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Fulltext Author Correction: Enhancement in heat transfer due to hybrid nanoparticles in MHD flow of Brinkman-type fluids using Caputo fractional derivatives

Sheikh NA, Ching DLC, Khan I, Sakidin HB

Sci Rep, 2022 Dec 16;12(1):21772.
PMID: 36526701 DOI: 10.1038/s41598-022-26239-2
Fulltext Enhancement in heat transfer due to hybrid nanoparticles in MHD flow of Brinkman-type fluids using Caputo fractional derivatives

Sheikh NA, Ching DLC, Khan I, Sakidin HB

Sci Rep, 2022 Aug 18;12(1):14117.
PMID: 35982149 DOI: 10.1038/s41598-022-18110-1

The flow of fluid through porous media is of great importance in industry and other physical situations, Darcy's law is one of the most useful laws to describe such situation, however, the flows through a dense swarm of particles or through a very high porous media cannot be elaborated by this law. To overcome this difficulty, Brinkman proposed a new idea of Brinkman-type fluid in highly porous media. In this study, the Brinkman-type fluid flow is analyzed with hybrid nanoparticles (a hybridized mixture of clay and alumina), suspended in water taken as a base fluid under the effect of an applied magnetic field. The fluid motion is taken inside a vertical channel with heated walls. Free convection is induced due to buoyancy. The momentum and energy equations are written in dimensionless form using the non-dimensional variables. The energy equation is modified to fractional differential equations using the generalized Fourier's law and the Caputo fractional derivatives. The fractional model is solved using the Laplace and Fourier transformation. Variations in velocity and temperature are shown for various fractional parameter values, as well as charts for the classical model. For the volume fractions of nanoparticles, the temperature distribution increases, with maximum values of hybrid nanoparticles with the highest specified volume fractions. Moreover, due to hybrid nanoparticles, the rate of heat transfer is intensified.
Fulltext Fractional model for MHD flow of Casson fluid with cadmium telluride nanoparticles using the generalized Fourier's law

Sheikh NA, Ching DLC, Khan I, Sakidin HB, Jamil M, Khalid HU, et al.

Sci Rep, 2021 Aug 09;11(1):16117.
PMID: 34373521 DOI: 10.1038/s41598-021-95528-z

The present work used fractional model of Casson fluid by utilizing a generalized Fourier's Law to construct Caputo Fractional model. A porous medium containing nanofluid flowing in a channel is considered with free convection and electrical conduction. A novel transformation is applied for energy equation and then solved by using integral transforms, combinedly, the Fourier and Laplace transformations. The results are shown in form of Mittag-Leffler function. The influence of physical parameters have been presented in graphs and values in tables are discussed in this work. The results reveal that heat transfer increases with increasing values of the volume fraction of nanoparticles, while the velocity of the nanofluid decreases with the increasing values of volume fraction of these particles.
Fulltext Laser-Assisted High Speed Machining of 316 Stainless Steel: The Effect of Water-Soluble Sago Starch Based Cutting Fluid on Surface Roughness and Tool Wear

Yasmin F, Tamrin KF, Sheikh NA, Barroy P, Yassin A, Khan AA, et al.

Materials (Basel), 2021 Mar 09;14(5).
PMID: 33803364 DOI: 10.3390/ma14051311

Laser-assisted high speed milling is a subtractive machining method that employs a laser to thermally soften a difficult-to-cut material's surface in order to enhance machinability at a high material removal rate with improved surface finish and tool life. However, this machining with high speed leads to high friction between workpiece and tool, and can result in high temperatures, impairing the surface quality. Use of conventional cutting fluid may not effectively control the heat generation. Besides, vegetable-based cutting fluids are invariably a major source of food insecurity of edible oils which is traditionally used as a staple food in many countries. Thus, the primary objective of this study is to experimentally investigate the effects of water-soluble sago starch-based cutting fluid on surface roughness and tool's flank wear using response surface methodology (RSM) while machining of 316 stainless steel. In order to observe the comparison, the experiments with same machining parameters are conducted with conventional cutting fluid. The prepared water-soluble sago starch based cutting fluid showed excellent cooling and lubricating performance. Therefore, in comparison to the machining using conventional cutting fluid, a decrease of 48.23% in surface roughness and 38.41% in flank wear were noted using presented approach. Furthermore, using the extreme learning machine (ELM), the obtained data is modeled to predict surface roughness and flank wear and showed good agreement between observations and predictions.
Fulltext Laser Discoloration in Acrylic Painting of Visual Art: Experiment and Modeling

Tamrin KF, Moghadasi K, Jalil MH, Sheikh NA, Mohamaddan S

Materials (Basel), 2021 Apr 16;14(8).
PMID: 33923675 DOI: 10.3390/ma14082009

This study discloses a method for painting artwork using a CO2 laser. The continuous-wave laser beam, at a predetermined heat flux and a predetermined number of laser beam passes, mixes and displaces the plurality of colored polymer-based compositions, respectively, by way of melting and vaporizing them. Experiments showed a great accuracy of colors and designed patterns between the computer aided design (CAD) drawing and what was achieved after laser discoloration. It was found that lower values of power and speed provide sufficient energy and time to make a melt pool of colors and cause their vaporization from the surface. A detailed numerical simulation was performed to obtain a detailed understanding of the physics of laser interaction with paint using ABAQUS software. The comparative analysis indicated that the top layer of paint (including yellow and green colors) melted upon increasing cutting speed and employing one laser pass. For blue and red paints, two passes of lasers are required; in the case of red color, lower laser speed is also necessary to intensify the heat. This method can be applied for making art designs on each surface color because it is based on melting and vaporization using a laser.
Fulltext Global Burden of Anorexia Nervosa and Bulimia Nervosa, 1990 to 2023, With Forecasts to 2050: A Global Burden of Disease Study 2023 Analysis

Bai R, Dong W, Wang X, Zhang A, Santomauro DF, GBD Eating Disorders Collaborators, et al.

JAMA Psychiatry, 2026 Oct 28.
PMID: 42949727 DOI: 10.1001/jamapsychiatry.2026.3457

IMPORTANCE: Eating disorders are a major cause of nonfatal mental health burden, yet global evidence on their long-term trends, geographic distribution, and future trajectories remains limited.
OBJECTIVE: To estimate the global, regional, and national prevalence and disability burden of anorexia nervosa and bulimia nervosa-and mortality attributable to anorexia nervosa-from 1990 to 2023, and to forecast prevalence to 2050.
DESIGN, SETTING, AND PARTICIPANTS: Using Global Burden of Disease (GBD) 2023 methods, data were synthesized from systematic literature reviews, population surveys, and vital registration systems. Estimates were produced for 204 countries and territories from 1990 to 2023, with forecasts through 2050. These data were analyzed from October 2025 to August 2026.
EXPOSURE: Anorexia nervosa or bulimia nervosa diagnosis.
MAIN OUTCOMES AND MEASURES: Counts and age-standardized rates with 95% uncertainty intervals (UIs) for anorexia nervosa and bulimia nervosa prevalence, years lived with disability (YLDs), and disability-adjusted life-years (DALYs), and anorexia nervosa mortality, reported by age, sex, and location.
RESULTS: In 2023, an estimated 18.1 million people (95% UI, 13.9-24.0) globally were living with anorexia nervosa or bulimia nervosa, of whom 12.6 million (69.4%) were female, 5.5 million were male (30.6%), and 41.2% were aged 10 to 24 years. These cases accounted for 3.83 million DALYs (95% UI, 2.23-5.69). Since 1990, the global number of prevalent cases increased by 71.0%, while age-standardized prevalence and DALY rates rose by about 21%. Females experienced substantially higher prevalence and DALY rates than males. The highest age-standardized prevalence rates were observed in high-income regions, particularly Australasia and Western Europe, whereas the largest relative increases in age-standardized prevalence occurred in East Asia, South Asia, and Southeast Asia. Forecasts indicate continued increases in prevalent cases through 2050.
CONCLUSIONS AND RELEVANCE: This GBD 2023 analysis found that anorexia nervosa and bulimia nervosa contribute substantially to global nonfatal health loss. These findings support the integration of eating disorders into mental health surveillance, prevention, and service planning worldwide.