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Electric field distribution analysis generated by ECCT in a human head model with or without brain cancer using wire mesh electrode has been conductedsuccessfully. The analysis of electric field distribution was done using simulation in a human head model with ECCT Apparel Helmet system type A which is three dimensional model. The electric field distribution was measured with and without a wire mesh electrode which was either passive or active using COMSOL Multiphysics 5.2 software and was then processed using MATLAB R2010a. The aim of the research was to assess the performance of wire mesh electrode in detecting electric field distribution. ECCT which is utilized in brain cancer therapy with input 10 V is able to produce an electric field with an average of 178.8 V/m. The input voltage influences electric field distribution whereas the signal frequency does not affect the electric field distribution. Wire mesh electrode which is either active or passive can measure the electric field distribution generated by ECCT that neither the active nor the passive wire mesh electrode changed the pattern of the electric field distribution and the change in the measured electric field value is not significant. [ABSTRACT FROM AUTHOR]

Optical logic gates for OR-AND-NOT, NOR and exclusive-XNOR operations in waveguides consisting of nonlinear material are numerically investigated by means of FD-BPM (Finite Difference Beam Propagation Method). The proposed devices are designed utilizing the self-routing characteristics of nonlinear X-crossing and Ybranching structures when they are operated with one input beam or two. The numerical simulations show that the proposed structures can favorably be applied to optical data processing and computing as fundamental logic gates. [ABSTRACT FROM AUTHOR]

This study aims to develop Various Age-size Pediatric Chest Phantoms (VAPC) to evaluate low-dose protocol that approximates clinical conditions achieved by low organ-specific doses and optimal image quality among the challenges of pediatric size variations. Three original pediatric data aged 1, 4, and 7 years were used as a reference for developing VAPC phantoms. Six protocols, namely standard dose (STD) and low dose (low mA and low kV) reconstructed using Filtered Back Projection (FBP) and iterative reconstruction (IR) algorithms, were investigated. This study directly measured the lungs, heart, and spinal cord dose using LD-V1 film. Linearity, Modulation Transfer Function (MTF), Contrast to Noise Ratio (CNR), and Noise Power Spectrum (NPS) were evaluated to assess the CT image quality of the VAPC phantom. This study found that the mean organ-specific dose was higher than CTDIvol. A Comparison of mean lung doses showed VAPC phantom 1 (y.o.) received 74.8% and 137.2% more doses than 4 (y.o.) and 7 (y.o.), respectively. Low kV produces a lower organ dose than low mA. The linearity of CT numbers is not biased at low doses. Differences in age measures significantly influenced organ-specific dose, MTF, CNR, and NPS. Smaller pediatrics are still exposed to higher doses at low-dose examinations, whereas larger pediatrics have lower contrast resolution and increased image noise. CT number linearity is unbiased. The combination of low kV with FBP produces higher spatial resolution, while low mA with IR effectively reduces noise to detect low-contrast objects better. [ABSTRACT FROM AUTHOR]

The bactericidal effect of 405 nm light was investigated on taxonomically diverse bacterial pathogens from the genera Salmonella, Shigella, Escherichia, Listeria, and Mycobacterium. High-intensity 405 nm light, generated from an array of 405-nm light-emitting diodes (LEDs), was used to inactivate bacteria in liquid suspension and on exposed surfaces. L. monocytogenes was most readily inactivated in suspension, whereas S. enterica was most resistant. In surface exposure tests, L. monocytogenes was more susceptible than Gram-negative enteric bacteria to 405 nm light when exposed on an agar surface but interestingly less susceptible than S. enterica after drying onto PVC and acrylic surfaces. The study findings, that 405 nm light inactivates diverse types of bacteria in liquids and on surfaces, in addition to the safety advantages of this visible (non-UV wavelength) light, indicate the potential of this technology for a range of decontamination applications. [ABSTRACT FROM AUTHOR]

Urbanization is a contributing factor to global warming, as asphalt, concrete, and other light-absorbing materials replace vegetated areas, causing an increase in Land Surface Temperature (LST) and creating Surface Urban Heat Islands (SUHI). Although thermal satellite imagery has been a powerful tool in mapping LST and SUHI spatio-temporal changes, the number of studies in Africa, including Egypt, remains limited. Thus, in this research, an automated model was developed in ArcGIS and used to map LST and SUHI and detect Urban Hot Spots (UHS) in Alexandria city, Egypt, using Landsat 8 time series (2013 to 2021). The results revealed an increase of 41.31% in urban areas and a decrease of 49.51% in agricultural areas, a change that was demonstrated by a decline in the Normalized Difference Vegetation Index (NDVI) from 0.84 in 2013 to 0.53 in 2021. Correspondingly, LST and SUHI displayed an increasing pattern, with the highest recorded values observed in 2021. Thus, this study showed the negative impact of urbanization on Alexandria city's temperature - a city that is already facing a climate catastrophe because of the sea level rise resulting from climate change. Furthermore, the developed estimation model can be similarly useful for climate change researchers and decision makers. [ABSTRACT FROM AUTHOR]

The development of silver (Ag) thin films and the fabrication of Ag nanosquare arrays with the use of an anodic aluminum oxide (AAO) template and leaf extracts were successfully carried out using the DC sputtering and spin coating deposition methods. Ag thin films and Ag nanosquare arrays are developed to monitor cancer prognosis due to the correlation between serum albumin levels and prognostic factors, as well as the binding of serum albumin to the surface of these electrodes. Nanosquare structures were fabricated using AAO templates with varying diameters and a gap distance between adjacent unit cells of 100 nm. The nanosquare array with a diameter of 250 nm and irradiated with electromagnetic waves with a wavelength of around 800 nm possessed the greatest electric field distribution compared to the other variations of diameters and wavelengths. The results of the absorption measurement and simulation showed a greater shift in absorption peak wavelength when carried out using the Ag nanosquare array. The absorption peak wavelengths of the Ag nanosquare array in normal blood and blood with cancer lymphocytes were 700–774 nm and 800–850 nm, respectively. The electrochemical test showed that the sensitivity values of the Ag thin-film electrode deposited using DC sputtering, the Ag thin-film electrode deposited using spin coating, and the Ag nanosquare array in detecting PBS+BSA concentration in the cyclic voltammetry (CV) experiment were 1.308 µA mM−1cm−2, 0.022 µA mM−1cm−2, and 39.917 µA mM−1cm−2, respectively. Meanwhile, the sensitivity values of the Ag thin film and the Ag nanosquare array in detecting the PBS+BSA concentration in the electrochemical impedance spectroscopy (EIS) measurement were 6593.76 Ohm·cm2/mM and 69,000 Ohm·cm2/mM, respectively. Thus, our analysis of the optical and electrochemical characteristics of Ag thin films and Ag nanosquare arrays showed that both can be used as an alternative biomedical technology to monitor the prognosis of blood cancer based on the concentration of serum albumin in blood. [ABSTRACT FROM AUTHOR]

Sol-gel and coprecipitation methods successfully prepared titanium dioxide (TiO2) powders with anatase structure. The TiO2 powders are then used to fabricate pure TiO2 thin-film or mixed with SnO2 powders for the TiO2/SnO2 composite thin film. Furthermore, the structural, morphological, as well as the optical properties of films were also investigated. The results showed that the synthesized thin-film of TiO2 powders by sol-gel method obtained better crystallinity and microstructure compared to the synthesized thin film by co-precipitation method. In the DSSC system, these features are needed to increase the electron mobility that responsibility for transport and recombination of photoexcited electrons. SEM images exhibited the smooth surface and uniform in particle size obtained by the addition of SnO2 powders in composite films. The composite thin film also indicated a higher transmittance value. Keywords: sol-gel,co-precipitation,anatase, composite.

Background: Type 1 diabetes mellitus (T1DM) is the most common chronic disease in children, with several severe short and long-term complications. Glycemic control is an important aspect of diabetes management with the most influential factor being compliance with self-monitoring blood glucose (SMBG). Mostly, in Indonesia, the finger stick devices as a glucose monitoring tool were frequently used. About 20% of children follow the recommendation to measure blood glucose four to six times daily., Methods: This is a single center, cross-sectional study that was conducted between July-November 2022. The Population is children with T1DM at the Pediatric Outpatient Clinic of Dr. Soetomo Hospital, Surabaya, Indonesia. Children with T1DM aged 4-18 years were enrolled using consecutive sampling. A compliance questionnaire was used to assess SMBG. Psychosocial conditions were assessed using the Pediatric Symptom Checklist 17, and medication adherence was evaluated using the Adherence to Refills and Medications Scale for Diabetes (ARMS-D). Pearson correlation and linear regression were employed for statistical analyses using Statistical Package for Social Sciences version 21.0, with p < 0.05 indicating statistical significance., Results: A total of 36 children were included in this study. SMBG frequency over 4x per day was significantly associated with increased medication adherence as measured by the ARMS-D score (p = 0.012). Higher SMBG frequency was also correlated with decreased HbA1c (p = 0.014, r = 0.406) and nutritional status (p = 0.031, r = 0.360). Less than 50% of the patients in Indonesia adhered to the recommended guidelines for SMBG (ie, ≥4 times per day)., Conclusion: Higher SMBG frequency was correlated with better glycemic control. This finding suggests the need for further support in conducting SMBG based on the national guideline. However, due to it being conducted in a single center, we suggest increasing the sample size or conducting multi-centre collaborations in future studies., Originality/value: By specifically investigating the relationship between adherence to self-monitoring of blood glucose (SMBG) and glycemic control in children with type 1 diabetes mellitus (T1DM), our study represents a novel contribution to the field of pediatric diabetes management in Indonesia. While previous research has explored similar relationships in other populations, our study focuses exclusively on the unique context of Indonesia, where rates of adherence to SMBG in pediatric patients have not been well studied and are relatively low compared to global standards., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Rochmah et al.)

This study aimed to quantitatively assess the radiation dose using XR-QA2 and the image quality of the dual-energy subtraction mammography technique on an in-house phantom. The analysis was carried out to investigate the effect of targets/filters on dose value and image quality using an in-house phantom made of PLA + as an object representing compressed breasts. All irradiation parameters were performed in the craniocaudal position with manual mode. Mean glandular dose (MGD) was recorded, followed by the calculation of the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and modulation transfer function (MTF) for image quality assessment parameters. The results showed that the image quality was accepted at dose levels within the IAEA and BAPETEN tolerance limit for 60 mm equivalent compressed breast using dual-energy mammography. Furthermore, the target/filter (W/Rh) reduced the dose by 1.03 mGy compared to the Mo/Mo and Mo/Rh with an enhancement in image quality. This indicated that the target/filter (W/Rh) combination was optimal due to the image quality improvement obtained with lower MGD., (© 2023. Australasian College of Physical Scientists and Engineers in Medicine.)

TMP is gradually becoming a fundamental element for quality assurance and control in ionizing and non-ionizing radiation imaging modalities as well as in the development of different techniques. This study aimed to evaluate and obtain polyvinyl chloride tissue mimicking material for dual-modality breast phantoms in mammography and ultrasound. Breast tissue equivalence was evaluated based on X-ray attenuation properties, speed of sound, attenuation, and acoustic impedance. There are six samples of PVC-plasticizer material with variations of PVC concentration and additives. The evaluation of X-ray attenuation was carried out using mammography from 23 to 35 kV, while the acoustic properties were assessed with mode A ultrasound and a transducer frequency of 5 MHz. A breast phantom was created from TMP material with tissue equivalence and was then evaluated using mammography as well as ultrasound to analyze its image quality. The results showed that samples A (PVC 5%, DOP 95%), B (PVC 7%, DOP 93%), C (PVC 10%, DOP 90%), E (PVC 7%, DOP 90%, graphite 3%), and F (PVC 7%, DOP 90%, silicone oil 3%) have the closest equivalent to the ACR breast phantom material with a different range of 0.01-1.39 in the 23-35 kV range. Based on the evaluation of the acoustic properties of ultrasound, A had high similarity to fat tissue with a difference of 0.03 (dB cm - 1  MHz - 1 ) and 0.07 (10 6  kg m - 2  s - 1 ), while B was close to the glandular tissue with a difference of 9.2 m s - 1 . Multilayer breast phantom images' results showed gray levels in mammography and ultrasound modalities. Therefore, this study succeeded in establishing TMP material for mammography and ultrasound. It can also be used for simple quality assurance and control programs., (© 2023. Australasian College of Physical Scientists and Engineers in Medicine.)

Background: The patient-specific 3D printed anthropomorphic phantom is used for breast cancer after mastectomy developed by the laboratory of medical physics and biophysics, Department of Physics, Institut Teknologi Sepuluh Nopember, Indonesia. This phantom is applied to simulate and measure the radiation interactions occurring in the human body either using the treatment planning system (TPS) or direct measurement with external beam therapy (EBT) 3 film., Objective: This study aimed to provide dose measurements in the patient-specific 3D printed anthropomorphic phantom using a TPS and direct measurements using single-beam three-dimensional conformal radiation therapy (3DCRT) technique with electron energy of 6 MeV., Material and Methods: In this experimental study, the patient-specific 3D printed anthropomorphic phantom was used for post-mastectomy radiation therapy. TPS on the phantom was conducted using a 3D-CRT technique with RayPlan 9A software. The single-beam radiation was delivered to the phantom with an angle perpendicular to the breast plane at 337.3° at 6 MeV with a total prescribed dose of 5000 cGy/25 fractions with 200 cGy per fraction., Results: The doses at planning target volume (PTV) and right lung confirmed a non-significant difference both for TPS and direct measurement with P -values of 0.074 and 0.143, respectively. The dose at the spinal cord showed statistically significant differences with a P -value of 0.002. The result presented a similar skin dose value using either TPS or direct measurement., Conclusion: The patient-specific 3D printed anthropomorphic phantom for breast cancer after mastectomy on the right side has good potential as an alternative to the evaluation of dosimetry for radiation therapy., Competing Interests: None, (Copyright: © Journal of Biomedical Physics and Engineering.)

Background: Calibration of Thermo Luminescent Dosimetry (TLD) in eye lens dosimeter requires a standard phantom. The use of anthropomorphic phantoms in calibration needs evaluation., Objective: This study aimed to analyze the angular response of the TLD on the fabricated 3D anthropomorphic head phantom and Computerized Imaging Reference Systems (CIRS)- Computed Tomography (CT) dose phantom as a standard phantom irradiated with Cs-137 and to compare the absorbed dose and linear attenuation for both phantoms. H p (3) analysis, conversion coefficient (h pK (3)), and calibration factor (CF) are also investigated., Material and Methods: In this experimental study, the fabricated 3D printed anthropomorphic head phantom was analyzed using polylactic acid (PLA) with the skull and then filled with the artificial brain and cerebrospinal fluid (CSF) as a test phantom. TLD-700H and TLD Reader Harshaw 6600 plus were used to analyze the angular response of Cs-137 radiation and to determine the absorbed dose and linear attenuation coefficient of test and standard phantoms., Results: The effect of the angle of radiation source towards TLD reading at the anthropomorphic head phantom has a similar value to the standard phantom with a calibration factor ranging from 0.82 to 1. The absorbed dose measurement and the linear attenuation coefficient of the anthropomorphic head phantom with the standard phantom have different values of 2.52 and 3.78%, respectively., Conclusion: The fabricated 3D printed anthropomorphic head phantom has good potential as an alternative to standard phantoms for TLD calibration in eye lens dosimeter., Competing Interests: None, (Copyright: © Journal of Biomedical Physics and Engineering.)

Background: The use of boluses for radiation therapy is very necessary to overcome the problem of sending inhomogeneous doses in the target volume due to irregularities on the surface of the skin. The bolus materials for radiation therapy need to be evaluated., Objective: The present study aims to evaluate some handmade boluses for megavoltage electron and photon radiation therapy. Several dosimetric properties of the synthesized boluses, including relative electron density (RED), transmission factor, mass attenuation coefficient, percentage depth dose (PDD), and percentage surface dose (PSD) were investigated., Material and Methods: In this experimental study, we evaluated natural rubber, silicone rubber mixed either with aluminum or bismuth, paraffin wax, red plasticine, and play-doh as soft tissue equivalent. CT-simulator, in combination with ECLIPSE software, was used to determine bolus density. Meanwhile, Linear Accelerator (Linac) Clinac iX (Varian Medical Systems, Palo Alto), solid water phantom, and Farmer ionization chamber were used to measure and analyze of dosimetric properties., Results: The RED result analysis has proven that all synthesized boluses are equivalent to the density of soft tissue such as fat, breast, lung, and liver. The dosimetric evaluation also shows that all synthesized boluses have a density similar to the density of water and can increase the surface dose with a value ranging from 6-20% for electron energy and 30-50% for photon energy., Conclusion: In general, all synthesized boluses have an excellent opportunity to be used as an alternative tissue substitute in the surface area of the body when using megavoltage electron and photon energy., (Copyright: © Journal of Biomedical Physics and Engineering.)

The bactericidal effect of 405 nm light was investigated on taxonomically diverse bacterial pathogens from the genera Salmonella, Shigella, Escherichia, Listeria, and Mycobacterium. High-intensity 405 nm light, generated from an array of 405-nm light-emitting diodes (LEDs), was used to inactivate bacteria in liquid suspension and on exposed surfaces. L. monocytogenes was most readily inactivated in suspension, whereas S. enterica was most resistant. In surface exposure tests, L. monocytogenes was more susceptible than Gram-negative enteric bacteria to 405 nm light when exposed on an agar surface but interestingly less susceptible than S. enterica after drying onto PVC and acrylic surfaces. The study findings, that 405 nm light inactivates diverse types of bacteria in liquids and on surfaces, in addition to the safety advantages of this visible (non-UV wavelength) light, indicate the potential of this technology for a range of decontamination applications.