linked together by AAY linkers and the linker EAAAK was used to join adjuvant with epitopes. Toll-like receptor (TLR)-4 agonist was used as an adjuvant to boost efficacy of the vaccine. Furthermore, codon optimization followed by disulfide engineering was performed to analyse the designed vaccine's structural stability. Computational modeling of the immune simulation was done to examine the immune response against the vaccine. The designed vaccine construct was docked with TLR-3 receptor for their interactions and then subjected to molecular dynamic simulations. The vaccine model was examined computationally towards the capability of inducing immune responses which showed the induction of both humoral and cell mediated immunity. Taken together, our study suggests an In-silico designed HEV based multi-epitope peptide-based vaccine (MEPV) that needs to be examined in the wet lab-based data that can help to develop a potential vaccine against HEV.


Asunto(s)
Virus de la Hepatitis E , Humanos , Epítopos de Linfocito T , Vacunas de Subunidad , Simulación de Dinámica Molecular , Péptidos , Biología Computacional , Simulación del Acoplamiento Molecular , Epítopos de Linfocito B
16.
Cureus ; 15(11): e48291, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38058330

RESUMEN

INTRODUCTION: Developmental delay (DD) is a neurodevelopmental disorder characterized by delays in multiple domains. The investigation of brain structure in DD has been enhanced by advanced neuroimaging techniques that can identify regional surface deformities. Neuroimaging studies have identified structural brain abnormalities in individuals with DD, but research specific to the Saudi Arabian population is limited. In this study, we examine the neuroanatomical abnormalities in the cortical and subcortical regions of Saudi Arabian children with DD. METHOD: A T1-weighted, 1-mm-thick MRI was used to acquire structural brain images of 29 children with DD and age-matched healthy controls. RESULTS: Analysis of the MRI data revealed significant differences in several cortical and subcortical structures of gray matter (GM) and white matter (WM) in several brain regions of the DD group. Specifically, significant deformities were observed in the caudate nucleus, globus pallidus, frontal gyrus, pars opercularis, pars orbitalis, cingulate gyrus, and subcallosal gyrus. These findings suggest disrupted neurodevelopment in these regions, which may contribute to the cognitive, motor, and behavioral impairments commonly observed in individuals with DD. CONCLUSIONS: The present study provides valuable insights into the neuroanatomical differences in Saudi Arabian children with DD. Our results provide evidence for cortical and subcortical abnormalities in DD. Deformities in the observed regions may contribute to cognitive impairment, emotional dysregulation, mood disorders, and language deficits commonly observed in DD. The structural analysis may enable the identification of neuroanatomical biomarkers to facilitate the early diagnosis or progression of DD. These results suggest that lower cortical complexity in DD children due to alterations in networks may play a critical role in early brain development.

17.
Front Psychiatry ; 14: 1229580, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38111620

RESUMEN

Introduction: Language-based learning disabilities (LBLD) refers to a spectrum of neurodevelopmental-associated disorders that are characterized by cognitive and behavioral differences in comprehending, processing and utilizing spoken and/or written language. The focus of this work was on identifying early predictors of three main specific LBLD including dyslexia, dyscalculia, and dysgraphia. Methods: The Web of Science (WoS) was searched for literature related to (neurocognitive, neurophysiological, and neuroimaging) measurements used to identify early predictors of LBLD from 1991 to 25 October 2021. A retrospective bibliometric analysis was performed to analyze collaboration among countries, institutions, authors, publishing journals, reference co-citation patterns, keyword co-occurrence, keyword clustering, and burst keywords using Biblioanalytics software. Results: In total, 921 publications related to the identification of LBLD using (neurocognitive, neurophysiological, and neuroimaging) modalities were included. The data analysis shows a slow growth in research on the topic in the 90s and early 2000 and growing trend in recent years. The most prolific and cited journal is Neuroimage, followed by Neuropsychologia. The United States and Finland's Universities Jyvaskyla and Helsinki are the leading country and institution in this field, respectively. "Neuroimaging," "brain," "fMRI," "cognitive predictor," "comorbidity," "cortical thickness" were identified as hotspots and trends of (neurocognitive, neurophysiological, and neuroimaging) modalities in the identification of LBLD. Discussion: Early predictors of LBLDs would be useful as targets for specific prevention and intervention programs to be implemented at very young ages, which could have a significant clinical impact. A novel finding of neuroimaging predictors combined with neurocognitive and neuropsychological batteries may have implications for future research.

18.
Saudi Pharm J ; 31(12): 101865, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38028213

RESUMEN

Background: Magnesium and potassium are two critical minerals that have been linked to the treatment of diabetes and its consequences. A lack of magnesium has been linked to insulin resistance and diabetes, whereas potassium has been found to promote insulin sensitivity and glucose metabolism. The study aimed to determine the relationship between cholesterol, liver and kidney markers, and quality of life in diabetic patients before and after magnesium and potassium supplementation. Methods: It was a single-blind randomized controlled study at Lahore Garrison University and Lahore Medical Research Centre (LMRC). The study included 200 diabetes participants. Four groups were made based on supplements. Blood samples of all diabetes patients were obtained to assess their quality of life before and after using Mg + and K + supplements, as well as the association between cholesterol, liver, and kidney markers. Results: The participants' average age was 51.0 ± 11.08. 139 (69.5 %) of the 200 participants were female, whereas 26 (30.5 %) were male. There was no correlation between the quality of life measure and the patients' cholesterol levels before and after the magnesium and potassium supplementation. Furthermore, the kidney and liver indicators were not dependent on the diabetes individuals' cholesterol levels. Conclusions: The study concluded that none of the four groups noticed a significant effect of magnesium and potassium therapies on the patient's quality of life or cholesterol levels. However, more research is needed to determine if liver and kidney problems are linked to cholesterol levels before and after medication, as the current study found no significant correlation between the two parameters.

19.
Cureus ; 15(10): e46874, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37954800

RESUMEN

Systemic lupus erythematosus (SLE) is a chronic, multisystemic autoimmune disease that is diagnosed using specific clinical and biochemical inclusion criteria. Here, we report the case of a young adult who was initially diagnosed with dysphagia and later diagnosed with SLE. Other rheumatological and non-rheumatological conditions were ruled out, and serology revealed that SLE was the cause of the patient's symptoms. To the best of our knowledge, no previous case studies or prior research identify dysphagia as a presenting symptom of SLE. While esophageal dysmotility ranging from ineffective esophageal motility (IEM) to achalasia can manifest as a later clinical consequence of SLE, it is rarely the first symptom of the disease. After diagnosis, the patient was treated with hydroxychloroquine and prednisolone, which led to significant improvement.

20.
Heliyon ; 9(11): e22028, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38034731

RESUMEN

This study was based on the experimental performance evaluation of a wood polymer composite (WPC) that was synthesized by incorporating untreated and treated rice husk (RH) fibers into a polypropylene random copolymer matrix. The submicron-scale RH fibers were alkali-treated to modify the surface and introduce new functional groups in the WPC. A compatibilizer (maleic anhydride) and a thermos-mechanical properties modifier (polypropylene grafted with 30 % glass fiber) were used in the WPC. The effects of untreated and treated RH on the WPC panels were studied using FESEM, FTIR, and microscope images. A pin-on-disk setup was used to investigate the bulk tribological properties of PPRC and WPC. The complex relationship between the friction coefficient of different loading of RH fibers in the WPC, as a function of sliding distance, was analyzed along with the temperature and morphology of the surface. It was observed that untreated RH acted as a friction modifier, while treated RH acted as a solid lubricant. Microhardness was calculated using the QCSM module on nanoindentation. It was found that untreated RH led to an increase in microhardness, while treated RH caused a decrease in hardness compared to PPRC.

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