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1.
J Clin Pharm Ther ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565097

RESUMO

WHAT IS KNOWN AND OBJECTIVE: There is limited data on the specific risks of anaphylaxis induced by beta-lactam drugs. The aim of this study was to compare the risks of reporting beta-lactam-induced anaphylaxis using the national pharmacovigilance database of Vietnam (NPDV). METHODS: The multivariate generalised linear regression model was applied for signal generation and comparison of beta-lactams. RESULTS: Between 2010 and 2016, there were 2,921 reports of anaphylaxis (19.93%) from 14,655 spontaneous reports of beta-lactam use in the NDPV. Anaphylaxis signal generation was also found for the subgroup J01D (cephalosporins and carbapenems) (ROR = 1.27 [1.16-1.39]) and beta-lactamase-sensitive penicillins (ROR = 1.74 [1.27-2.35]). In the third generation cephalosporin subgroup, different risks were identified for the following combinations of beta-lactams: 1) cefotaxime with cefoperazone+sulbactam; 2) cefixime/cefpodoxime/cefdinir with cefoperazone+sulbactam or ceftizoxime/cefoperazone/ceftazidime/ceftriaxone/cefotaxime. For the second generation cephalosporin subgroup, different risks were found for cefotiam compared to cefmetazole, cefaclor, cefamandole and cefuroxime. WHAT IS NEW AND CONCLUSION: These findings identified and highlighted the different anaphylactic risks caused by various beta-lactams in the main subgroups.

2.
World Neurosurg ; 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33601082

RESUMO

OBJECTIVES: Fluorescence-guided surgery (FGS) may improve completeness of resection in transsphenoidal surgery for Cushing's Disease (CD) by enabling visualization of residual tumor tissue at the margins. In this review we discuss somatostatin receptors (SSTRs) as targets for FGS and overview existing SSTR-specific imaging agents. We also compare SSTR expression in normal pituitary and corticotrophinoma tissues from human and canine CD patients to assess canines as a translational model for CD. METHODS: A PubMed literature search was conducted for publications containing the terms canine, somatostatin receptor, Cushing's Disease, and corticotroph adenoma. SSTR expression data from each study was documented as the presence or absence of expression, or when possible, the number of tumors expressing a given SSTR subtype within a group of tumors being studied. Studies that used RT-PCR to quantify SSTR expression were selected for additional comparative analysis. RESULTS: SSTR5 is strongly expressed in human corticotroph adenomas and weakly expressed in surrounding pituitary parenchyma, a pattern not conclusively observed in canine patients. SSTR2 mRNA expression is similar in human normal pituitary and corticotrophinoma cells, but may be significantly higher in canine normal pituitary tissue than in corticotroph tumoral tissue. Limited data was available on SSTR subtypes 1, 3, and 4. CONCLUSIONS: Further studies must fill the knowledge gaps related to species-specific SSTR expression, thus using canine CD as a translational model may be premature. We do conclude that the expression profile of SSTR5 (i.e. high local expression in pituitary adenomas relative to normal surrounding tissues) makes SSTR5 a promising molecular target for FGS.

3.
Int J Med Sci ; 18(6): 1406-1414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628097

RESUMO

Enolase (ENO) 1 is a key glycolytic enzyme and important player in tumorigenesis. ENO1 overexpression has been correlated with tumor progression and/or worse prognosis in several solid malignancies. However, data concerning the impact of ENO1 in cancer conflict. The study correlated local and circulating ENO1 protein levels in esophageal cancer (EC) with clinicopathological data, to assess its potential clinical value. ENO1 expression was analyzed by immunohistochemistry in paired tumor and non-tumor tissue samples from 40 EC cases and mucosal biopsies from 45 Barrett's esophagus (BE) cases, plus in plasma from these patients and 25 matched healthy controls. ENO1 was abnormally elevated in cancer-cell cytoplasm in both EC types, in esophageal squamous cell carcinoma and in adenocarcinoma (EAC), increasing significantly with tumor stage progression and the transition from BE to EAC. EAC patients exhibited significantly lower ENO1 plasma concentrations than normal subjects. Neither local nor systemic ENO1 expression levels were significantly associated with overall survival. These results indicate ENO1 as potential biomarker, delineating a population of patients with Barrett's esophagus at high risk of cancer, and as new therapeutic opportunity in EC patient management. However, further confirmation might be necessary.

4.
Biom J ; 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33464615

RESUMO

We are concerned with testing replicability hypotheses for many endpoints simultaneously. This constitutes a multiple test problem with composite null hypotheses. Traditional p -values, which are computed under least favorable parameter configurations (LFCs), are over-conservative in the case of composite null hypotheses. As demonstrated in prior work, this poses severe challenges in the multiple testing context, especially when one goal of the statistical analysis is to estimate the proportion π 0 of true null hypotheses. Randomized p -values have been proposed to remedy this issue. In the present work, we discuss the application of randomized p -values in replicability analysis. In particular, we introduce a general class of statistical models for which valid, randomized p -values can be calculated easily. By means of computer simulations, we demonstrate that their usage typically leads to a much more accurate estimation of π 0 than the LFC-based approach. Finally, we apply our proposed methodology to a real data example from genomics.

5.
Nanoscale ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33410829

RESUMO

For the last decade, two-dimensional transition metal dichalcogenides (TMDCs) have attracted considerable attention due to their unique physical and chemical properties. Novel devices based on these materials are commonly fabricated using the exfoliated samples, which lacks control of the thickness and cannot be scaled. Therefore, the synthesis of large-area TMDC thin films with a high uniformity to advance the field is required. This article reviews the latest advances in the synthesis of wafer-scale thin films using chemical vapor deposition methods. The key factors that determine the electrical performance of TMDCs are introduced, including the interfacial properties and defects. The latest solution-based techniques which suggest the opportunity to obtain large-area TMDC thin films with a low-cost process and the potential applications in electronics and optoelectronics are also discussed. The outlook for future research directions, challenges, and possible development of 2D materials are further discussed.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33415834

RESUMO

Insulin resistance (IR), a metabolic risk factor, is linked to the pathogenetic mechanism of primary hypertension. Detecting IR in the patients with hypertension will help to predict and stratify the added cardiovascular risk, institute appropriate IR management, and manage hypertension optimally. There are many methods for assessing IR, each with distinct advantages and disadvantages. The euglycemic insulin clamp and intravenous glucose tolerance test, gold standards for measuring IR, are used in research but not in clinical practice. Homeostatic model assessment (HOMA-IR), a method for assessing ß-cell function and IR, is frequently applied presently, particularly in Asia. Besides, the triglyceride-glucose index (TyG) first published by South American authors showed a good correlation with the insulin clamp technique and HOMA-IR index. This simple, convenient, and low-cost TyG index is of research interest in many countries in Asia and can be used to screen for IR in the Asian hypertensive community.

7.
Sci Rep ; 11(1): 792, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436988

RESUMO

Biomass, one of the renewable resources, is expected to play an important role in the world's energy future. In Asia, rice straw is an abundant agricultural surplus because rice is one of the leading staple food crops in the region. Often, rice straw is burned directly in the field via uncontrolled combustion methods that emit large amounts of short-lived air pollutants, greenhouse gases, and other pollutants. In Vietnam, the energy and environment protection sectors are facing great challenges because of rapid urbanisation and industrialisation. A national strategic choice is to exploit renewable energy, including biomass-derived energy, to achieve energy security and CO2 emission reduction. This study investigates the potential of rice straw as an energy source for power plants at a local scale in Vietnam using data derived from satellite Sentinel-1 images. The results show that Vietnam can produce 2,565 MW from rice straw, for which 24 out of 63 provinces have a potential capacity higher than 30 MW, and the Kien Giang province has the highest capacity (245 MW). The study also analyses limitations and obstacles overcoming which can promote the biomass energy sector in the country.

8.
Sci Total Environ ; 770: 144672, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33513507

RESUMO

Monitoring data on organic pollutants published between the late 1960s and 2020 are reviewed to provide comprehensive and updated insights into their bioaccumulation characteristics, sources, and fate in snakes. Multiple organic pollutant classes including pesticides, polychlorinated biphenyls, chlorinated paraffins, dioxin-related compounds, alkanes, polycyclic aromatic hydrocarbons, flame retardants, plasticizers, etc., were detected in various aquatic and terrestrial snake species with concentrations and patterns varying between species and locations. In general, higher concentrations of organic pollutants were found in snakes collected from contaminated sites (e.g., densely populated, pesticide-treated, and waste processing areas), suggesting that snakes can serve as good biomonitors of environmental pollution caused by organic contaminants. Factors influencing concentrations and patterns of organic pollutants in snakes are discussed, providing an overview of current understanding about their accumulation, transformation, and elimination processes. Potential negative effects associated with organic pollutants in snakes and their predators are also considered. Based on such discussions, research gaps and future perspectives on the utilization of snake biomonitoring studies are addressed, heading towards an effective monitoring and assessment scheme for a variety of legacy and emerging organic pollutants in the environment.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33290724

RESUMO

PURPOSE: Atherosclerotic plaques develop as a result of a low-grade, chronic, systemic inflammatory response to the injury of endothelial cells arising from lipid deposition within the intima. Increased white blood cell count (WBCC) is both a validated "biologic marker" of the extent of this inflammatory process and a key participant in the development of subsequent atherosclerotic ischemic heart disease manifesting as myocardial infarction. We sought to determine if calcified carotid artery plaque (CCAP) on a panoramic image (PI), also a validated risk indicator of future myocardial infarction, is associated with increased WBCC. PATIENTS AND METHODS: We retrospectively evaluated the PI and medical records of white male military veterans aged 55 years and older treated by a VA dental service. Established were 2 cohorts of patients, 50 having plaques (CCAP+) and 50 without plaques (CCAP-). Predictor variable was CCAP+; outcome variable was WBCC. Bootstrapping analysis determined the differences in mean WBCCs between groups. Statistical significance set at ≤ 0.05. RESULTS: The study group, (mean age 74; range 59 to 91 years) demonstrated a mean WBCC of 8,062 per mm3. The control group, (mean age 72 range; 57 to 94) evidenced a mean WBCC of 7,058 per mm3. Bootstrapping analysis of WBCC values demonstrated a significant (P = .012) difference (95% confidence interval of difference of mean, -806, 742; observed effect size, 1004) between groups. CONCLUSIONS: The presence of CCAP demonstrated on PIs of older Caucasian men is associated with elevated WBCC. Concomitant presence of CCAP on PI and increased WBCC (≥7,800 per mm3) amplifies need for medical consultation before intravenous anesthesia and maxillofacial surgical procedures.

10.
Data Brief ; 33: 106525, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33294521

RESUMO

In every educational system, teacher development has a vital role in its sector and the health of the social, cultural, and economic sectors. For this redeeming feature, all stakeholders such as education policymakers, school superintendents, and school faculties make a big room for teachers' improvement throughout continuous professional development (CPD) provisions. However, to embark on a new educational adventure is a challenging target to meet, especially when the teacher frames their teaching and learning concept years after years. We decided to survey Vietnamese teachers' habits and motivation to trace their origin back to teachers' partaking reason in these programs. This dataset acquisition occurred from 24 Sep 2019 to 26 Mar 2020 and approached public and private schools (using traditional, bi-lingual, or international curriculum). Overall, the dataset includes 464 observations (263 Vietnamese teachers and 202 expatriate teachers) from 48 K-12 schools across Vietnam. The researchers divided this dataset into three main sections, including (i) The demographic information; (ii) Teacher's CPD habits; and (iii) Teacher's perceptions concerning Project-based and Problem-based Learning (PBL).

11.
Fetal Pediatr Pathol ; : 1-11, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33295826

RESUMO

INTRODUCTION: VE1 is a monoclonal antibody detecting mutant BRAF V600E protein by immunohistochemistry (IHC) with a high concordance rate with molecular analysis in many cancers. Materials and methods: BRAF V600E mutation was assessed on 94 pediatric LCH patients using sequencing analysis and VE1 immunohistochemistry with stringent and lenient-scoring criteria. Results: BRAF V600E mutation exon 15 was detected by sequencing in 47.9% of LCH cases. BRAF V600E mutation rate in multiple-system LCH was 65.2%, significantly higher than in single-system LCH (p = .001). VE1 assays showed 35.6% sensitivity, 75.5% specificity (Stringent criteria), and 91.1% sensitivity, 35.7% specificity (Lenient criteria). Conclusions: The proportion of BRAF V600E mutational status was relatively high and related to high-risk LCH. Molecular assays for BRAF mutation detection are preferred in LCH lesions. VE1 is not ready as an alternative option for LCH BRAF testing.

12.
Chemosphere ; : 129092, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33303230

RESUMO

There is growing concern regarding human dietary exposure to arsenic (As) via consumption of rice. The concentration and speciation of As in rice are highly variable, and models describing rice As speciation as a function of environmental covariates remain elusive. We conducted a survey of paddy rice and soil in the Mekong Delta with the objective of linking patterns in rice As content to soil chemical variables or hydrogeological parameters. The sum of As species (ΣAs) in husked rice averaged 243 µg/kg and the average inorganic As (iAs) content was 84%. There was no relationship found between rice As concentration or speciation and As levels in soil. However, mean As concentrations in groundwater near rice sampling locations were strongly correlated with grain ΣAs and iAs over a large part of the study region, despite the fact that groundwater is not commonly used for rice paddy irrigation in this region. We hypothesize that surficial sediments with high concentrations of soluble and plant-available As also serve as sources of arsenic to downgradient shallow aquifers, explaining the observed associations between rice and groundwater As. This study suggests that shallow groundwater As concentrations may serve as a useful indicator for locations at risk of elevated iAs concentrations in rice.

13.
Chemosphere ; 266: 129180, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33307412

RESUMO

Contamination levels and temporal trends of polybrominated diphenyl ethers (PBDEs) and some alternative brominated flame retardants (BFRs) were examined in a dated sediment core from the deepest part of the Beppu Bay, southwestern Japan. PBDEs were found in the upper layers of 0-15 cm depth at concentrations ranging from 5200 to 32,600 pg g-1 with the peak estimated at 1995. Decabromodiphenyl ether (BDE-209) was the most abundant congener, accounting for 96% in average of total PBDEs. The vertical profile of BDE-209 observed in our sediment core generally agreed with the historical pattern of domestic demand of commercial deca-BDE mixtures in Japan, and perfectly matched with maximum stock of these products (i.e., 42,000 tons in 1995). Among alternative BFRs, only decabromodiphenyl ethane (DBDPE), a replacement of deca-BDE, was found at significant levels with concentrations of 69-850 pg g-1 in sediment layers dated between 1991 and 2011. Ratios of DBDPE to BDE-209 gradually increased during this period, implying opposite trends of these two compounds and the role of DBDPE as a deca-BDE's alternative. The occurrence of deca-BDE components in sediments may pose medium risk to benthic aquatic life, while the ecological risk of other PBDE homologs and DBDPE was negligible.

14.
Nat Prod Res ; : 1-8, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33350349

RESUMO

Reinvestigation of a methanol extract of Uraria crinita afforded a new 3- hydroxyisoflavanone, 3,5,7,2',4'-pentahydroxyisoflavanone (1), two new monoaryl glucosides, 3,4-dimethoxyphenyl 1-O-(6'-O-acetyl)-ß-D-glucopyranoside (2) and 3,4,5-trimethoxyphenyl 1-O-(6'-O-acetyl)-ß-D-glucopyranoside (3), in addition to three known compounds, 3'-O-methylorobol (4), robusflavone B (5), and apigenin (6). The structural elucidation of these compounds was achieved by analyses of their spectroscopic data (HR-ESI-MS, 1 D- and 2 D-NMR) and acidic hydrolysis. The U. crinita extracts and compounds 1-6 exhibited weak or no cytotoxic activity against KB, HepG2, Lu and MCF7 cell lines.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33230799

RESUMO

Currently, the considerable decline in fossil fuel resources and the high rise in vehicle emissions have prompted researchers and governments to formulate strategies for sustainable energy development. In addition to imposing strict laws, promoting sustainable energy sources such as the development of new types of non-fossil fuels has been considered a suitable direction for the roadmap to healing the Earth's environment. Biomass sources have affirmed huge potentials in the production of biofuels. In the pathway of searching renewable biofuels, it is found that that 2,5-dimethylfuran (DMF) can become a promising fuel because it is synthesized from lignocellulose biomass, which is an available feedstock for the production of prospective fuels. Indeed, recent review studies have focused in great detail on engine performance evaluation using DMF but seemed to have gaps in emission characteristics. In this work, the controversial issues of emissions from spark and compression ignition engines during the DMF combustion were completely assessed. Indeed, the mechanism of formation and oxidation of DMF compounds during combustion was clearly described to serve as the basis for analyzing and comparing the pollution emission behavior of different fuels. More importantly, gaseous emissions, PM characteristics, and soot tendency from spark and compression ignition engines were thoroughly evaluated on the basis of the experimental and numerical data. In general, DMF has shown outstanding advantages upon emissions compared to fossil fuels; however, the impacts of DMF on the engine durability and fuel system should be further investigated to have a comprehensive analysis of this biofuel class.

16.
Nanoscale ; 12(46): 23721-23731, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33231239

RESUMO

Solid-state nanopore (SSN)-based analytical methods have found abundant use in genomics and proteomics with fledgling contributions to virology - a clinically critical field with emphasis on both infectious and designer-drug carriers. Here we demonstrate the ability of SSN to successfully discriminate adeno-associated viruses (AAVs) based on their genetic cargo [double-stranded DNA (AAVdsDNA), single-stranded DNA (AAVssDNA) or none (AAVempty)], devoid of digestion steps, through nanopore-induced electro-deformation (characterized by relative current change; ΔI/I0). The deformation order was found to be AAVempty > AAVssDNA > AAVdsDNA. A deep learning algorithm was developed by integrating support vector machine with an existing neural network, which successfully classified AAVs from SSN resistive-pulses (characteristic of genetic cargo) with >95% accuracy - a potential tool for clinical and biomedical applications. Subsequently, the presence of AAVempty in spiked AAVdsDNA was flagged using the ΔI/I0 distribution characteristics of the two types for mixtures composed of ∼75 : 25% and ∼40 : 60% (in concentration) AAVempty : AAVdsDNA.

17.
Sci Total Environ ; : 143274, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33183808

RESUMO

The occurrence of seven typical parabens was investigated in several types of personal care products (PCPs) sold at supermarkets and in indoor dust samples collected from houses, laboratories, and medical stores in Hanoi, Vietnam. Parabens were frequently detected in PCPs regardless of the paraben indication in their ingredient labels. However, concentrations of parabens in labeled products (median 3280; range 1370-5610 µg/g) were much higher than those found in non-labeled products (69.4; not detected - 356 µg/g). Parabens were also measured in indoor dust samples of this study at elevated concentrations, ranging from not detected to 1650 (median 286 ng/g). Levels of parabens in the indoor dust samples collected in 2019 decreased in the order: house > medical store > laboratory dust, however, the difference was not statistically significant. Interestingly, levels of parabens in Vietnamese house dust exhibited an increasing trend over time, for example, mean/median concentrations of parabens in house dust samples collected in 2014, 2017, and 2019 were 245/205, 310/264, and 505/379 ng/g, respectively. Methylparaben was found at the highest frequency and concentrations in both PCPs and indoor dust samples. Mean exposure doses of total parabens through dust ingestion were estimated to be 2.02, 1.61, 0.968, 0.504, and 0.192 ng/kg-bw/d for infants, toddlers, children, teenagers, and adults, respectively. Further studies on the distribution, emission behavior, potential sources, and negative impacts of parabens in different environmental media in Vietnam are needed.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33184790

RESUMO

Concentrations and congener profiles of seven di- to hexachlorinated benzenes (CBzs) were characterized in bottom ash and fly ash samples collected simultaneously from one medical waste incinerator (MEWI) and one municipal waste incinerator (MUWI) in northern Vietnam. Total concentrations of seven CBzs in the fly ash samples ranged from 6.98 to 34.4 (median 19.1) ng g-1 in the MEWI, and ranged from 59.1 to 391 (median 197) ng g-1 in the MUWI. Concentrations of CBzs in the bottom ash samples of the MEWI (median 1.95; range 1.53-5.98 ng g-1) were also lower than those measured in the MUWI samples (median 17.4; range 14.5-42.6 ng g-1). Levels of CBzs in the fly ash samples were significantly higher than concentrations measured in the bottom ash samples, partially indicating the low-temperature catalytic formation of these pollutants in post-combustion zone. In general, higher chlorinated congeners (e.g., hexachlorobenzene, pentachlorobenzene, and 1,2,4,5-tetrachlorobenzene) were more abundant than lower chlorinated compounds. However, compositional profiles of CBzs were different between the ash types and incinerators and even between the same sample types of different sampling days, suggesting that the formation of CBzs in these incinerators is complicated and influenced by many factors. Emission factors and annual emission amounts of CBzs were estimated for the two incinerators by using actually measured data of CBz concentrations in the ash. Daily intake doses and cancer risks of ash-bound CBzs estimated for workers in the two incinerators were generally lower than critical values, but cancer risks caused by other relevant pollutants (e.g., polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and dioxin-related compounds) were not considered.

19.
Environ Pollut ; : 116012, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33187845

RESUMO

Contamination status, potential emission sources, environmental fate, and human exposure risk of polybrominated diphenyl ethers (PBDEs) are reviewed for indoor and outdoor dust from Southeast Asian countries, under an international comparison point of view. PBDEs have been widely detected in house, workplace, car, and road dust samples collected from Indonesia, Philippines, Singapore, Thailand, and Vietnam. The highest PBDE levels up to hundreds of µg/g were found in settled dust from some e-waste processing areas in Thailand and Vietnam. Concentrations of PBDEs in house, car, and road dust from this region were generally lower than those reported in China and Western developed countries. BDE-209 was the most predominant congener in almost all analyzed samples, reflecting the widespread application of materials and products treated with commercial deca-BDE mixtures in this region. The market demand and application rate of commercial PBDE mixtures in Southeast Asia were lower than those documented for other regions in the world. As a result, PBDE contamination levels in the environments (e.g., indoor and outdoor dust) and associated risks in these countries were not significantly high. However, more attention should be paid to informal processing activities and management strategies for modern wastes such as e-waste, plastics, and end-of-life vehicles. There exist several knowledge gaps about spatiotemporal trends, potential sources, risk assessment, inventory, management, and legislation regarding PBDEs in dust from this region, which should be filled by additional comprehensive, detailed studies with relevant inter-country/regional monitoring schemes.

20.
J Hazard Mater ; : 124369, 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33160782

RESUMO

This study was set up to model and optimize the performance and emission characteristics of a diesel engine fueled with carbon nanoparticle-dosed water/ diesel emulsion fuel using a combination of soft computing techniques. Adaptive neuro-fuzzy inference system tuned by particle swarm algorithm was used for modeling the performance and emission parameters of the engine, while optimization of the engine operating parameters and the fuel composition was conducted via multiple-objective particle swarm algorithm. The model input variables were: injection timing (35-41° CA BTDC), engine load (0-100%), nanoparticle dosage (0-150 µM), and water content (0-3 wt%). The model output variables included: brake specific fuel consumption, brake thermal efficiency, as well as carbon monoxide, carbon dioxide, nitrogen oxides, and unburned hydrocarbons emission concentrations. The training and testing of the modeling system were performed on the basis of 60 data patterns obtained from the experimental trials. The effects of input variables on the performance and emission characteristics of the engine were thoroughly analyzed and comprehensively discussed as well. According to the experimental results, injection timing and engine load could significantly affect all the investigated performance and emission parameters. Water and nanoparticle addition to diesel could markedly affect some performance and emission parameters. The modeling system could predict the output parameters with an R2 > 0.93, MSE < 5.70 × 10-3, RMSE < 7.55 × 10-2, and MAPE < 3.86 × 10-2. The optimum conditions were: injection timing of 39° CA BTDC, engine load of 74%, nanoparticle dosage of 112 µM, and water content of 2.49 wt%. The carbon dioxide, carbon monoxide, nitrogen oxides, and unburned hydrocarbon emission concentrations were found to be 7.26 vol% , 0.46 vol% , 95.7  ppm, and 36.2 ppm, respectively, under the selected optimal operating conditions while the quantity of brake thermal efficiency was found at an acceptable level ( 34.0 %). In general, the applied soft computing combination appears to be a promising approach to model and optimize operating parameters and fuel composition of diesel engines.

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