bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unipolar arc plasmas on nanostructured tungsten surfaces under perpendicular magnetic field
Authors: Hwangbo Dogyun , Nishijima Daisuke , Kajita Shin , Doerner Russell P , Ohno Noriyasu 
Published: November 2020

Abstract
Unipolar arcing is an important phenomenon in terms of wall erosion and the subsequent plasma contamination in nuclear fusion devices. In this study, unipolar arc plasmas are experimentally explored under the presence of the external magnetic field perpendicular to a tungsten (W) sample on which a ‘fuzz’ nanostructure surface is formed. It is found that the fuzz layer thickness, d
fuzz, plays a dominant role in determining the motion of arc spots, the arc ignition probability, and arc plasma parameters. High-speed imaging reveals that the motion of arc spots becomes more collective, as d
fuzz increases. Interestingly, arc spots make a circle while moving outward. With increasing d
fuzz, the amount of eroded W atoms increases, as indicated from an observed increase in the total visible emission intensity, while the arc ignition probability is found to drop. The physical mechanisms are discussed, in detail, based on spectroscopic measurements of the electron temperature, obtained from Boltzmann plots of both W I and W II, and the electron density, determined from Stark broadening of W I lines.
Evaluation of Cd1–x
Zn
x
S as electron transport layer in superstrate and inverted configurations of Sb2Se3 solar cells with n-i-p structure
Authors: Ayala-Mató F , Vigil-Galán O , Seuret-Jiménez D , Courel Maykel , Fernández Susana 
Published: November 2020

Abstract
In this work, we evaluate the role of the ternary compound, Cd1–x
Zn
x
S, as an electron-transport layer (ETL) in the n-i-p structure of antimony selenide (Sb2Se3) solar cells. The incorporation of Zn reduces the amount of Cd and contributes to improving the power-conversion efficiency of the solar cell. On the other hand, the n-i-p structure makes it possible to overcome two issues that impair the efficiency of Sb2Se3 solar cells: the potential barrier due to the rear contact and the low hole concentration in the Sb2Se3 absorber material. In this paper, we present a theoretical work on Sb2Se3 solar cells using the SCAPS 1-D software. The theoretical analysis allows us to understand the impact of the semiconductor parameters on efficiency and also to find the optimal values for an optimized device. The optimal molar composition of the ternary compound is investigated in the superstrate and inverted configurations. Parameters such as the thickness, defect density, and the acceptor concentration of the Cd1–x
Zn
x
S and Sb2Se3 layers are optimized. Also, we analyze the impact of interface-defect density at the hole-transport layer (HTL) (Sb2Se3) and the ETL (Sb2Se3). Following optimization, a power-conversion efficiency (η) of 14.29% is obtained using Cd0.4Zn0.6S as the ETL and Cu2O as the HTL in the superstrate configuration. This simulation process is expected to guide other experimentalists in the design and manufacture of solar cells.
Network-based brain–computer interfaces: principles and applications
Authors: Gonzalez-Astudillo Juliana , Cattai Tiziana , Bassignana Giulia , Corsi Marie-Constance , De Vico Fallani Fabrizio 
Published: November 2020

AbstractBrain–computer interfaces (BCIs) make possible to interact with the external environment by decoding the mental intention of individuals. BCIs can therefore be used to address basic neuroscience questions but also to unlock a variety of applications from exoskeleton control to neurofeedback rehabilitation. In general, BCI usability depends on the ability to comprehensively characterize brain functioning and correctly identify the user’s mental state. To this end, much of the efforts have focused on improving the classification algorithms taking into account localized brain activities as input features. Despite considerable improvement BCI performance is still unstable and, as a matter of fact, current features represent oversimplified descriptors of brain functioning. In the last decade, growing evidence has shown that the brain works as a networked system composed of multiple specialized and spatially distributed areas that dynamically integrate information. While more complex, looking at how remote brain regions functionally interact represents a grounded alternative to better describe brain functioning. Thanks to recent advances in network science, i.e. a modern field that draws on graph theory, statistical mechanics, data mining and inferential modeling, scientists have now powerful means to characterize complex brain networks derived from neuroimaging data. Notably, summary features can be extracted from brain networks to quantitatively measure specific organizational properties across a variety of topological scales. In this topical review, we aim to provide the state-of-the-art supporting the development of a network theoretic approach as a promising tool for understanding BCIs and improve usability.
Multi-dimensional persistent feature analysis identifies connectivity patterns of resting-state brain networks in Alzheimer’s disease
Authors: Li Jin , Bian Chenyuan , Luo Haoran , Chen Dandan , Cao Luolong , Liang Hong 
Published: November 2020

Abstract

Objective. The characterization of functional brain network is crucial to understanding the neural mechanisms associated with Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Some studies have shown that graph theoretical analysis could reveal changes of the disease-related brain networks by thresholding edge weights. But the choice of threshold depends on ambiguous cognitive conditions, which leads to the lack of interpretability. Recently, persistent homology (PH) was proposed to record the persistence of topological features of networks across every possible thresholds, reporting a higher sensitivity than graph theoretical features in detecting network-level biomarkers of AD. However, most research on PH focused on zero-dimensional features (persistence of connected components) reflecting the intrinsic topology of the brain network, rather than one-dimensional features (persistence of cycles) with an interesting neurobiological communication pattern. Our aim is to explore the multi-dimensional persistent features of brain networks in the AD and MCI patients, and further to capture valuable brain connectivity patterns. Approach. We characterized the change rate of the connected component numbers across graph filtration using the functional derivative curves, and examined the persistence landscapes that vectorize the persistence of cycle structures. After that, the multi-dimensional persistent features were validated in disease identification using a K-nearest neighbor algorithm. Furthermore, a connectivity pattern mining framework was designed to capture the disease-specific brain structures. Main results. We found that the multi-dimensional persistent features can identify statistical group differences, quantify subject-level distances, and yield disease-specific connectivity patterns. Relatively high classification accuracies were received when compared with graph theoretical features. Significance. This work represents a conceptual bridge linking complex brain network analysis and computational topology. Our results can be beneficial for providing a complementary objective opinion to the clinical diagnosis of neurodegenerative diseases.
Experimental studies of plasma-antenna coupling with the JET Alfvén Eigenmode Active Diagnostic
Authors: Tinguely R.A. , Puglia P.G. , Fil N. , Dowson S. , Porkolab M. , Dvornova A. , Fasoli A. , Fitzgerald M. , Guillemot V. , Huysmans G.T.A. , Maslov M. , Sharapov S. , Testa D. , contributors JET 
Published: November 2020

Abstract
This paper presents a dedicated study of plasma-antenna (PA) coupling with the Alfvén Eigenmode Active Diagnostic (AEAD) in JET. Stable AEs and their resonant frequencies f, damping rates γ < 0, and toroidal mode numbers n are measured for various PA separations and limiter versus X-point magnetic configurations. Two stable AEs are observed to be resonantly excited at distinct low and high frequencies in limiter plasmas. The values of f and n do not vary with PA separation. However, |γ| increases with PA separation for the low-f, but not high-f, mode, yet this may be due to slightly different edge conditions. The high-f AE is detected throughout the transition from limiter to X-point configuration, though its damping rate increases; the low-f mode, on the other hand, becomes unidentifiable. The linear, resistive MHD code CASTOR is used to simulate the frequency scan of an AEAD-like external antenna. For the limiter pulses, the high-f mode is determined to be an n = 0 GAE, while the low-f mode is likely an n = 2 TAE. During the transition from limiter to X-point configuration, CASTOR indicates that n = 1 and 2 EAEs are excited in the edge gap. These results extend previous experimental studies in JET and Alcator C-Mod; validate the computational work performed by Dvornova et al (2020 Phys. Plasmas
27 012507); and provide guidance for the optimization of PA coupling in upcoming JET energetic particle experiments, for which the AEAD will aim to identify the contribution of alpha particles to AE drive during the DT campaign.
Structural and Morphological Properties of Undoped and Manganese Doped Hematite Nanoparticles Prepared by Ball Milling Method
Authors: Hadianto Heri , Amiruddin Erwin , Venera Rebi Septiawan Putri , Aprilia Vivi 
Published: November 2020

Abstract
Hematite nanoparticles of undoped and manganese doped were synthesized from natural sand of Logas District Kuansing Regency Riau Province by ball milling method. Structural and morphological properties of these compounds were studied using X-Ray Diffractometer (XRD) and Scanning electron microscope (SEM) respectively. Crystalline structure, lattice parameters, morphologies of the synthesized compounds were studied and the results are discussed. X-ray diffraction (XRD) confirmed the presence of a hematite (α-Fe2O3) phase. Average crystallite size based on flections (1 0 4) for undoped and manganese doped magnetic iron oxide particles are 39.2 nm and 38.2 respectively. The intensity of (1 0 4) reflection is stronger for magnetic iron oxide synthesized for 60 hours than that of 2 step (60+60) hours ball milling. This indicates the product grown along (1 0 4) direction. The average crystallite size decreases when magnetic iron oxide is doped with 10% Mn as confirmed by SEM images.
Effect of Vegetation Profile and Air Data Rate on Packet Loss Performance of LoRa E32-30dBm 433 MHz as a Wireless Data Transmission
Authors: Wiyadi Eri , Setiadi Rahmondia Nanda , Umar Lazuardi 
Published: November 2020

Abstract
Internet of Things (IoT) communication network is currently one of the rapidly expanding uses a technology called the Long Range (LoRa) module using unlicensed industrial, scientific, and medical (ISM) radio frequencies. For sensor data transmission, the propagation depends on many parameters, such as transmit power, antenna, and vegetation obstacles on the propagation path. This work presents a 30 dBm LoRa E32-433T30D module of 433 MHz used for biosensor data transmission. LoRa performance testing was carried out in obstacle-dense areas (NLoS) of the Tempuling forest Riau that varies the distance parameters, and the programmable transmission speed (ADR) ranges from 1.2 Kbps to 9.2 Kbps. Results show that the higher the ADR value, the shorter the signal range, which is represented by the increase of the packet loss number. The highest ADR value is 19.2 Kbps signal coverage is only able to cover a distance of 1.4 Km with a data loss number of 86 %, while for 1.2 Kbps experiences a data loss of 20 % at a distance of 2 Km. The highest signal strength RSSI value was obtained at -67 dBm at a distance of 200 m and the lowest at -102 dBm at a distance of 2 Km. The decrease in RSSI value is caused by attenuation and signal interference from the obstacle height that exceeds the height of the antenna.
Preparation of Iron Oxide Magnetic Nanoparticles Natural Sand of Rokan River Synthesis with Ball Milling
Authors: Salomo S. , Erwin A. , Usman M. , Muhammad H. , Nita Y. , Linda W. 
Published: November 2020

Abstract
Natural sand samples taken from the Rokan river, Riau Province, Indonesia, have been ball milled for 100 (one hundred) hours using a ball with a diameter of 1.5 cm and a constant rotation angular velocity of the tube of 100 revolutions / minute. Neodymium Iron Boron (NdFeB) strong magnets are used to separate magnetic minerals from their non-magnetic minerals. Magnetic induction was measured using the Pasco PS-2162 probe and its value was used to calculate the magnitude of magnetic susceptibility, it turns out that the magnetic susceptibility value of the 100-hour Ball Milling results increased significantly when compared to the magnetic susceptibility before Ball Milling, 968,245x 10−5 becomes 19.471x 10−5. The results of the X-Ray Fluorescence (XRF) test showed that the percentage of Fe milled increased from 1.669% to 35.187%, the particle size obtained from the scanning electron microscope (SEM) results was in the nanometer order of 78 nm and the X-Ray Difractometer (XRD) results.) shows that the magnetic nanoparticles produced are dominated by the hematite phase (α-Fe2O3) and the others are in the magnetite (Fe3O4) phase..
Isolation of Antibiotic-Producing Bacteria from Extreme Microhabitates in Mangrove Ecosystem
Authors: Effendi Irwan , Tanjung Afrizal , Sari Desy Mutia 
Published: November 2020

Abstract
This study aims to isolate and identify the antibiotic-producing bacteria from extreme microhabitates in the marine ecosystem against fish pathogenic bacteria (V. alginolyticus, A. hydrophila, dan Pseudomonas sp). Microbes from samples were grown on NA and TSA media. Well grown colonies were examined for their ability to produce antibiotics against the pathogens by the streaking and paperdisc diffusion method on MHA. Potential isolates were identified through a series of phenotypic and genotypic test. A number of 4 antibiotic-producing bacteria were selected. DNA of the bacteria were extracted using DNA easy mini column and amplified by using Kappa PCR kit with 16S rDNA 1A and 16S rDNA2A primers. The PCR results were analyzed on a 1.5% agarose gel in Tris-acetat-EDTA (TAE) electrophoresisuffer (4 mM Tris-acetate and 1 mM disodium EDTA at pH 8.0). The electrophoresis process was carried out at 60 mA (100-120 v) for 30-45 minutes read by UV Transilluminator. Isolate Ni5 have a 99% homological similarity to Bacillus amyloliquefaciens strain SH20. Bacterial isolate Xy3 has a 100% homological similarity with Bacillus cereus strain NY180. Isolate S11 has a 97% homological similarity with Enterobacter hormaechei strain CGAPGPBBS-064. Isolate K22 has a 99% homological resemblance to Klebsiella pneumoniae strain MW-W 754.
Thermal Inactivation of Eupenicillium Javanicum Ascospores in Pineapple Juice: Effect of Temperature, Soluble Solids and Spore Age
Authors: Evelyn  , Chairul  , Muria S R , Adella L , Ramadhani R 
Published: November 2020

Abstract
Food spoilage leading to food waste and substantial economic losses is a major issue for the food industry. The spoilage is often due to bacterial and fungal contamination in foods. Spores from microorganism pose a great concern since they can survive pasteurization and grow in specific foods. The obj1ectives of this work were to investigate the effect of temperature (T: 80-90°C), soluble solid concentration (11–20°Brix), and spore age (30–60 days) on the log reductions of Eupenicillium javanicum ascospores in pineapple juice. It was also carried out to estimate the first-order kinetic parameters (D and z-values) from the log survivor curves. Increasing the temperature from 80 to 90°C for 10 min increased the spore inactivation in 11°Brix pineapple juice by 6.4 log. For 5-log inactivation, increasing the percentage weight (% wt.) of sucrose from 11°Brix to 20°Brix at 90°C, increased the time needed to inactivate the spores by 2.6 min. Likewise, increasing the age of ascopores from 30 days to 60 days, also increased the time required by 16.7 min. The estimated D-values for 30-days old spores in 11°Brix juices were 19.84 min at 80°C, 4.99 min at 85°C and 1.45 min at 90°C, with z-values of 8.6-8.8°C. The results obtained provide useful data to design and predict pasteurization process targeting E. javanicum ascospores.
Some structural patterns of the stand of Scotch pine (Pinussylvestris L.) in the conditions of Zavolzhsky - ObshchySyrt province
Authors: Rjabuchina M.V. , Ryabinina Z.N. , Kalyakina R.G. , Gerasimenko V.V. , Maiski R.A. 
Published: November 2020

Abstract
Under the structure of stands is understood the order of combination and the nature of the relationship of the trees that make them up according to the main taxation characteristics, both in statics and dynamics.Since the stand is an unified system where the growth and development of trees are closely interconnected, the study of the structure should be carried out for the entire set of trees without separating any of its constituent parts, as indicated by N.V. Tretyakov.A.A. Makarenko proposed a methodology for studying the structure of stands, based on the construction of distribution curves for 10 classes within the range of variation of taxation features.In the present work, it was found that the distribution of actual values within 9 or 11 steps does not significantly affect the statistics of the distribution series calculated on the same trial plots for 10 classes, and with an increase or decrease in the classes, the difference between these statistics will increase accordingly.
Morphological Variation of Castor Bean (Ricinus communis L.) on Peatland Area in Kepulauan Meranti Riau Indonesia
Authors: Wahibah Ninik Nihayatul , Fitmawati  , Yahya Vanda Julita , Perdana Muhammad Agung , Budiono Rahmat 
Published: November 2020

Abstract
Castor (Ricinus communis L.) has been reported as source of raw material for various products, including biofuel, cosmetic and pharmaceutical industries. This plant is known as an adaptive plant which perform well-growth and development in unfertile soil. We observed that castor plants grow and develop in Kepulauan Meranti, Riau Province, Indonesia where peatland mostly dominates. Objective of the study was to evaluate genetic diversity of castor bean germplasm in Kepulauan Meranti grown in fired-peatland area based on morphological characters. Sampled plants were tagged and parts of plant were photographed and characterized. Some plant organs such as leaves and fruits were taken for more identification. We observed 12 castor accessions showing distinctive phenotypes. Morphological characters that varied among genotypes were plant architecture; stem anthocyanin; stem wax; stem color; adaxial leaf surface; fruit wax; form of racemic; main seed coloration; secondary coloration of seed; and type of secondary coloration of seed. All genotypes showed prickle existence on fruit surface. The result indicates that castor germplasm in Kepulauan Meranti serve diverse genetic variability. Further studies including assessment based on agronomic, biochemical and molecular approaches are still required for supporting castor breeding program to develop new cultivars particularly that adaptive to peat soil area.
Antidiabetic Activity of Triterpenoids from Anisophyllea disticha
Authors: Fikriyah Miftahul , Almurdani Muhammad , Eryanti Yum , Teruna Hilwan Y. 
Published: November 2020

Abstract
Diabetes and its complication are strongly associated with mortality and morbidity rate in Indonesia. The number of diabetes patients is expected to increase every year. α-Glucosidase enzyme inhibitor widely used for treatment of diabetes. It may be obtained by isolation of Indonesian medicinal plants. As medicinal plant which is used by Talang Mamak tribe, Rakit Kulim, Indragiri Hulu, Riau, Anisophyllea disticha has its own attraction to study because its potential secondary metabolites have never been reported scientifically. Therefore, this study aims to determine antidiabetic activity by α-glucosidase inhibition method of metabolites this plant. The isolation of metabolites was based on solvent polarity fractionation by vacuum liquid chromatography method on ethyl acetate extract. Chemical structures of the metabolites were elucidated based on spectroscopic characteristics, included FTIR and 1D H-NMR. The isolated compounds were assumed to be two triterpene derivatives. The IC50 of compound 1, compound 2, and acarbose as a positive control were 46.246 ± 0.166, 80.273 ± 0.08 and 19.737 ± 0.046, respectively. Therefore it can be concluded that both compounds have potential as antidiabetic.
Transesterification of Crude Palm Oil (CPO) to Biodiesel Using Heterogeneous Catalyst K-CaO from Anadara Granosa Synthesized by Sol Gel Method
Authors: Maisarah  , Nurhayati  , Linggawati Amilia 
Published: November 2020

Abstract
This study aimed to synthesize biodiesel from CPO using heterogeneous K-CaO catalyst from blood cockle (anadara granosa) shells. The catalyst was synthesized by sol gel method with variation calcination temperatures of 700, 800 and 900°C. The catalyst was characterized using X Rays Diffraction (XRD) and X-Ray fluorescence (XRF). The XRD results showed the presence of mineral lime, portlandite and calcite. Based on the XRF results that K-CaO heterogeneous catalyst contained 96,538% of calcium oxide (CaO). Biodiesel was synthesized by transesterification reaction with variations in time conditions (1, 2, 3 and 4 hours) and reaction temperature (50, 55, 60 and 65°C). The maximum biodiesel yield of transesterification reaction using heterogeneous K-CaO catalyst from blood cockle shell (anadara granosa) was 92,648% using catalyst calcination at a temperature of 700 °C and the optimum reaction time was 2 hours using 3% (w/w) catalyst, mol ratio of oil: methanol 1:6, stirring speed of 500 rpm and reaction temperature of 60 °C.
Biomass Extraction as Green Corrosion Inhibitor for Low Carbon Steel in Hydrochloric Acid Solution
Authors: Komalasari  , Zultiniar  , Karim Abdul Rahman Marwis , Susanto Reno , Azhari Ilman , Utami Syelvia Putri , Heltina Desi 
Published: November 2020

Abstract
Corrosion is a degradation of metals quality caused by a chemical reaction between a metal and its ambient. The use of a green inhibitor is a natural method to control the corrosion rate of the metal. The objective of this research is to count the efficiency of the green inhibitor from biomass of tea and coffee extract, to find which variable that affect the most of corrosion rate of carbon steel, to determine the best concentration of extracts to control the corrosion rate of carbon steel. The extraction methods are the use method with a solvent ratio 1:4 of ethanol : aqua dest. Weight loss method is used to determine the rate of corrosion with 0,5g/L, 1g/L, and 1,5 g/L variance of inhibitor concentrations and 3, 6, 9, and 12 days immersed times. The lowest corrosion rate is 61,27 mpy at 1,5 g/l of tea extract inhibitor solution with 9 days immersed times and the highest efficiency is 79,02% at 1,5 g/l of tea extract inhibitor solution with 12 days of immersed times.