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1.
Heliyon ; 9(11): e21573, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38058642

RESUMO

The climate, geomorphological changes, and hydrological elements that have occurred have all influenced future flood episodes by increasing the likelihood and intensity of extreme weather occurrences like extreme precipitation events. River bank erosion is a natural geomorphic process that occurs in all channels. As modifications of sizes and channel shapes are made to transport the discharge, sediment abounds from the stream catchment, and floods are triggered dramatically. The aim of this study is to analyze the flood-sensitive regions along the Pahang River Basin and determine how climate and river changes would have an impact on flooding based on hydrometeorological data and information on river characteristics. The study is divided into three stages, namely the upstream, middle stream, and downstream of the Pahang River. The main primary hydrometeorological data and river characteristics, such as Sinuosity Index, Dominant Slope Range and Entrenchment Ratio collected as important inputs in the statistical analysis process. The statistical analyses, namely HACA, PCA, and Linear Regression applied in river classification. The result showed that the middle stream and downstream areas demonstrated the worst flooding affected by anthropogenic and hydrological factors. Rainfall distribution is one of the factors that contributed to the flood disaster. There are strong correlations between the Sinuosity Index (SI) and water level, which indicates that changes occurred at both planform and stream classification. The best management practices towards sustainability are based on the application of the outcomes that have been obtained after the analysis of Pahang River planform changes, Pahang River geometry, and the local rainfall pattern in the Pahang River Basin.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36360843

RESUMO

Forecasting the severity of occupational injuries shall be all industries' top priority. The use of machine learning is theoretically valuable to assist the predictive analysis, thus, this study attempts to propose a feature-optimized predictive model for anticipating occupational injury severity. A public database of 66,405 occupational injury records from OSHA is analyzed using five sets of machine learning models: Support Vector Machine, K-Nearest Neighbors, Naïve Bayes, Decision Tree, and Random Forest. For model comparison, Random Forest outperformed other models with higher accuracy and F1-score. Therefore, it highlighted the potential of ensemble learning as a more accurate prediction model in the field of occupational injury. In constructing the model, this study also proposed the feature optimization technique that revealed the three most important features; 'nature of injury', 'type of event', and 'affected body part' in developing model. The accuracy of the Random Forest model was improved by 0.5% or 0.895 and 0.954 for the prediction of hospitalization and amputation, respectively by redeveloping and optimizing the model with hyperparameter tuning. The feature optimization is essential in providing insight knowledge to the Safety and Health Practitioners for future injury corrective and preventive strategies. This study has shown promising potential for smart workplace surveillance.


Assuntos
Traumatismos Ocupacionais , Humanos , Traumatismos Ocupacionais/epidemiologia , Traumatismos Ocupacionais/prevenção & controle , Teorema de Bayes , Algoritmos , Local de Trabalho , Aprendizado de Máquina , Máquina de Vetores de Suporte
3.
Ecotoxicol Environ Saf ; 221: 112430, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34147866

RESUMO

The exposure of school children to indoor air pollutants has increased allergy and respiratory diseases. The objective of this study were to determine the toxicodynamic interaction of indoor pollutants exposure, biological and chemical with expression of adhesion molecules on eosinophil and neutrophil. A self-administered questionnaire, allergy skin test, and fractional exhaled nitric oxide (FeNO) analyser were used to collect information on health status, sensitization to allergens and respiratory inflammation, respectively among school children at age of 14 years. The sputum induced were analysed to determine the expression of CD11b, CD35, CD63 and CD66b on eosinophil and neutrophil by using flow cytometry technique. The particulate matter (PM2.5 and PM10), NO2, CO2, and formaldehyde, temperature, and relative humidity were measured inside the classrooms. The fungal DNA were extracted from settled dust collected from classrooms and evaluated using metagenomic techniques. We applied chemometric and regression in statistical analysis. A total of 1869 unique of operational taxonomic units (OTUs) of fungi were identified with dominated at genus level by Aspergillus (15.8%), Verrucoconiothyrium (5.5%), and Ganoderma (4.6%). Chemometric and regression results revealed that relative abundance of T. asahii were associated with down regulation of CD66b expressed on eosinophil, and elevation of FeNO levels in predicting asthmatic children with model accuracy of 63.6%. Meanwhile, upregulation of CD11b expressed on eosinophil were associated with relative abundance of A. clavatus and regulated by PM2.5. There were significant association of P. bandonii with upregulation of CD63 expressed on neutrophil and exposure to NO2. Our findings indicate that exposure to PM2.5, NO2, T. asahii, P.bandonii and A.clavatus are likely interrelated with upregulation of activation and degranulation markers on both eosinophil and neutrophil.


Assuntos
Poeira , Fungos/genética , Hipersensibilidade/microbiologia , Metagenoma , Pneumonia/microbiologia , Adolescente , Poluição do Ar em Ambientes Fechados/análise , Asma , Fungos/metabolismo , Humanos , Masculino , Material Particulado/análise , Escarro
4.
J Med Signals Sens ; 10(2): 105-112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32676446

RESUMO

BACKGROUND: For a new biomaterial which is going to be applied in bone tissue regeneration, bioactivity (bone bonding ability) and desirable mechanical properties are very essential parameters to take into consideration. In the present study, the gehlenite's mechanical properties and bioactivity are assessed and compared with hydroxyapatite (HA) for bone tissue regeneration. METHOD: Gehlenite and HA nanoparticles are synthesized through sol-gel method and coprecipitation technique, respectively, and their physical and chemical properties are characterized through X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. RESULTS: The results prove that the gehlenite and HA phases without any undesirable phase are obtained, and the particles of both compounds are in the nanometer range with spherical morphology. The compressive strength of both compounds are assessed, and the values for gehlenite and HA disks are 144 ± 5 and 150 ± 4.8 MPa, respectively. Next, their bioactivity potential is assessed into simulated body fluid (SBF) up to 21 days, and the results show that after 14 days, gehlenite disk's surface is completely covered with newly formed Ca-P particles. However, some sporadic precipitations after 21 days soaking into SBF are formed onto the HA disk's surface. CONCLUSION: This comparative study shows that nanostructured gehlenite disk with desirable mechanical properties and faster bioactivity kinetic than HA can be considered as a promising bioceramic for bone tissue regeneration.

5.
Int J Biol Macromol ; 159: 154-173, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32416294

RESUMO

Lignin displays attractive properties in peripheral nerve applications. Here, aligned polycaprolactone (PCL) fibers with various percentages of lignin nanoparticles were fabricated using the electrospinning method. The morphologies, contact angles, mechanical properties, in vitro degradation, and water uptake of the PCL/lignin fibers were characterized. Cell viability and adhesion of PC12 and human adipose-derived stem cells (hADSCs) were studied employing MTT assay and SEM, respectively. SEM, immunocytochemistry, and Real-Time PCR were utilized to characterize neural differentiation and neurite length of PC12 and hADSCs. To further study on lignin effect on nerve regeneration, in vivo studies were performed. The results indicated that all nanocomposite fibers were smooth and bead-free. With increasing the lignin content, the water contact angle decreased while in vitro degradation, water uptake, and Young's modulus increased compared to the PCL fibers. Cell viability, and differentiation along with neurite length extension were promoted by increasing lignin content. The neural markers expression for differentiated cells were upregulated by the increase of lignin percent. In vivo investigation also demonstrates that sample groups incorporating 15% lignin nanoparticles showed better regeneration among others. Therefore, PCL with 15% of lignin nanoparticles shows great potential to be applied for nerve regeneration.


Assuntos
Lignina/química , Nanopartículas/química , Regeneração Nervosa , Poliésteres/química , Adulto , Animais , Células Cultivadas , Módulo de Elasticidade , Humanos , Masculino , Nanopartículas/uso terapêutico , Crescimento Neuronal , Células PC12 , Traumatismos dos Nervos Periféricos/terapia , Ratos , Ratos Wistar
6.
Mater Sci Eng C Mater Biol Appl ; 109: 110579, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228948

RESUMO

3D multifunctional bone scaffolds have recently attracted more attention in bone tissue engineering because of addressing critical issues like bone cancer and inflammation beside bone regeneration. In this study, a 3D bone scaffold is fabricated from Mg2SiO4-CoFe2O4 nanocomposite which is synthesized via a two-step synthesis strategy and then the scaffold's surface is modified with poly-3-hydroxybutyrate (P3HB)-ordered mesoporous magnesium silicate (OMMS) composite to improve its physicochemical and biological properties. The Mg2SiO4-CoFe2O4 scaffold is fabricated through polymer sponge technique and the scaffold exhibits an interconnected porous structure in the range of 100-600 µm. The scaffold is then coated with OMMS/P3HB composite via dip coating and the physical, chemical, and biological-related properties of OMMS/P3HB composite-coated scaffold are assessed and compared to the non-coated and P3HB-coated scaffolds in vitro. It is found that, on the one hand, P3HB increases the cell attachment, proliferation, and compressive strength of the scaffold, but on the other hand, it weakens the bioactivity kinetic. Addition of OMMS to the coating composition is accompanied with significant increase in bioactivity kinetic. Besides, OMMS/P3HB composite-coated scaffold exhibits higher drug loading capacity and more controlled release manner up to 240 h than the other samples because of OMMS which has a high surface area and ordered mesoporous structure suitable for controlled release applications. The overall results indicate that OMMS/P3HB coating on Mg2SiO4-CoFe2O4 scaffold leads to a great improvement in bioactivity, drug delivery potential, compressive strength, cell viability, and proliferation. Moreover, OMMS/P3HB composite-coated scaffold has heat generation capability for hyperthermia-based bone cancer therapy and so it is suggested as a multifunctional scaffold with great potentials for bone cancer therapy and regeneration.


Assuntos
Neoplasias Ósseas/terapia , Regeneração Óssea , Materiais Revestidos Biocompatíveis , Hipertermia Induzida , Nanocompostos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacocinética , Materiais Revestidos Biocompatíveis/farmacologia , Cobalto/química , Cobalto/farmacocinética , Cobalto/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacocinética , Compostos Férricos/farmacologia , Humanos , Hidroxibutiratos , Silicatos de Magnésio/química , Silicatos de Magnésio/farmacocinética , Silicatos de Magnésio/farmacologia , Nanocompostos/química , Nanocompostos/uso terapêutico , Poliésteres , Porosidade
7.
Heliyon ; 5(10): e02534, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31667387

RESUMO

There has been a growing concern on the rising of environmental issues in Malaysia over the last decade. Many environmental studies conducted in this country began to utilise the chemometrics techniques to overcome the limitation in the environmental monitoring studies. Chemometrics becomes an important tool in environmental fields to evaluate the relationship of various environmental variables particularly in a large and complex database. The review aimed to analyse and summarize the current evidences and limitations on the application of chemometrics techniques in the environmental studies in Malaysia. The study performed a comprehensive review of relevant scientific journals concerning on the major environmental issues in the country, published between 2013 and 2017. A total of 29 papers which focused on the environmental issues were reviewed. Available evidences suggested that chemometrics techniques have a greater accuracy, flexibility and efficiency to be applied in environmental modelling. It also reported that chemometrics techniques are more practical for cost effective and time management in sampling and monitoring purposes. However, chemometrics is relatively new in environmental field in Malaysia and various scopes need to be considered in the future as the current studies focused on very limited number of major environmental issues. Overall, chemometrics techniques have a lot of advantages in solving environmental problems. The development of chemometrics in environmental studies in the country is necessary to advance understanding, thus able to produce more significant impacts towards the effective environmental management.

8.
Mater Sci Eng C Mater Biol Appl ; 104: 110005, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499996

RESUMO

Electrospinning of natural and synthetic polymers open a new practical approach to tissue engineering by producing fibers. In this study, aligned electrospun poly(vinyl alcohol) (PVA)-poly(glycerol sebacate) (PGS) fibers with various percentages of lignin (0, 1, 3, and 5%wt) fabricated for nerve tissue engineering. The effect of the different amount of lignin on the morphology and diameter of the fibers was investigated by scanning electron microscopy (SEM). The physicochemical properties of fibers were studied using FTIR, tensile strain, contact angle, water uptake, and degradation test. MTT assay and SEM were employed to evaluate PC12 cell proliferation and adhesion, respectively. Immunocytochemistry and gene expression were utilized to study how the lignin affected on cell differentiation. The results revealed the smooth with a uniform diameter of the fabricated fibers, and the increased amount of lignin reduced the fiber diameter from 530 to 370 nm. The modulus of elasticity increased from 0.1 to 0.4 MPa by increasing the lignin percentage. The PC12 cell culture indicated that the lignin enhanced cell proliferation. The mRNA expression level for Gfap, ß-Tub III, and Map2 and immunocytochemistry (Map2) revealed the positive effect of lignin on neural cell differentiation. Finally, the results suggest PVA-PGS/5% lignin as a promising material for nerve tissue engineering.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Decanoatos/química , Glicerol/análogos & derivados , Lignina/química , Nanofibras/administração & dosagem , Nanofibras/química , Tecido Nervoso/efeitos dos fármacos , Polímeros/química , Álcool de Polivinil/química , Animais , Linhagem Celular Tumoral , Elasticidade/efeitos dos fármacos , Glicerol/química , Células PC12 , Ratos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
9.
Mater Sci Eng C Mater Biol Appl ; 96: 765-775, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606589

RESUMO

Infection is quite usual for implants after surgery and a systemic administration of antibiotics causes problems before the eradication of bacteria. Localized drug delivery from implants is an effective way by which the mentioned target can be met. In the current work, ordered mesoporous magnesium silicate (OMMS) is coated on plasma electrolytic oxidation (PEO)-modified titanium (Ti) substrate through electrophoretic deposition (EPD) and rifampin as an antibiotic is loaded on OMMS coating to be applied as an antibacterial coating. The immersion test into simulated body fluid and also potentiodynamic polarization assay are adopted to assess the in vitro bioactivity up to 7 days and corrosion resistance of the specimens, respectively. The double surface coatings of PEO and EPD are achieved on Ti substrate and the thickness for each one is found to be 4 and 25 µm, respectively. Regarding to drug delivery capability of OMMS as the EPD coating, the loading capacity is 25% and release trend sustains up to 96 h. The antibacterial activity and also cell viability of OMMS coating are significantly increased with rifampin loading. The results of our study exhibit that OMMS as a multifunctional coating deposited on the PEO-modified Ti substrate improves corrosion resistance, in vitro bioactivity, alkaline phosphatase activity, and mineralization of the substrate. Moreover, rifampin-loaded OMMS coating is not only able to prevent infection, but it also increases the osteogenesis cells viability. Therefore, rifampin-loaded OMMS coating on Ti is potentially regarded appropriate for orthopedic applications.


Assuntos
Materiais Revestidos Biocompatíveis , Implantes Experimentais , Silicatos de Magnésio , Nanoporos , Titânio , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacocinética , Materiais Revestidos Biocompatíveis/farmacologia , Eletroforese , Humanos , Silicatos de Magnésio/química , Silicatos de Magnésio/farmacocinética , Silicatos de Magnésio/farmacologia , Titânio/química , Titânio/farmacocinética , Titânio/farmacologia
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