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Introduction: The study aimed to analyze and determine impact of the 3D-CRT fractionation on risk of secondary cancer. Material and Methods: This study used a patient-specific anthropomorphic phantom, and radiation was performed using the Three Dimensional-Conformal Radiation Therapy Field in Field (3D-CRT FinF) technique with conventional, hypofractionation, and hyperfractionation with a dose of 200 cGy, 260 cGy, and 160 cGy in 25, 16, and 30 fractions respectively. It focused on the contralateral breast, contralateral lung, and ipsilateral lung as Organs at Risk (OAR). In addition, the Dose Volume Histogram (DVH) value, normal tissue complication probability (NTCP), and risk of secondary cancer were evaluated.Results: The results showed that the average dose value (Dmean) for ipsilateral lung with hypofractionation was smaller than conventional and hyperfractionation of 1519.8, 1826.7, and 1753.6 cGy, respectively. Furthermore, hypofractionation also reduced radiobiological effects by 50% in the ipsilateral lung with an NTCP value of 0.01% compared to conventional and hyperfractionation with a value of 0.02%. Hypofractionation reduces the risk of secondary cancer in the contralateral breast, contralateral lung, and ipsilateral lung by 16.38, 17, and 22.31% compared to conventional fractionation and 12.75, 13.54, and 21.34% compared to hyperfractionation, respectively. Conclusion: The dose profiles in OAR was smaller in treatment planning with hypofractionation. EBT3 film verification results showed that the ipsilateral lung received more doses than planned, with an insignificant difference (p>0.05). In radiobiology, the ipsilateral lung has the highest probability of complications in treatment planning with conventional fractionation and hyperfractionation.

Nur Rochmah,1,2 Soetjipto Soetjipto,3 Muhammad Faizi,1,2 Yuni Hisbiyah,1,2 Rayi Kurnia Perwitasari,1,2 Katherine Fedora,1,2 Laili Nur Rosyidah,4 Endarko Endarko,5 Djoko Kuswanto,6 Eka Agustia Rini7 1Department of Child Health, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia; 2Department of Child Health, Dr. Soetomo General Teaching Hospital, Surabaya, Indonesia; 3Department of Medical Biochemistry, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia; 4Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia; 5Faculty of Science and Data Analysis, Sepuluh Nopember Institute of Technology, Surabaya, Indonesia; 6Faculty of Creative Design and Digital Business, Sepuluh Nopember Institute of Technology, Surabaya, Indonesia; 7Department of Child Health, Faculty of Medicine, Universitas Andalas, Padang, IndonesiaCorrespondence: Soetjipto Soetjipto, Department of Medical Biochemistry, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia, Tel +6281331340518, Email soetjipto1950@gmail.comBackground: 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.Keywords: Diabetes mellitus type-1, medication adherence, glycemic control, HbA1c, children, self-monitoring blood glucose

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.

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. Hp(3) analysis, conversion coefficient (hpK(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.

3D printing technology was capable of fabricating phantoms to enhance quality assurance in radiation therapy. The ideal phantom has properties equivalent to the real tissue. However, 3D Printing has the limits to mimicking the attenuation properties of various tissues because during 3D printing there can be only one type of material. The purpose of this study was to evaluate the effect of infill percentage and infill patterns of 3D printing technology to simulate various types of tissue. This study used 25 samples measuring 5 × 5 × 1 cm3 from PETG material. The 20 samples were printed using variations infill percentages from 5 - 100% and the infill pattern in lines. The five samples were then printed with the infill percentage constant at 50% and used the infill pattern triangles, grid, gyroid, octet, and concentric. We used Computed Tomography (CT) to determine the Hounsfield Unit (HU) value for each sample and evaluated the suitability of each sample for phantom applications in radiation therapy and radiology. However, none of the samples was able to simulate compact bone. As a result, we found that PETG material could simulate the properties of soft tissue, fat, lung, kidney, liver, pancreas, and spongy bone. Thus, the study had shown promising potential for the fabrication of the anthropomorphic phantom of radiation therapy.

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.

Blood cancer causes a significant increase in the concentration of Leukocytes, which can be broken down through dielectrophoresis and electrochemical procedures. Therefore, the electric field plays an important role in the migration of leukocytes to high voltage areas. This is because different electrode arrangements produce varying electric field distributions. Furthermore, this study applied finite element methods to generate electric fields when electrodes with an AC voltage were applied to blood placed in a chamber. Therefore, in this study, variations of mediums and electrode arrangements were investigated, which led to the recommendation of 3 models. The objective was to investigate electrode arrangements that produce optimal electric field distribution for the three models to exhibit a booster of electric field distribution. The maximum electric field is generated close to the electrode (Z=2 mm and Z=92 mm) for any material (i.e. normal blood, B lymphocyte, and T lymphocyte) with values of 22.6 V/m and 23.47 V/m, 22.85 V/m and 22.97 V/m, and 24.88 V/m and 25.01 V/m. Based on principle, lymphocytes in the blood result in positive dielectrophoresis, since they migrate to a higher electric field close to the electrode, with enough input voltage to turn the electrochemical process on the leukocytes into electric current. Furthermore, this study provides new perspectives and ideas, which have not been revealed in previous studies on blood cancer therapy using the electric field of Ag electrode in blood cancer distribution. Keywords: blood cancer, dielectrophoresis, electric field, voltage, electrochemical, and cancer therapy.

The delivery of radiation therapy to patients requires prior planning made by medical physicists to achieve radiotherapy goals. Radiotherapy has a plan to eradicate the growth of cancer cells by giving high doses and minimizing the radiation dose to normal tissue. Evaluation of planning is generally done based on dosimetric parameters, such as minimum dose, maximum dose, and means dose obtained from the DVHs data. Based on the same DVHs, data were evaluate dinterms of biological effects to determine the highest possible toxicity in normal tissue after the tumor had been treated with radiation using the NTCP model. The evaluation was conducted by selecting three DICOM-RT data of post-mastectomy right breast cancer patients who had been prescribed a dose of 50 Gy obtained from the Hospital MRCCC Siloam Semanggi database. All data were processed using open-source software DICOManTX to get the DVH and isodose information. Matlab-based CERR software was used to calculate the NTCP model. The results show that the three patients' DVH and isodose treatment planning result in a homogeneous dose distribution result because the PTV area obtains adose limit of ≥ 95%. Moreover, normalt issue still gets adose below the tolerance limit based on the standard from RTOG 1005 and ICRU 83. Analysis of NTCP shows a complication probability below 1% for each organ, suggesting that any organ which has been irradiated has a low likelihood of complications. Therefore, it can be concluded that the treatment planning which has been made in the three patients using the IMRT technique has achieved the objectives of radiotherapy, which is to minimize toxicity to healthy organs. Keywords: DVH, isodose, NTCP, radiotherapy.

Rural development is a social process. It involves local community in all stages of development. Community dialog is a means for facilitating community involvement in determining a development direction, potential development plan and development sus-tainability in the future. Frequently, local community is considered as the development target. This position puts them just being development watchers, spectators, silent and passive recipients. Moreover, these silent roles make them remain unempowered since they do not know how to determine their future, how to take part in collective decision and feel being neglected. This study examines potentials of community involvement in dialog. A qualitative research paradigm is adopted. The data are collected byrecording, transcribing and analyzing community dialog at Klagen, Nganjuk, Jawa Timur. The study finds that community dialog offers considerable potentials. The first potential of community dialog is generating local community commitment, awareness, sense of belongingness and supportive character to build their own homeland. These positive development psychological states,characters and ethos are soft human dimensions which can be critical drivers in rural development. The second is creation of local knowledge and scientific knowledge joint enabling innovation and collective learning process. This joint-knowledge allows the combination of local wisdom and scientific insight. The third is building shared or collective development vision and plan. This plan and vision allow the development prioritizing process and development of rural strength, potential competitive advantage and resource building. The fourth is expanding rural networking and exercising rural people capacity to build wider internal and external social relationship.

Introduction: This study aimed to evaluate the efficacy of a synthesized bolus in the reduction of damage to body tissues and the protection of the organ at risk (OAR) in radiotherapy application. Several properties of the synthesized bolus, including density, transmission factor, and effective mass attenuation coefficient, were investigated. Material and Methods: The materials used comprising of propylene glycol (PG), silicone rubber (SR), and aluminum (Al). The dimension of the synthesized bolus was measured using an acrylic case with a size of 11×11 cm² and thickness sizes of 0.5, 1, and 1.5 cm. Furthermore, the boluses were irradiated by linear accelerator with the photon beam energies of 6 and 10 MV, using linier accelerator (LINAC) Varian 2300ix. Results: In this research,the density of synthesized bolus was evaluated by mass per volume equation. The results showed that the density of bolus was similar to the density of tissue/water, fat, and air. . Furthermore the bolus with the composition of PG 24%, SR 8%, and Al 1.5% of all energies, transmission factors of 0.978 and 0.984, thickness of 1.5 cm, and effective mass attenuation coefficients of 0.0144 and 0.0107 cm²/g had the closest properties to the body tissues in terms of dosimetry characterization. Conclusion: The results revealed that the synthesized bolus could increase the percentage surface dose, reduce skin-sparing effect, and protect OAR. The findings indicated that the synthesized bolus had a potential application in clinical therapy.

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.

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.

Introduction: The study aimed to analyze and determine impact of the 3D-CRT fractionation on risk of secondary cancer. Material and Methods: This study used a patient-specific anthropomorphic phantom, and radiation was performed using the Three Dimensional-Conformal Radiation Therapy Field in Field (3D-CRT FinF) technique with conventional, hypofractionation, and hyperfractionation with a dose of 200 cGy, 260 cGy, and 160 cGy in 25, 16, and 30 fractions respectively. It focused on the contralateral breast, contralateral lung, and ipsilateral lung as Organs at Risk (OAR). In addition, the Dose Volume Histogram (DVH) value, normal tissue complication probability (NTCP), and risk of secondary cancer were evaluated. Results: The results showed that the average dose value (Dmean) for ipsilateral lung with hypofractionation was smaller than conventional and hyperfractionation of 1519.8, 1826.7, and 1753.6 cGy, respectively. Furthermore, hypofractionation also reduced radiobiological effects by 50% in the ipsilateral lung with an NTCP value of 0.01% compared to conventional and hyperfractionation with a value of 0.02%. Hypofractionation reduces the risk of secondary cancer in the contralateral breast, contralateral lung, and ipsilateral lung by 16.38, 17, and 22.31% compared to conventional fractionation and 12.75, 13.54, and 21.34% compared to hyperfractionation, respectively. Conclusion: The dose profiles in OAR was smaller in treatment planning with hypofractionation. EBT3 film verification results showed that the ipsilateral lung received more doses than planned, with an insignificant difference (p>0.05). In radiobiology, the ipsilateral lung has the highest probability of complications in treatment planning with conventional fractionation and hyperfractionation. [ABSTRACT FROM AUTHOR]

Ag and AgNO film were fabricated through sputter deposition on indium tin oxide (ITO) conductive glass. Electrochemical detection using cyclic voltammetry (CV) was carried out for low albumin levels in blood as a parameter of cancer patients. This study aims to determinate low albumin level as a biomarker cancer. Albumin adsorption on the Agfilm/ITO and AgNOfilm/ITO was also investigated to determine the level of sensitivity of both electrodes. Analysis of the CV measurements indicated that the Agfilm/ITO electrode was more sensitive compared to the AgNOfilm/ITO electrode, with a sensitivity value of 4.564 µA M-1cm-2 for the Agfilm/ITO electrode and 2.123 µA M-1cm-2 for the AgNOfilm/ITO electrode. The testing of albumin levels in blood within a range of low concentration levels between 10-1 and 10-8 g/dL indicated a detection limit of 10-9 g/mL. The selectivity of Ag electrodes was found to be very good for other interfering molecules such as urine, glucose, and lysozyme. The results of the modeling of electric field and magnetic field distribution showed that the Agfilm/ITO electrode possessed larger values than the AgNOfilm/ITO electrode. From this analysis, it can be concluded that the electrode modified with micro-sized Ag achieved more effective results than the electrode modified with AgNO. This sensor can determine low albumin level as a blood cancer biomarker. This sensor holds great promise for use in real samples in the future. [ABSTRACT FROM AUTHOR]

Electrical impedance tomography (EIT), as a non-ionizing tomography method, has been widely used in various fields of application, such as engineering and medical fields. This study applies an iterative process to reconstruct EIT images using the simultaneous algebraic reconstruction technique (SART) algorithm combined with K-means clustering. The reconstruction started with defining the finite element method (FEM) model and filtering the measurement data with a Butterworth low-pass filter. The next step is solving the inverse problem in the EIT case with the SART algorithm. The results of the SART algorithm approach were classified using the K-means clustering and thresholding. The reconstruction results were evaluated with the peak signal noise ratio (PSNR), structural similarity indices (SSIM), and normalized root mean square error (NRMSE). They were compared with the one-step gauss-newton (GN) and total variation regularization based on iteratively reweighted least-squares (TV-IRLS) methods. The evaluation shows that the average PSNR and SSIM of the proposed reconstruction method are the highest of the other methods, each being 24.24 and 0.94; meanwhile, the average NRMSE value is the lowest, which is 0.04. The performance evaluation also shows that the proposed method is faster than the other methods. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to evaluate the efficacy of a synthesized bolus in the reduction of damage to body tissues and the protection of the organ at risk (OAR) in radiotherapy application. Several properties of the synthesized bolus, including density, transmission factor, and effective mass attenuation coefficient, were investigated. Material and Methods: The materials used comprising of propylene glycol (PG), silicone rubber (SR), and aluminum (Al). The dimension of the synthesized bolus was measured using an acrylic case with a size of 11×11 cm² and thickness sizes of 0.5, 1, and 1.5 cm. Furthermore, the boluses were irradiated by linear accelerator with the photon beam energies of 6 and 10 MV, using linier accelerator (LINAC) Varian 2300ix. Results: In this research, the density of synthesized bolus was evaluated by mass per volume equation. The results showed that the density of bolus was similar to the density of tissue/water, fat, and air. Furthermore the bolus with the composition of PG 24%, SR 8%, and Al 1.5% of all energies, transmission factors of 0.978 and 0.984, thickness of 1.5 cm, and effective mass attenuation coefficients of 0.0144 and 0.0107 cm²/g had the closest properties to the body tissues in terms of dosimetry characterization. Conclusion: The results revealed that the synthesized bolus could increase the percentage surface dose, reduce skin-sparing effect, and protect OAR. The findings indicated that the synthesized bolus had a potential application in clinical therapy. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the capability of Ageratum conyzoides and Mikania micrantha extracts to synthesize silver nanoparticles (AgNPs) and their antibacterial capability against gram‐positive and gram‐negative bacteria. Several properties of the synthesized AgNPs, including plasmonic, biomolecule bonding, shape, size, and antibacterial, were investigated. Ultraviolet–visible (UV–vis) spectroscopy was employed for characterizing their plasmonic properties. Functional groups on the produced AgNPs were investigated by Fourier‐transform infrared (FT‐IR) spectroscopy. The size and shape of the AgNPs were identified using the field‐emission scanning electron microscopy (FESEM). Inhibition zone measurement was carried out for evaluating the antibacterial capability. This study showed that the extracts of A. conyzoides and M. micrantha were able reducing agents as evidenced by the formation of the spherical AgNPs. UV–vis spectroscopy, FT‐IR spectroscopy, and FESEM confirmed the physicochemical characteristics of AgNPs. AgNPs that were synthesized using M. micrantha were slightly smaller than those produced using A. conyzoides. In general, the present work establishes that the synthesized AgNPs have antibacterial capability depending on their size and synthesis procedure. [ABSTRACT FROM AUTHOR]

Performance of microstrip compact antenna with slope thickness of substrate was analyzed using FD-TD Method and was tested experimentally. The whole antenna size is 100 mm x 100 mm x 2 mm using dielectric substrates 3.4. The proposed antenna was fabricated based on PCB-FR4 (Printed Circuit Board) using the photolithography process. The simulation and experimental results are compared in their characteristics. The novelty in this paper is the difference of the substrate width; the variation of the substrate width is 1h, 3h, and 5h with a value of h is 1.6 mm. The proposed antenna has two resonance frequency on 1.2 GHz and 2.4 GHz range. The novelty in this research is the change in the shape of the dielectric taper design causes a frequency shift, change in impedance values, and patterns of polarization. The addition of the substrate geometry antenna causes the antenna resonance frequency shifts to a lower frequency range; the first resonant frequency shifted from 1.41 GHz to 1.3 GHz and the second resonance frequency shift of 2.66 GHz to 2.43 GHz. Value of the impedance on that range for 5h width is 80.1-45.2i Ohm, so the proposed antenna has capacitive characteristic more than width 1h and 3h. Besides the addition of the substrate thickness can affect the shape changes from linear polarization to circular polarization. [ABSTRACT FROM AUTHOR]

Electrical Impedance Tomography (EIT) isa non-invasive medical imaging technique which estimates the electrical impedance distribution within tissue. The basic principle of EIT isa mapping of the immittance distribution (tomography) usingthe measurement of some passive electrical properties of tissue named bioimpedance.The study aimed to assess the performance of the EIT system in detectingan anomaly in thorax imaging with varying different frequencies, by analysis of sensitivity distribution. Sensitivity distribution was visualized using COMSOL Multiphysics simulation in a human thorax represented as an elliptic cylinder phantom consisting ofan inhomogeneous medium within and without an anomaly represented by a sphere. Current density distribution was collected for sensitivity analysis using the neighboring method with current injection at 1 mA for each pair of electrodes with frequencies 70, 100, and 130 kHz. Results indicate that the modeled two dimensional- EIT detected changes in the inhomogeneous media with and without anomaly inside the modeled thorax phantom very well. [ABSTRACT FROM AUTHOR]