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Fulltext Differential-Evolution Control Parameter Optimization for Unmanned Aerial Vehicle Path Planning

Kok KY, Rajendran P

PLoS One, 2016;11(3):e0150558.
PMID: 26943630 DOI: 10.1371/journal.pone.0150558

The differential evolution algorithm has been widely applied on unmanned aerial vehicle (UAV) path planning. At present, four random tuning parameters exist for differential evolution algorithm, namely, population size, differential weight, crossover, and generation number. These tuning parameters are required, together with user setting on path and computational cost weightage. However, the optimum settings of these tuning parameters vary according to application. Instead of trial and error, this paper presents an optimization method of differential evolution algorithm for tuning the parameters of UAV path planning. The parameters that this research focuses on are population size, differential weight, crossover, and generation number. The developed algorithm enables the user to simply define the weightage desired between the path and computational cost to converge with the minimum generation required based on user requirement. In conclusion, the proposed optimization of tuning parameters in differential evolution algorithm for UAV path planning expedites and improves the final output path and computational cost.
Fulltext Hydrogen sensing enhancement of zinc oxide nanorods via voltage biasing

Choo TF, Saidin NU, Kok KY

R Soc Open Sci, 2018 May;5(5):172372.
PMID: 29892421 DOI: 10.1098/rsos.172372

The capability of zinc oxide (ZnO) as a hydrogen sensing element has been pushed to its limits. Different methods have been explored to extend its sensing capability. In this paper, we report a novel approach which significantly improves the hydrogen sensing capability of zinc oxide by applying a bias voltage to ZnO nanorods as the sensing elements. Zinc oxide in the form of aligned nanorods was first synthesized on an Au-coated Si(111) substrate using a facile method via the galvanic-assisted chemical process. The sensing performance of the zinc oxide nanorods was investigated in response to the applied biasing voltage. It was found that the sensitivity, response time and detection limit of the ZnO sensing elements were dramatically improved with increasing bias voltage. A 100% increment in sensing response was achieved for the detection of 2000 ppm hydrogen gas when the bias voltage was increased from -2 to -6 V with 70% reduction in response and recovery times. This remarkable sensing performance is attributed to the reaction of hydrogen with chemisorbed oxygen ions on the surface of the ZnO nanorods that served as the electron donors to increase the sensor conductance. Higher reverse bias voltages sweep the electrons faster across the electrodes. This shortened the response time and, at the same time, depleted the electrons in the sensor elements and weakens oxygen adsorption. The oxygen ions could then be readily removed by hydrogen, leading to a higher sensitivity of the sensors. This, therefore, envisages a way for high-speed hydrogen gas sensing with high detection sensitivities.
Fulltext A Study on the Utilization of Coal Fly Ash Derived Grog in Clay Ceramics

Choo TF, Mohd Salleh MA, Kok KY, Matori KA, Abdul Rashid S

Materials (Basel), 2020 Nov 18;13(22).
PMID: 33218206 DOI: 10.3390/ma13225218

Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics.
Erratum: Burden of disease attributable to high body mass index: an analysis of data from the Global Burden of Disease Study 2021

Zhou XD, Chen QF, Yang W, Zuluaga M, Targher G, Byrne CD, et al.

EClinicalMedicine, 2024 Dec;78:102958.
PMID: 39640937 DOI: 10.1016/j.eclinm.2024.102958

[This corrects the article DOI: 10.1016/j.eclinm.2024.102848.].
Fulltext Burden of disease attributable to high body mass index: an analysis of data from the Global Burden of Disease Study 2021

Zhou XD, Chen QF, Yang W, Zuluaga M, Targher G, Byrne CD, et al.

EClinicalMedicine, 2024 Oct;76:102848.
PMID: 39386160 DOI: 10.1016/j.eclinm.2024.102848

BACKGROUND: Obesity represents a major global health challenge with important clinical implications. Despite its recognized importance, the global disease burden attributable to high body mass index (BMI) remains less well understood.
METHODS: We systematically analyzed global deaths and disability-adjusted life years (DALYs) attributable to high BMI using the methodology and analytical approaches of the Global Burden of Disease Study (GBD) 2021. High BMI was defined as a BMI over 25 kg/m2 for individuals aged ≥20 years. The Socio-Demographic Index (SDI) was used as a composite measure to assess the level of socio-economic development across different regions. Subgroup analyses considered age, sex, year, geographical location, and SDI.
FINDINGS: From 1990 to 2021, the global deaths and DALYs attributable to high BMI increased more than 2.5-fold for females and males. However, the age-standardized death rates remained stable for females and increased by 15.0% for males. Similarly, the age-standardized DALY rates increased by 21.7% for females and 31.2% for males. In 2021, the six leading causes of high BMI-attributable DALYs were diabetes mellitus, ischemic heart disease, hypertensive heart disease, chronic kidney disease, low back pain and stroke. From 1990 to 2021, low-middle SDI countries exhibited the highest annual percentage changes in age-standardized DALY rates, whereas high SDI countries showed the lowest.
INTERPRETATION: The worldwide health burden attributable to high BMI has grown significantly between 1990 and 2021. The increasing global rates of high BMI and the associated disease burden highlight the urgent need for regular surveillance and monitoring of BMI.
FUNDING: National Natural Science Foundation of China and National Key R&D Program of China.
Global burden of disease attributable to metabolic risk factors in adolescents and young adults aged 15-39, 1990-2021

Zhou XD, Chen QF, Targher G, Byrne CD, Mantzoros CS, Zhang H, et al.

Clin Nutr, 2024 Nov 14;43(12):391-404.
PMID: 39579593 DOI: 10.1016/j.clnu.2024.11.016

BACKGROUND: Metabolic risk factors are a significant cause of global burden among adolescents and young adults, but there is a lack of attention to the burden attributable to these metabolic risk factors globally.
AIMS: This study aims to provide comprehensive estimates of five important metabolic risk factors and the attributable disease burden in people aged 15-39 years from 1990 to 2021, based on the Global Burden of Disease Study (GBD) database.
METHODS: Global total deaths and disability-adjusted life years (DALYs) were used to describe the burden attributable to five common metabolic risk factors, including high fasting plasma glucose (FPG), high low-density lipoprotein cholesterol (LDL-C), high systolic blood pressure (SBP), high body mass index (BMI), and kidney dysfunction, in adolescents and young adults. The estimated annual percentage changes (EAPC) of DALYs were utilized to depict the trends from 1990 to 2021.
RESULTS: From 1990 to 2021, the DALY rates attributable to all metabolic risk factors showed a globally significant upward trend, with EAPC reaching 33.0 % (27.4-38.7). Compared to females, males had a heavier burden and a more significant increase in deaths and DALYs attributable to metabolic risk factors. High BMI and high FPG have become the top two metabolic risk factors in 2021, with summary exposure variables (SEV) rising by 84.2 % and 53.6 %, respectively. Low-middle socio-demographic index (SDI), middle SDI, and high SDI regions experienced upward regional trends in DALY rates, while low SDI regions remained stable. Among 204 countries and territories, 101 (49.5 %) showed a significant increase in DALY rates, as indicated by the EAPC.
CONCLUSIONS: There is a substantial global burden attributable to metabolic risk factors in adolescents and young adults in 2021, especially high BMI and high FPG. This calls for further investigation and intervention to address this emerging trend.
Fulltext Erratum to: Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

Sartelli M, Weber DG, Ruppé E, Bassetti M, Wright BJ, Ansaloni L, et al.

World J Emerg Surg, 2017;12:35.
PMID: 28785301 DOI: 10.1186/s13017-017-0147-0

[This corrects the article DOI: 10.1186/s13017-016-0089-y.].
Fulltext Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

Sartelli M, Weber DG, Ruppé E, Bassetti M, Wright BJ, Ansaloni L, et al.

World J Emerg Surg, 2016;11:33.
PMID: 27429642 DOI: 10.1186/s13017-016-0089-y

Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients. The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance. The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria. An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs.