17 research outputs found

    Oil palm leaf fibre and its suitability for paper-based products

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    Due to the shortage of wood as origin materials for paper-based production, agro-residue materials have been explored in the quest of finding the best alternative fibre. Oil palm leaf (OPL) is one of agro-residue that has potential due to its comparable characteristics with wood fibre. Studies on chemical compositions, fibre morphology, and mechanical property of OPL have been carried out aiming to evaluate its potential as a substitute raw material for pulp and paper-based production. The chemical compositions were analysed according to the TAPPI standard, Kurscher-Hoffner and chlorite methods accordingly. The mechanical property (tensile, tearing and bursting strengths) were determined as described in TAPPI test methods. Fibre dimensions were determined using Franklin method and analysed under the optical microscope. The content of cellulose in the OPL is determined to be 43.8%. Although, this result is lower than wood fibre (53%), OPL has higher hemicellulose content (36.4%) than the wood fibre (27.5%). In addition, the lignin content (19.7%) of OPL is in the low range of those in wood resources (18 - 25%). These parameters are important components to produce good quality pulp and will provide high mechanical strength of the paper-based products. The measured fibre length of oil palm leaf (1.13 mm) is shorter than the wood fibre (1.90 mm). Meanwhile, the mechanical property of OPL showed lower indexes than wood resources, however, tear (1.80 mN.m2/g) and burst (0.95 kPa.m2/g) indexes of OPL are higher than other published and successful wood resources (Eucalyptus). Based on the analyses, the oil palm leaf is indeed a suitable alternative of raw material for pulp and paper-based industries

    Morphological characteristics of black aspergilli isolated from clinical wastes

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    The present study aimed to recognize the microscopic characteristics of black aspergilli species which exhibit similar characteristics on culture media. Forty eight black aspergilli isolates were obtained from clinical wastes and purified using single spore technique on six different culture media. The ultrastructure of fungal conidiophore and spores was detected by using Scanning Electron Microscope (SEM). The fungal isolates were identified within five species included A. niger, A. tubingensis, Aspergillus section Nigri, A. violaceofuscus, A. neoniger. Besides, two isolates identified as Aspergillus sp. strain no. 39, Aspergillus sp. strain no. 53 appear as new strains based on the structure of conidiophore and spores. The fungi species have similar culture characteristics. However, SEM observation demonstrated that they have quite different conidiophore and spores morphology. The study revealed that the microstructure of the fungal spores and conidiophores plays an important role in the identification of fungi species based on the phenotypic method

    CFD Simulation Analysis of Non-Premixed Combustion using a Novel AxialRadial Combined Swirler for Emission Reduction Enhancement

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    Combustion industries for many decades dealing with the issues in reducing the emissions without affecting the performance of combustion. The present study aims to investigate the performance of swirler mechanism which combining between both axial and radial types to reduce emissions and increase the mixing process via the nonpremixed method. Each of axial and radial swirler consisted with 8 blades vane. Swirl angle for radial swirler is 35° and inclination angle for axial swirler is 15°. The swirler is designed using Solidworks software package and CFD analysis was then performed using ANSYS Fluent software package. The fuel used is liquefied petroleum gas (LPG) gas which contained 30% propane and 70% butane. The turbulence model standard kepsilon was used in this study. The result found that the combined swirler was capable to reduce CO emission as the complete reaction into CO2 component was higher. This is due to the broader region of temperature and higher velocity magnitude produced by the combined swirler. However, the maximum temperature result for axial swirler was higher than the combined swirler. As a recommendation, the inclination blade angle in the axial swirler of the combined swirler should be increased to increase the temperature value

    Reduction of bacteria in storage system of sewage effluents

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    The present work is aimed to investigate the linear regression model of total coliform (TC), faecal coli-form (FC) and enterococci (ENT) responses in the storage system of sewage effluents at different temperatures (room temperature 25 ± 2 °C, 55 and 65 °C). Five litres (v/v) of sewage effluent samples was stored at room temperature (25 ± 2 °C) for 1, 2, 3 and 4 weeks. In order to investigate the response of bacteria to the storage system at thermal conditions, the sewage samples were stored at the tempera-tures of 55 and 65 °C in a water bath shaker for 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 min, respectively. The results indicated that the storage system at room tem-perature significantly (p < 0.01) effected the reduction of TC (33%), FC (36.6%) and ENT (47.8%). Moreover, sew-age effluent met WHO guidelines after two weeks of stor-age period at room temperature. The storage system at 55 and 65 °C had more significant influence (p < 0.01) on TC, FC and ENT. The reductions for TC, FC and ENT were 49.6 versus 64, 47.7 versus 83.2% and 47.4 versus 57.3%, respectively. ENT (Gram-positive bacteria) exhibited more resistance to the storage system at 65 °C than TC and FC (both are Gram-negative bacteria). This might be due to the differences in the cell wall structure. It can be concluded that the storage system of sewage effluents has a significant potential for the reduction of indicator bacteria

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

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    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

    Removal of pathogenic bacteria from sewage-treated effluent and biosolids for agricultural purposes

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    Abstract The reuse of treated sewage for irrigation is considered as an important alternative water source in the new water management strategy of the countries that face a severe deficiency of water resources such as the Middle East countries. The organic material and fertilizing elements contained in biosolids are essential for maintaining soil fertility. However, both treated sewage and biosolids contain a large diversity of pathogens that would be transmitted to the environment and infect human directly or indirectly. Therefore, those pathogens should be reduced from the treated sewage and biosolids before the reuse in the agriculture. This paper reviews the considerations for reuse of treated sewage and biosolids in agriculture and further treatments used for reduction of pathogenic bacteria. The treatment methods used for the reduction of pathogens in these wastes have reviewed. It appeared that the main concern associated with the reduction of pathogenic bacteria lies in their ability to regrow in the treated sewage and biosolids. Therefore, the effective treatment method is that it has the potential to destruct pathogens cells and remove the nutrients to prevent the regrowth or recontamination from the surrounded environment. The removal of nutrients might be applicable in the sewage but not in the biosolids due to high nutrient contents. However, the reduction of health risk in the biosolids might be carried out by regulating the biosolid utilization and selecting the plant species grown in the fertilized soil with biosolids
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