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This study attempts to compare the difference in negative pressure values using a commercially available phlegm suction device. The device was modified to enhance its suction capability of performing up to 8 cups simultaneously. First, negative pressure was measured using an analogue gauge and the DP-100 vacuum sensor to detect any negative pressure loss. Next, the cupping therapy pressure was measured on a tile floor and on various spots on the body using 8 cups. The results show that there is an insignificant difference in negative pressure readings recorded in the analogue gauge and the DP-100 vacuum sensor, indicating no major loss in vacuum pressure. Using up to 8 cups, the maximum value of the pressure on the floor was measured to be up to -36 kPa, while the maximum pressure on the forearm, calf, and the back of the body measured was up to -48 kPa, -48 kPa, and -50 kPa, respectively. In addition, all data measured on various spots on the body up to 8 cups show that the values meet the minimum negative pressure of -40 kPa required to perform wet cupping. In summary, the fabricated device can therefore be utilized to perform cupping therapy with up to 8 cups simultaneously. [ABSTRACT FROM AUTHOR]

The railway is an essential mode of transportation. Despite advances in railway safety over the past few decades, train accidents and incidents continue to be prevalent. From statistical data around 80% of railroad accidents are caused by human error. Consequently, a detailed reliability assessment for every system connected to railways must include a study of human reliability. The needs of human reliability analysis considered as an important criterion for the smooth and zero injuries operation in the complex Railway systems. The European standard EN 50126 emphasizes that human reliability is a necessary element for railway engineering. In this study of human reliability and analysis specifically a study on driver profile of an electric train. Within a complete driving operation, railway drivers are presented with a variety of error-producing conditions. These circumstances, when paired with essential human characteristics, lead to a variety of errors. Many accidents and mishaps in complex systems, including the railway system, are caused by human error. The purpose of this paper is to determine human factors influence the degree of occupational injuries by accidents. Besides that, some motivating aspects of human factor in a way that enables the concept of zero injuries in Railway Transportation Industry are introduced. [ABSTRACT FROM AUTHOR]

Cancer cells have the ability to infect nearby tissue and spread to other parts of the body. This process is known as metastasis, and it is widely recognised as the primary source of cancer cell invasion and the leading cause of death in cancer patients. We discovered specialised cellular membrane structures in invasive cancer cells that carry out a crucial phase in cancer invasion known as invadopodia. Actin rearrangement, extracellular matrix degradation, signalling transduction via membrane receptors such as the epidermal growth factor receptor and matrix metalloproteinase combination, and distribution to the invading front are all required for the creation of invadopodia. In this study, a mathematical model of invadopodia formation associated with binding of ligand and epidermal growth factor receptor (EGFR) that stimulates signal transduction is investigated. The ligand and signal equations are considered as heat equations with initial and free boundary conditions. The concentrations of signal and ligand are assumed to be equivalent to the concentration of EGFR on the plasma membrane (interface). Furthermore, the EGFR equation is derived from material derivatives of the reaction between ligand and EGFR that occurs at the interface. The EGFR velocity is equivalent to the ligand gradient. To detect the movement of the moving interface, the level set method is highlighted by designating the interface as the zero-level set function. In addition, the regular and nearby points are solved using the second-order centred difference and the ghost fluid with linear extrapolation methods, respectively. The velocity is calculated using the gradient difference between the intracellular signal and the extracellular ligand, which moves the interface. The results demonstrated that protrusions or invadopodia are produced on the plasma membrane using Matlab software. [ABSTRACT FROM AUTHOR]

Pharmaceuticals are emerging contaminants that potentially harm the environment as well as human health. Paracetamol is a common analgesic drug often detected in wastewater and surface water. The efficacy of wild algal biomass as an adsorbent to remove paracetamol from aqueous solutions was examined in this paper. Adsorption of paracetamol was carried out using three different algal biomass modification methods namely non-modified algal biomass, alkaline modified algal biomass, and acidic modified algal biomass. The paracetamol biosorption was studied through batch experiments at 30 °C, agitation speed of 150 rpm at pH of 6.8 during 120 min reaction time. The highest removal up to 63.56% and adsorption capacity of 32.56 mg/g was obtained using non-modified biomass. Overall, the results obtained suggest that wild algae biomass is a promising biosorbent for the removal of pharmaceuticals from water. [ABSTRACT FROM AUTHOR]

Rolling element bearings are widely used in machinery and heavy industries. Friction between rolling elements may cause surface damage and subsequently cause component and machine failure. Lubricant is used in the rolling contact to reduce friction and wear between the components by the formation of a lubricant film between the components. However, the use of mineral grease can be detrimental to the environment. In this work, palm grease is developed and used as a rolling contact lubricant. The experiment was carried out using a roller test rig to represent the contact in a roller bearing. The surface degradation of the roller bearing lubricated with palm oil grease with and without additives are investigated. Surface roughness measurement is performed using an Infinite Focus Microscope to characterize the surface degradation and wear. Surface roughness parameters include surface roughness (Ra), surface skewness (Rsk) and surface kurtosis (Rku) of the roller are investigated. The findings show that the roller surface lubricated with palm grease containing nanoparticles has less surface damage compared to pure palm grease. [ABSTRACT FROM AUTHOR]

Carbon Nanotube (CNT) is a material known to have a high thermal conductivity. Therefore, CNT is widely used for heat transfer applications. One of the CNT applications in heat transfer is to make nanofluids. CNT is a cylindrical molecule consisting layers of single layer carbon atom sheets (graphene). CNTs can be single walled (SWCNT) or multi-walled (MWCNT). In this study, MWCNT was used and characterized by using Scanning Electron Microscope (SEM). CNT-based nanofluids were synthesized by adding 0.01%, 0.03%, and 0.05% of CNT particles as well as 10%, 20%, and 30% Polyethylene Glycol (PEG) surfactants into distilled water. The objective of surfactants addition was to maintain the stability of nanofluids. The addition of PEG surfactant concentrations by 20% and 30% decreases the thermal conductivity of nanofluids. On the other hand, the stability of CNT-based nanofluids increases after the addition of PEG surfactants. [ABSTRACT FROM AUTHOR]

On 17th July 2016, multiple solar flares occurred on the Sun's disk as recorded by the GOES satellite. The most attractive flare is C1.4, as this solar flare holds the longest flare duration. This 5 hours and 50 minutes flare is the longest flare recorded during the day. Therefore, its related active region (AR12565) that produces this flare was observed in the multi-wavelength region to see how this kind of flare is produced. All needed data for this analysis were collected from online sites from reliable sources such as NOAA, SDO (AIA/HMI), GOES, and LASCO. In conclusion, the magnetic reconnection process produced by AR 12565 influenced the flare development and solar radio burst type III. However, this flare had low-speed coronal mass ejection and did not give any harmful effect that could threaten space or the Earth. [ABSTRACT FROM AUTHOR]

The solar activity starts decreasing as it reaches the solar minimum starting 2017. The sunspot number is decreasing, and the sun seems less active to produce solar flares and Coronal Mass Ejections (CMEs). However, there are some cases where the Sun tends to release solar radio bursts, especially Type II burst, and Type III burst as the greater the strength of the magnetic field of the plasma on the photosphere. It might be due to unbalanced magnetic free energy that triggers the process of magnetic reconnection and releases huge amounts of high energetic particles and transmits to the Earth by solar wind in the interplanetary space. The data were collected from the Space Weather website for space weather conditions, Space Weather Live websites provide an X-ray class of flares data and an e-CALLISTO network to determine types of solar radio burst. As the data collected, illustrates on 29th May 2020, two events that produce M1.1 class of flares (07:24 UT) and C9.3 class of flares (10:45 UT) at Denmark station and Greenland station. It has a high possibility to cause breakdown to radio telecommunication and causing minor radiation storms. Predictions are important for the preparation system to shut down and prevent instruments, especially satellites, from breaking down. [ABSTRACT FROM AUTHOR]

Radio Frequency Interference (RFI) is an electrical signal which has high tendency to interfere with the proper operation of electrical or electronic devices. The signal noise has the ability to affect the performance of Log Periodic Dipole Antenna (LPDA) to detect solar radio bursts and influence the quality of the solar radio burst results. In order to obtain good results of radio bursts from e-CALLISTO, identifying the highest radio frequency signal and determining the sources of interference are needed. The range of frequency to set up the Log Periodic Dipole Antenna (LPDA) is 45MHz until 870MHz. However, on 26th April 2021, we extended the frequency from 1MHz until 2000MHz to locate and identify the wide band of radio interference. This analysis was done on the rooftop of Block D in the Faculty of Applied Sciences, UiTM Shah Alam, Malaysia. The results show that the RFI level is inversely proportional to the frequency of the signal. It revealed that the highest RFI source is 51 MHz (-85.64 dBm), followed by 419.38 MHz (-89.23 dBm) and 1216.88 MHz (-97.30 dBm). The sources of signal noise indicate amateur, fixed, mobile (except aeronautical mobile) and noise from earth exploration satellite, radio location and radio navigation. Furthermore, the findings display that the RFI or signal noise has the frequency range of 300 MHz to 400 MHz which slightly disturbs solar radio burst observations, especially fast drift burst. Nevertheless, this is the best site to monitor solar radio bursts compared to other sites as it has less human activity and communication disruption. In conclusion, our aim which was to find a location that has low RFI level and radio disturbances to set up LPDA to get the best performance was completely successful. [ABSTRACT FROM AUTHOR]

This study aims to determine the effectiveness of modern optical learning devices during the covid-19 pandemic to improve the creativity and science generic skills (GSS) of students. The learning device was developed with a 4D model which includes the stages of defining, designing, developing, and disseminating. The sample used in this study was a group of master's students of science education who took modern optics courses with a total of five people. Analysis of increasing creativity and GSS using the n-gain (g) test. The results of the g analysis for all aspects indicate that creativity and GSS of students have increased with high (g > 0.7) and medium (0.3 < g < 0.7) categories. These results show that the use of modern optical learning devices is effective for increasing the creativity and GSS of students during the COVID-19 pandemic. The implication of this research is that the development of modern optical learning devices is needed to improve the creativity and generic science skills of students, especially during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

The feedstock and processing technology determined the quality of activated carbon. The ulin wood (Eusideroxylon zwageri) waste was used as activated carbon feedstock. The aim of this study was to analyze the physicochemical properties of activated carbon produced by water soaking activation at low thermal cracking temperature. At first, ulin wood was characterized by Thermal Gravimetric/Differential Scanning Calorimetry (TGA/DSC). Ulin wood waste was pyrolyzed for two hours in the absence of oxygen at 350 °C, 450 °C, and 550 °C of thermal cracking temperature. The hot char produced was then water soaked for thirty minutes to activate the char. The characteristics of activated carbon were performed by ultimate-proximate analyses, Scanning Electron Microscopy (SEM), Fourier-Transform Infra-Red spectroscopy (FT-IR), Brunauer, Emmett, and Teller (BET), and XRD (X-Ray Diffraction) analyses. To compare the activated carbon properties, it was also analyzed the conventional carbon produced without water soaking. Based on TGA/DSC, the components of lignocellulose in wood powders have decomposed at all pyrolysis temperature. The result showed that in the 550 °C thermal cracking temperature, the fixed carbon, total carbon, ash content, and pH were increased, but volatile matter, yield, oxygen, and hydrogen were decreased. Carbon activation by water soaking could clean the char from the surface dust. Based on SEM analysis, the higher the thermal cracking temperature, the more ordered macroporous char. There was a functional group similarity between activated and conventional char. As increasing thermal cracking temperature, the organic functional groups had a high aromatic of C-H, C=C, C=O groups. BET surface areas of activated carbon of ulin wood were ranged between 175.97 m2/g – 218.88 m2/g. The calorific value was increased from 6,728.67 cal/g to 7,128.14 cal/g as increased pyrolysis temperature. The sharp diffraction peaks based on XRD analysis indicated that there was the structure of the graphite crystalline in activated carbon. [ABSTRACT FROM AUTHOR]

Noble metals (Au and Ag) are the primary raw materials which have vast potential application ranging from across biosensor, biomedicine, science, and engineering fundamental. However, alloying them will enhance the efficiency and applicability of noble metals. Employing the linear-weight (LW) technique to construct a dielectric function of a binary solution is still disputed. However, this method is still widely used to examine Localized Surface Plasmon Resonance (LSPR) of Au-Ag binary solution. In this work, the calculation of electromagnetic response such as Localized Surface Plasmon Resonance (LSPR) of bimetallic Au-Ag nanorod was performed by means of MNPBEM package. We utilized nanorod-shaped with two different excitation modes, namely, Transverse Mode (TM) and Longitudinal Mode (LM), and various compositions to investigate their LSPR shifting anomalies. Moreover, we employed the LW technique to construct their dielectric function and analyze the LSPR anomalies. Interestingly, we found that using LW approximation, the resonance peak of TM is separate into two peaks. These peaks originated from the free electron of Au and Ag respectively, however, some of LSPRs peak did not occur amongst peak of pure Au and Ag. Practically, using LW method the resonance peak should be located amongst their individual elements. This work has provided the limitation of using silver fraction and the related aspect ratios to predict the LSPR spectra of Au and Ag on nanorod-shaped. [ABSTRACT FROM AUTHOR]

The primary interest in numerous research problems in both polymer composites and Machine Learning (ML) is to develop predictive models for one or more variables of interest using relevant independent variables, or inputs. However, these two fields have often adopted different approaches, where modeling of composite behavior is often based on physics-based models and phenomenological theories. These physical models are more precise and robust, but often suffer from restricted predictive capability since they are confined to a specific set of conditions. ML models, on the other hand, can be more efficient during the design phase as they allow managing massive and high dimensional data sets to extract the best fit or a predictive behavior for the application at hand. In this context, material scientists would benefit from understanding and implementing some of the powerful ML methods, in order to predict or characterize a behavior of interest of a polymer composite. In this paper, we present a general methodology aimed at employing supervised machine learning models for predicting the properties of polymer composites, including thermo-mechanical properties, environmental effects such as moisture saturation level, durability, or other important behavior, based on the composite constituents, manufacturing processes, relevant process parameters, and expected life-span of the composite product. [ABSTRACT FROM AUTHOR]

This paper proposes a simple and accurate technique to quantify both fiber and void volume fractions of natural fiber composites. This technique involves the separate pyrolysis of natural fibers, polymer resin, and natural fiber/polymer composite in a pure nitrogen atmosphere. The remained fractional residuals of these materials are used for the determination of fiber and matrix weight fractions. Consequently, the void and fiber volume fractions of the natural fiber composite are calculated by having weight fractions, as well as the density of natural fiber, epoxy resin, and composite sample. To validate this new method, a number of silk/epoxy composites at various levels of void content were manufactured. Specific results are given for the random mat silk/epoxy laminates made by wet lay-up vacuum bagging (WLVB) process, as well as plain weave silk/epoxy laminates fabricated by the vacuum assisted resin transfer molding (VARTM) process. Using the proposed method, the void volume fractions of the random mat and plain weave silk composites are calculated to be 9.5% and 1.7%, respectively. The fiber volume fraction of random mat and plain weave laminates are also determined to be 18.7% and 46.3%, respectively. The representative scanning electron microscopy (SEM) images of those laminates are also presented to visually compare the void and fiber contents of the parts. The results demonstrate that the proposed method enables an accurate determination of the fiber and void contents in silk/epoxy laminates and can be extended to composites containing other types of natural fibers. [ABSTRACT FROM AUTHOR]

In this communication, the state space method is used to analyze the dynamic behavior in Laplace domain of laminated magneto-electro-elastic rectangular plates with viscoelastic interfaces and simply supported boundary conditions based on a Winkler-Pasternak elastic Foundation, and then it is transferred to the time domain by the Fourier inversion method. The Kelvin-Voigt model is used to take into accounted the viscoelastic interface effects. The mathematical formulation is elaborated in a general form and an arbitrary number of layers as well as the orthotropic behavior can be considered. The methodology is based on the mixed formulation, in which basic unknowns are formed by collecting displacements, stresses, electrical displacements, electrical potential, magnetic induction and magnetic potential. As special case, multilayered rectangular plate is analyzed under the surface loading with simply supported boundary conditions based on an elastic foundation. A variant numerical tests shown the effect of the Winkler-Pasternak Foundation on a magneto-electro-elastic rectangular plates dynamic behavior and may contribute to optimize the design and the manufacturing of these materials. [ABSTRACT FROM AUTHOR]

In this communication, a methodological approach based on the combination of the state space method and the differential quadrature method (SS-DQM) is used to analyze the static and dynamic behavior of magneto-electro-elastic rectangular plates with viscoelastic interfaces based on a Winkler-Pasternak elastic support and with different boundary conditions. The state space method is used to estimate the solution in the thickness direction with an arbitrary number and different types of layers, whereas the DQM method is used to take into account all the boundary conditions. Afterward, to convert the obtain solutions from Laplace domain to temporary one we use the inverse Laplace transform. [ABSTRACT FROM AUTHOR]

The needs to treat wastewater from plants and factories before releasing it to the environment is crucial to remove unwanted pollutants such as high concentration of heavy metals which may affect the environment. Adsorption via activated carbon (AC) has shown good traits in removing heavy metals in aqueous solution. In this research, rubber-seed shell (RSS), which is low cost and available abundantly, was tested as a precursor to produce porous carbons in a chemical scheme using chitosan. From synthesis parameters studied, AC with the largest surface area (530.73 m²/g), pore volume (0.2977 cm²/g) and pore diameter (2.243 nm), which majority consist of mesopores was obtained when RSS is impregnated with ratio of 1:2 and treated with activation temperature of 700°C for a period of 120 minutes. The results from adsorption test showed that under the effect of low concentration of 100ppm, sample C3 can remove 74.16% of Cu2+ and 76.15% of Pb2+. Under the influence of temperature of 25°C, highest 71.4% of Cu2+ and 72.93% of Pb2+ removal was observed while time taken to achieve equilibrium are 105 and 75 minutes, respectively. Based on the analysis, it inferred that the adsorption of Pb2+ fits the pseudo-first order (R = 0.9751) with root mean error of 1.006% while adsorption of Cu2+ fits the pseudo-second order (R = 0.9776) with root mean of 1.178%. The obtained results show that agriculture waste product from RSS can be effectively used as an adsorption material. [ABSTRACT FROM AUTHOR]