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Food safety is a critical issue in ensuring public health, especially in preventing contamination from harmful substances illegally added to food. One such hazardous additive is borax, which is sometimes used by unscrupulous food producers to preserve texture and shelf life, despite its known toxicity and prohibition in food products. This study aims to detect the presence of borax in tofu, a widely consumed protein source, by utilizing two analytical tools such as a Texture Analyzer and a Spectrometer. The Texture Analyzer was employed to evaluate the physical firmness of tofu, as borax is known to increase its hardness. The Spectrometer was used to confirm the chemical presence of borax. Results indicated that tofu samples containing borax showed significantly firmer textures compared to control samples, and the spectrometric analysis successfully detected borax compounds. These findings demonstrate that both instruments are effective in identifying borax contamination. The study recommends the sustainable development of rapid and accurate detection methods for other hazardous additives to enhance food safety monitoring and enforcement practices.

A stable and accurate navigation system is crucial for the operation of Autonomous Underwater Vehicles (AUVs), especially in underwater environments where GPS signals are unavailable. This study aims to enhance AUV navigation performance by optimizing the use of a low-cost inertial sensor, the MPU6050, through calibration and signal processing techniques. The methodology includes reading raw data from accelerometer and gyroscope sensors, performing static calibration to reduce bias and noise, applying Fast Fourier Transform (FFT) for signal analysis, and implementing digital filters such as low-pass and high-pass filters. The raw data reveal significant deviations due to gyroscope bias and accelerometer noise. Static calibration effectively reduces systematic errors, although residual biases remain. FFT analysis identifies dominant frequency components in each axis, while digital filtering helps eliminate irrelevant frequency noise. Precision testing demonstrates that the sensor produces relatively stable data post-calibration, with the Z-axis showing higher deviation compared to the X and Y axes. The combination of calibration and signal processing methods significantly improves the data quality and reliability of the MPU6050 sensor. This research contributes to the development of more efficient and low-cost AUV navigation systems and supports the broader application of simple IMU sensors in underwater exploration and maritime technologies.

Cyanidin-3-glucoside (C3G) is a flavonoid compound that is an antioxidant and natural colorant widely found in berries and vegetables such as red cabbage. This study aims to explore the structural stability of C3G using computer simulations based on force field theory through Avogadro software. In this study, the Universal Force Field (UFF), Merck Molecular Force Field (MMFF94), and General Amber Force Field (GAFF) methods were used to analyze the stability of C3G. The energy optimization results showed that the Ghemical method produced a more stable structure than other methods, although there was a discrepancy with GAFF. The GAFF method was more stable than UFF, but required more energy to achieve stability. Overall, the difference in force field methods affected the molecule's stability through optimization energy and structure parameterization variations, which affected the distance and angle of atomic bonds. These findings provide an efficient picture of the stable conformation of C3G, which can be applied in the food, health, and cosmetic industries.

An increasing of public attention to the quality of food has been increasing, recently. One type of food that consumed is quail eggs (QE). In this study, QE were tested by Electrochemical Impedance Spectroscopy (EIS) method with some parameters such as complex impedance, dielectric constant, and loss tangent analysis. Several interesting results showed that dielectric properties of QE experience a fluctuation phenomenon if the test is influenced by storage duration, qualitatively. Therefore, we approximately prove that QE quality can be tested via EIS to obtain fine results.

As optical properties, the ultraviolet-visible (UV-Vis) absorption spectra of capsanthin-based red natural dye are a decisive parameter for their usage in various applications. Thus, accurately predicting the maximum UV-Vis wavelength (Amax) values is critical in designing dye-conjugated material. Extensive metadynamics simulations were carried out to generate capsanthin conformers at various levels of the extended tight-binding method. Benchmarking the time-dependent density functional theory (TD-DFT) methods help understand the results of a particular functional and allows a comparison between results obtained with different functional. The long-range correction (LC) scheme in LC-TD-DFT-D4/?B97X/def2-SVP has been found to reproduce the experimental Amax, and exhibited the effect of conformational changes to the calculated wavelengths. On the other hand, an inexpensive yet efficient LC-TD-DFTB method reproduced the experimental ?(max) insensitive to conformational changes.

The exponential increase in carbonaceous-based research has prompted the scientific community to apply it to numerous value-added applications. This paper aimed to systematically analyze the comprehensive contributions clusters of publications per year, country, institution, authors, and keywords-wise by using a quantitative review technique called bibliometric analysis. The data was retrieved from the Scopus database to identify the overall scientific trend results with the keyword "carbon dots as a sensor" from 2010 to 2020. The VOSviewer, WordItOut, and Datawrapper are selected as tools for bibliometric analysis and data visualization. In this work, the total citations from the Scopus Core Set and the total citations in the most recent year have only been used for the assessment of highly cited papers. The results showed that after 2014, the number of publications increased significantly with the work related to “carbon dots as sensors.” Thus, comprehensive journals like the Angewandte Chemie - International Edition were the most popular in publishing articles, contributing to almost 6.39% of the research area. The country-wise analysis revealed that China accounted for more than 67.18% of the articles published, followed by the United States and India, comprising 6.24% and 6.13%, respectively. Lastly, keyword cluster analysis revealed five major research hotspots for future discussion. Thus, this analysis provides an important starting point for further studies on research concerning the direction of "carbon dots as a sensor" for positive development in the research area.

The abundance of applications of alginates in aqueous surroundings created by their interactions with water is a fascinating area of research. In this paper, computational analysis was used to evaluate the conformation, hydrogen bond network, and stabilities for putative intermolecular interactions between alginate dimers and water molecules. Two structural forms of alginate (alginic acid, alg, and sodium alginate, SA) were evaluated for their interactions with water molecules. The density functional theory (DFT-D3) method at the B3LYP functional and the basis set 6-31++G** was chosen for calculating the data. Hydrogen bonds were formed in the Alg-(H₂O)_n complexes, while the SA-(H₂O)_n complexes showed an increase in Van der Walls interactions and hydrogen bonds. Moreover, in the SA-(H₂O)_n complexes, metal-nonmetal bonds existed between the sodium atom in SA and the oxygen atom in water (Na…O). All computational data in this study demonstrated that alginate dimers and water molecules had moderate to high levels of interaction, giving more stability to their complex structure.

This systematic literature review aims to study the thermal properties (TP) of poly(acrylic acid)-based hydrogels (PAA) by differential scanning calorimetry. The data sources were obtained from Google Scholar via Publish or Perish software from 2018 to 2020. The synthesis results show that most of the analysis of TP in PAA-based hydrogel consists of glass transition temperature ([ ]), melting temperature ([ ]), and enthalpy ([ ]). The subsequent thermal properties analysis is important for a new development and depth study in the future application.

The determination of residual stresses is of great importance for many threated metal applications. In this work, the XRD residual stress analysis was used to characterized tempered aluminum-based specimen 6082T with rotation angles (phi) 0°, 45° and 90°, respectively. Highest stress levels were found in the rolling direction (phi = 0°), while negligible along transfers direction (phi = 90°). In addition, a shear stress along rolling and transverse direction, and also the present of texture along (110) can be observed.