In the screening experiments for porcine pancreatic α-amylase inhibitors in 18 plants obtained from Indonesia, a potent inhibitory activity was detected in the extract of leaves of Abrus precatorius. ...The enzyme assay-guided fractionation of the extract led to the isolation of a triterpene ketone, lupenone (1), as a potent α-amylase inhibitor, together with 24-methylenecycloartenone (2) and luteolin (3). The mode of inhibition of compound 1 against porcine pancreatic α-amylase was a mixed inhibition. This is the first report that describes the potent α-amylase inhibitory activity of the low-polar triterpene ketone similar to compound 1. A comparison of the activities of the isolate and related compounds indicated the importance of C-3 ketone and the lupane skeleton in the α-amylase inhibitory activity.
Bali and Lombok islands are popular resorts and tourist destinations in the world because of their culture and beautiful natural view. The natural and anthropogenic radionuclides content in surface ...air of Bali and Lombok islands such as 226Ra, 232Th, 40K and 137Cs were measured at 3 monitoring stations in a period from January to December 2016. Aerosol samples were collected using a high volume total suspended particles (TSP) sampler. The activity concentrations of those radionuclides in airborne particulate matter were measured using gamma-ray spectrometry. The results show that the activity concentrations of natural radionuclides 226Ra, 232Th, and 40K ranged from 1.0 to 3.04 µBq/m3, not detected to 1.78 µBq/m3, and 0.03 to 0.49 mBq/m3, respectively. All airborne particulate matter filter samples were found to be lower than the minimum detectable activity for 137Cs, which means that none of 137Cs is originated from atmospheric nuclear weapon test and other sources in surface air of Bali and Lombok islands. Variations of monthly activity concentrations of natural radionuclides were influenced by rainfall during study period. Furthermore, the peak concentrations of radionuclides also occur due to volcanic ash coming from Mount Rinjani eruption.
This paper proposes a novel technique of adaptive switching alternative median (ASAM) filter for high-density white spot noise removal. The ASAM filter is composed of two blocks filtering, namely ...main and secondary block filtering, respectively. The proposed secondary block filtering is a new technique in high-density impulse noise removal and the main contribution of this research. The ASAM algorithm was tested on the standard 8-bit gray-scale, 512×512 pixel Lena image and a real neutron radiographic image. The results showed significant reduction of white spot noise in both types of images through visual inspection. To measure the performance of noise removal in simulation test we measured the peak signal-to-noise ratio (PSNR), structural similarity (SSIM) index, and denoising time, and in real application tests we measured signal-to-noise ratio (SNR). From the experiments of simulation test, at the highest level noise of 95 % the obtained PSNR and SSIM are 23.584 dB and 0.696 respectively. These are higher than the results of other algorithms that are 16.697 dB and 0.475, respectively, for DBA, 16.696 dB and 0.408 for NAFSM, and 18.860 dB and 0.568 for NASNLM. The denoising times for DBA, NAFSM, NASNLM, and ASAM were obtained as 6.469 s, 5.186 s, 36.735 s, and 5.197 s respectively. From the experiments of real application test we obtained the SNR for DBA, NAFSM, NASNLM, and ASAM as 32.42 dB, 6.01 dB, 18.77 dB, and 32.96 dB, respectively. In general, these results show that ASAM filter is superior to the existing filtering methods. The ASAM filter improved the image restoration quality, especially in removing the high-density white spot noise, and was able to yield good filtering result which exhibits better PSNR, SSIM, denoising time, and qualitative visual inspection.
Abstract
Particulate Matter or aerosol is associated with climate change and global warming through the effect called radiative forcing. Biomass burning aerosol consists of Black Carbon, which has a ...positive radiative forcing that warms the atmosphere. The goal of this study is to ascertain biomass burning in Sumatera Island’s effect on aerosol concentration. We used Particulate Matter with diameter less than 10 µm (PM
10
) concentration in the near equator Global Atmosphere Watch Bukit Kototabang (GAW-BKT) and biomass burning in Sumatera Island from Visible Infrared Imaging Radiometer Suite (VIIRS) hotspot count. The statistical and spatial analysis was done for 2014-2018, which include the severe 2015 biomass-burning season. From the analysis of PM
10
concentration and hotspot (R
2
=0.85) and air mass trajectories, biomass burning in Sumatera is the source of PM
10
in GAW-BKT. Statistical analysis showed that hotspot in Sumatera, as well as PM10 concentration, follows a monsoonal pattern where the 90
th
percentile of the hotspot and PM
10
concentration fell on dry season. The seasonal variabilities of particulates suggest the strong contribution of biomass open burning which occurred annually with different intensities.
The World Tourism Organization (UNWTO) in 2014 released that there are 28 million visitors who visit Russia. Most of the visitors might have problem in typing Russian word when using digital ...dictionary. This is caused by the letters, called Cyrillic that used by the Russian and the countries around it, have different shape than Latin letters. The visitors might not familiar with Cyrillic. This research proposes an alternative way to input the Cyrillic words. Instead of typing the Cyrillic words directly, camera can be used to capture image of the words as input. The captured image is cropped, then several pre-processing steps are applied such as noise filtering, binary image processing, segmentation and thinning. Next, the feature extraction process is applied to the image. Cyrillic letters recognition in the image is done by utilizing Self-Organizing Map (SOM) algorithm. SOM successfully recognizes 89.09% Cyrillic letters from the computer-generated images. On the other hand, SOM successfully recognizes 88.89% Cyrillic letters from the image captured by the smartphone's camera. For the word recognition, SOM successfully recognized 292 words and partially recognized 58 words from the image captured by the smartphone's camera. Therefore, the accuracy of the word recognition using SOM is 83.42%
The minimum requirement of green space area is about 30% of the urban area. The green space area of Jakarta is around 12% and Palembang, 20%. This condition can cause air pollution to increase ...especially for a certain parameter (PM). The objective of this study is to predict spatial dispersion of PM less than 10 microns (PM10) of ambient air in Jakarta and Palembang. Spatial dispersion prediction is done using wind rose diagram from the dominant wind direction. The study has continued with the prediction of PM10 sources based on the city's overlaid map with the pollution rose diagram. The PM10 sources of Jakarta have been predicted from road and soil dust while Palembang are predicted from road dust, soil dust, transportation, industrial emission and smoke from fire. The dominant wind direction of Jakarta and Palembang are east-southeast (dry season) and west-northwest (rainy season) which correlates with the seasonal winds.
The disclosure of a company's social responsibility (CSR) showed how much the company has a motive for its environmental welfare; a company that has high responsibility prevents violations that have ...a negative impact on their environment, including tax evasion. This study aims to examine the effect of CSR disclosure on tax avoidance and test the GCG component, audit committee and independent commissioners in moderating the effect of CSR on tax avoidance. The study population was manufacturing companies listed on the Indonesia Stock Exchange in 2012-2015. Samples were obtained using a purposive sampling method with 108 samples. This research is quantitative research. The research test uses multiple regressions, such as goodness of fit test and hypothesis test. This study provides evidence that there is a positive influence between CSR on tax avoidance, besides that the audit committee as a moderating variable weakens the positive influence of CSR on tax avoidance, but independent commissioners are not proven as moderating variables between the effects of CSR towards tax avoidance.
Rooted phylogenetic networks are rooted acyclic digraphs. They are used to model complex evolution where hybridization, recombination, and other reticulation events play a role. A rigorous definition ...of network compression is introduced on the basis of recent studies of relationships between cluster, tree, and rooted phylogenetic networks. The concept reveals new connections between well-studied network classes, including tree-child networks and reticulation-visible networks. It also enables us to define a new class of networks for which the cluster containment problem is solvable in linear time.
Food delivery system is one kind of geographical information systems (GIS) that can be applied through digitation process. The main case in food delivery system is the way to determine the shortest ...path and food delivery vehicle movement tracking. Therefore, to make sure that the digitation process of food delivery system can be applied efficiently, it is needed to add shortest path determination facility and food delivery vehicle tracking. This research uses A Star (A*) algorithm for determining shortest path and location-based system (LBS) programming for moving food delivery vehicle object tracking. According to this research, it is generated the integrated system that can be used by food delivery driver, customer, and administrator in terms of simplifying the food delivery system. Through the application of shortest path and the tracking of moving vehicle, thus the application of food delivery system in the scope of geographical information system (GIS) can be executed.
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