Advances in Science and Technology Vol. 126

Abstract: Medical visualization requires interdisciplinary groups of researchers to analyze and explore medical data. Visualizing medical data can use open-source visualization software to avoid administration effort in medical visualization collaboration works. Visualization Toolkits (VTK) is a free, open source for medical visualization. VTK has been used to reconstruct medical images. However, few studies have used VTK to visualize DICOM data from Computed Tomography (CT) scan images using local hospital data in Indonesia. This study aims to reconstruct DICOM data from CT scan of the local hospital in Kupang city, Province Nusa Tenggara Timur, Indonesia. We used VTK to visualize the CT scan images of the head, thorax, and abdomen into two-dimensional (2D) and three-dimensional (3D) images. The DICOM data was visualized first in 2D, and then it was reconstructed into 3D using ray casting and volume rendering algorithm on VTK 8.2. The VTK was built on C++ and Visual Studio 2017. We have successfully demonstrated VTK to visualize 2D and 3D CT scan data from the local hospital in Kupang city. In the future, VTK has the potential to be used by a group of researchers using local hospital data in Indonesia to visualize 2D and 3D CT scan images.

Abstract: The high number of dengue fever in Indonesia is a severe problem that affects the health of the Indonesian people. Coupled with the pandemic conditions that limit all movements of various groups due to social distancing, starting from health volunteers who must serve the community related to Covid-19. Routine inspection of mosquito larvae in every household must still be conducted to avoid the breeding of these mosquito larvae. Thus, an automatic and independent mosquito larva recognition system is needed from images taken via mobile devices that make it easier for each family head to identify areas of the home environment whether there are mosquito larvae or not. This paper proposes a new approach to larva recognition using convolutional neural network based on the TensorFlow library. The TensorFlow Serving and TensorFlow Lite were evaluated to get the best model with limited memory so that it can be used on mobile devices. The system classifies photo images into 2 labels, namely larvae or not. The result of this system is the presence or absence of mosquito larvae from the image. The TensorFlow Serving model produces an average testing accuracy of 96.1%, which is better than TensorFlow Lite of 90.1% in testing various conditions. The developed convolution neural network model produces a better model than the previous method.

Abstract: The need for data on marine resources is increasing, Indonesia as one of the world's maritime countries plays a big role in this. The successful application of big data on marine resources is not only seen from the technology used in it but it is also must related to other system components. A qualitative approach is used in this study to produce a big data model that can be applied to marine resources. This research produces a big data model from the perspective of a Knowledge Management System (KMS) which consists of four elements or layers, namely organization, Big Data Process and Technology Information, and people as users. The integration of these four elements is expected to promote economic transformation and knowledge in the marine and fishery sectors.

Abstract: In this work, urethane dimethacrylate (UDMA) was used as dental resin as an non-toxic alternative to Bisphenol A-glycidyl methacrylate (Bis-GMA). Additionally, UDMA combine with triethylene glycol dimethacrylate (TEGDMA) monomer with various concentration ratio, meanwhile camphorquinone (CQ) and diphenyl-(2,4,6-trimethylbenzoyl) phosphine (TPO) as photoinitiator. First, UDMA:TEGDMA with ratio of 40:60, 50:50, 60:40, 70:30 and 80:20 wt.% was prepared. Second, the solution was ultrasonic for 15 min with introduction of CQ and TPO (1:2 wt%). Third, irradiation of UV LED with wavelength of 375 nm for 2 min to initiate polymerization reaction of monomers. Scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA) and mechanical properties were used to investigate the morphology, chemical bonding of polymerization reaction, decomposition temperature and tensile strength. Based on our findings, we found that that UDMA:TEGDMA ratio of 50:50 wt% demonstrates uniform and smooth surface, high degree of conversion, and good mechanical strength, which is promising for dental resin.

Abstract: A Research has been carried out on the manufacture and characterization of Polyvinyl Alcohol (PVA)/Chitosan composite nanofiber membranes using electrospinning technique which addressed for wound dressing and antibacterial efficacy. The electrospun composite nanofiber membranes were made with various volume ratios of PVA:Chitosan, namely 1:9, 2:8, and 3:7, which were named P9K1, P8K2, and P7K3 respectively. The electrospinning was performed at a voltage of 10 kV, the distance between the nozzle tip to the collector was 10 cm, a flow rate of 1 µl/h, at room temperature, a relative humidity (RH) of around 63%, and the spinning time was 3 h. Their physical and chemical were characterized by FTIR, SEM, DMA (dynamic analytical analysis), and antibacterial activity. These characterization results indicated that adding chitosan greatly affects the quality of the nanofiber membranes formed and their potential applications. The addition of chitosan produced nanofiber membranes with a larger diameter, shorter fibers, and more beads and droplets. The functional groups in the nanofiber membranes experienced a wavenumber shifting and increased transmittance which was relatively high compared to pure PVA nanofiber membrane (P10K0). Only the P8K2 met the standard for medical materials, with UTS and PTP of 2.73 MPa and 19.03% respectively. Also, it had antibacterial efficacy against E.coli and S. aureus of 16.90% and 8.87% respectively.

Abstract: – The research on CPO as an insulator to replace mineral oil. The CPO was heated using vacuum distillation technology. The parameters used are the temperature of 110°C to 170°C with the difference of 10°C and the vacuum pressure of 0 mmHg to-600 mmHg with the difference of 200 mmHg. The highest breakdown voltage measurement of 49 kV (170°C-600 mmHg), the lowest viscosity is 20 mPas (170°C-600 mmHg), the lowest water content was obtained at 30 (160°C-400 mmHg). The vacuum pressure and temperature rise causes the high breakdown voltage and viscosity are high and the water content is low. The relationship between vacuum pressure and breakdown voltage is y = 5.8 x + 7 with R² of 0.9397, the viscosity is y = -2x + 35.67 with R² of 0.9231 and the water content is y=-7.25x2 + 22.95x + 106.75 with R² of 0.9945.

Abstract: Amylase is essential in the industrial sector, but there are some challenges with its low reusability efficiency. The catalytic activity of the amylase can be affected by using an activated carbon matrix as an immobilization technique. In this study, we characterized the purified amylase of Aspergillus niger ICP2 and immobilized it to activated carbon. Amylase production from A. niger ICP2 was performed throughout a 7-day incubation. After partial purification, two amylase fractions were generated, including 90% saturation ammonium sulfate precipitation, a 10-kDa hollow fiber dialysis column, and anion exchange chromatography. Thin-layer chromatography analysis showed the presence of glucose in fractions I and II, indicating glucoamylase activity. Both fractions had optimum pH and temperatures at 4.5 and 70°C, respectively. Fraction I was stable at acidic pH (3.5-5), while the stability of fraction II was in the range of acid to base (4-7.5) after incubation for 1 hour at 37°C. Both fractions displayed the same pattern of temperature stability (30-50°C) when incubated for 1 hour at optimum buffer. Activated carbon was used to immobilize amylase fraction II, which demonstrated the ability to hydrolysis the starch up to five times with a reduction in the activity of 50.4%. These results showed promising hydrolysis reusability by amylase immobilized using activated carbon.

Abstract: The future applications of amylase have sparked the interest of several industries, resulting in the discovery of possible amylase-producing microbes. Aspergillus niger ICP2 was an indigenous fungus isolated from coffee pulp that shows amylolytic activity after growing on a soluble starch agar. In this study, we optimized the production and successfully purified the amylase from Aspergillus niger ICP2. Amylase optimization production was performed for a 7-day of incubation under submerged fermentation. The amylase activity was measured using the iodin method, and the total protein was quantified spectrophotometrically at 280 nm. Purifying amylase crude extract conducted such as ammonium sulfate precipitation, dialysis, and anion-exchange chromatography. Amylase was maximally precipitated at 90% saturation, followed by dialysis on a 10 kDa column, increasing specific activity up to 12.17 U/mg and purity multiples of 9.31 times. Two peaks of amylase activity were formed when the dialyzed amylase was loaded onto anion exchange chromatography with specific activities of 14.47 U/mg (fraction I) and 32.73 U/mg (fraction II). The increase in specific activity and purity fold indicated that the amylase purification process was successful.

Abstract: Zeolite Pahae an adsorbent material by activating physical and chemical processes has been synthesized. The methods used are ball milling and coprecipitation methods. Zeolite was ball milling and activated, then sieved using 100 mesh and 200 mesh sieves. To obtain nanozeolite, a ball mill and coprecipitation were carried out to obtain a size of 9.08 nm. The X-Ray Diffraction (XRD) results showed that the zeolite structure is tetragonal. Zeolite is used as a heavy metal adsorbent. Atomic Absorption Spectroscopy (AAS) method can determine how much zeolite can absorb heavy metals. The results of the AAS test showed that the absorption of nanozeolite to heavy metals was Pb of 99.81%; Fe is 99.99% and Mn is 96.87%. The absorption of 200 mesh zeolite is Pb of 99.45%; Fe is 99.99% and Mn is 99.61%. The absorption of 100 mesh zeolite is Pb of 99.66%; Fe is 99.98%, and Mn is 99.68%. From these results obtained zeolite particle size affects the absorption of heavy metals.

Abstract: Hydroponic is a farming method that utilizes water, minerals, and oxygen. This study aims to find out the best nutrition towards growing curly lettuce (Lactuca sativa L.) by using the NFT (nutrient film technique) hydroponic system integrated with sensors to measure EC concentration of nutrients, pH acidity, and RH air humidity. This study also incorporates a grouped randomized design with two nutritional treatment (code P1 and P2), with 20 replication. The results showed that nutrition P1 producing a better variable compared to nutrition P2 in terms of plant length, quantity of leaves, length of root, total mass of fresh plants, total mass of plant crown, total mass of fresh roots, and chlorophyl content. Key words: NFT hydroponic system, nutrition, curly lettuce