bluuebunny/crossref_metadata_2025 huggingface dataset:
An improved design for e-mode AlGaN/GaN HEMT with gate stack β-Ga2O3/p-GaN structure
Authors: Ge Mei , Li Yi , Zhu Youhua , Chen Dunjun , Wang Zhiliang , Tan Shuxin
Published: July 2021

To improve the performance of the conventional p-GaN gate AlGaN/GaN high electron mobility transistors (HEMTs), we propose an improved design for e-mode AlGaN/GaN HEMT with a gate stack β-Ga2O3/p-GaN structure. The simulated results show that the proposed device increases the threshold voltage and the gate breakdown voltage in comparison with the conventional p-GaN gate HEMT due to the use of the β-Ga2O3 layer, which has an additional β-Ga2O3/p-GaN heterojunction and decreases the strength of electric field in the gate region. Moreover, the proposed device exhibits a lower off-state leakage current, which can be attributed to the less donor ionized density. In addition, the impacts of the β-Ga2O3 layer thickness are investigated. There is a trade-off between β-Ga2O3 layer thickness and the performance of the proposed device, including threshold voltage, gate breakdown, and saturation drain current.
High-performance reverse blocking p-GaN HEMTs with recessed Schottky and p-GaN isolation blocks drain
Authors: Wang Haiyong , Mao Wei , Zhao Shenglei , Gao Beiluan , Du Ming , Zheng Xuefeng , Wang Chong , Zhang Chunfu , Zhang Jincheng , Hao Yue
Published: July 2021

In this Letter, the p-GaN high electron mobility transistor (HEMT) with hybrid drain of recessed Schottky (RS) and p-GaN isolation blocks' drain (HSP drain) is proposed and fabricated for good reverse blocking capability. The related operation mechanism has been investigated and revealed. The proposed device features a drain terminal consisting of the array-distributed recessed Schottky and p-GaN isolation blocks. Based on the features, the reverse leakage current (5 × 10−9 A/mm at VDS = −100 V) is obviously reduced by two orders of magnitude compared with that (5 × 10−7 A/mm) of p-GaN HEMTs only with recessed Schottky (RS) drain, which is the lowest leakage current among the reported GaN-on-Si reverse blocking transistors. The introduction of these p-GaN isolation blocks has a negligible impact on Von (Von = 0.63 V). Therefore, a good improvement in the trade-off between the reverse leakage current and Von could be achieved because of the significant reduction in the reverse leakage current without sacrificing Von. In addition, the reverse breakdown voltage of −800 V at 1 μA/mm with a substrate grounded in the proposed device is evidently improved compared with the counterpart (−680 V), which is attributed to effective alleviation of the high electric field near the HSP drain. These results demonstrate the significance and potential of p-GaN HEMTs with HSP drain in reverse blocking applications.
Selective properties of diffusive couplings and their influence on spatiotemporal chaos
Authors: Shabunin A.
Published: July 2021

Spatiotemporal chaos in a ring of logistic maps with symmetric diffusive couplings is investigated in dependence on the coupling strength. Spatial spectrum of oscillations is compared with the wave response of a linear spatial filter formed by couplings between maps in the ensemble. Correlation between the spectrum and the filter’s amplitude–wave characteristics is considered.
Tonal noise of voluteless centrifugal fan generated by turbulence stemming from upstream inlet gap
Authors: Ottersten M. , Yao H.-D. , Davidson L.
Published: July 2021

Volutes for radial-flow turbomachines (e.g., centrifugal fans and pumps) are spiral funnel-shaped casings that house rotors. Their function is to guide the flow from rotors to outlets and maintain constant flow speeds. Under specific conditions, however, volutes are removed (termed voluteless) to reduce flow losses and noise. In this paper, a generic voluteless centrifugal fan is investigated for the tonal noise generation at an off-design operation point. In contrast to typical tonal noise sources induced by the fan blades, we find out that another predominant source is the turbulence stemming from the clearance gap between the fan front shroud and the inlet duct. The turbulence evolves along with the front shroud and is swept downstream to interact with the top side of the blade leading edge. An obvious additional tone is observed at 273 Hz other than the blade passing frequency (BPF0) and relevant harmonic frequencies. By coarsening the mesh resolution near the inlet gap and front shroud in the simulations, we artificially deactivate the gap turbulence. Consequently, the tone at 273 Hz disappears completely. The finding indicates that the interaction between the gap turbulence and blades accounts for the tone. As the gap turbulence exists near the front shroud, this rotating wall introduces rotational momentum into the turbulence due to skin friction. Hence, this tonal interaction frequency is smaller than BPF0 with a decrement of the fan rotation frequency. To the authors' knowledge, this is the first time that voluteless centrifugal fans are studied for the gap-turbulence noise generation.
Energy harvesting from passive oscillation of inverted foil
Authors: Alam Md. Mahbub , Chao Li-Ming , Rehman Shafiqur , Ji Chunning , Wang Hanfeng
Published: July 2021

A numerical study is carried out to investigate the energy harvesting from an inverted foil undergoing flow-induced pitching oscillation for reduced velocity Ur  =  1–45 and damping ratio ζ = 0–0.295. The benchmark results with undamped foil (ζ = 0) indicate that the foil does not oscillate for Ur  ≤ 27 but does oscillate with increasing amplitude for 27 < Ur < 34 and with constant amplitude for Ur  ≥ 34. Lissajous diagrams of moment coefficient against the foil displacement are linked to the energy harvesting, showing how Ur and ζ affect the oscillating amplitude, reduced frequency, wake structures, and power exchange between the foil and the flow. The energy harvesting efficiency η up to 15.06% is achieved at Ur  =  37 and ζ = 0.130 with a reduced frequency f* = 0.151 that is used by the cruising aquatic animals. The foil oscillation with negative power enhances the growth of vortices while that with positive power weakens the growth.
Construction and evolution of knotted vortex tubes in incompressible Schrödinger flow
Authors: Tao Rui , Ren Hongxiang , Tong Yunjin , Xiong Shiying
Published: July 2021

We propose a theoretical method for constructing an initial two-component wave function that can be transformed into a knotted velocity field with finite kinetic energy and enstrophy. The wave function is constructed using two complex-valued polynomials, with one determining the desired shape of the knotted central axis and the other encoding the twisting nature of vortex lines, which facilitates the study of helicity conversions. We construct six knotted vortex fields with various centerline and twist helicity as initial conditions for direct numerical simulation of incompressible Schrödinger flow (ISF) in a periodic box. Although the evolution of morphological structure is similar for ISF and classical viscous flow, with all the knots becoming untied after a short time to form one or more separate vortex rings, their statistics are quite different. During the critical period of vortex reconnection, the increase in enstrophy is much more moderate in ISF than in viscous flow, indicating that the Landau–Lifshitz term in ISF inhibits the energy cascade from large to small scales. We also find that the centerline helicity changes dramatically during reconnection, which is consistent with the evolution of the geometrical shape of vortex lines.
Crystal orientation dependence of deep level spectra in proton irradiated bulk β-Ga2O3
Authors: Polyakov A. Y. , Smirnov N. B. , Shchemerov I. V. , Vasilev A. A. , Kochkova A. I. , Chernykh A. V. , Lagov P. B. , Pavlov Yu. S. , Stolbunov V. S. , Kulevoy T. V. , Borzykh I. V. , Lee In-Hwan , Ren Fan , Pearton S. J.
Published: July 2021

The effects of 20 MeV proton irradiation with fluences of 5 × 1014 and 1015 p/cm2 on electrical properties of lightly Sn doped n-type (net donor concentration 3 × 1017 cm−3) bulk β-Ga2O3 samples with (010) and (−201) orientation were studied. Proton irradiation decreases the net donor density with a removal rate close to 200 cm−1 for both orientations and similar to the electron removal rates in lightly Si doped β-Ga2O3 epilayers. The main deep electron traps introduced in the β-Ga2O3 crystals of both orientations are near Ec−0.45 eV, while in Si doped films, the dominant centers were the so-called E2* (Ec−0.75 eV) and E3 (Ec−0.1 eV) traps. Deep acceptor spectra in our bulk –Ga2O3(Sn) crystals were dominated by the well-known centers with an optical ionization energy of near 2.3 eV, often attributed to split Ga vacancies. These deep acceptors are present in a higher concentration and are introduced by protons at a higher rate for the (010) orientation. Another important difference between the two orientations is the introduction in the surface region (∼0.1 μm from the surface) of the (010) of a very high density of deep acceptors with a level near Ec−0.27 eV, not observed in high densities in the (−201) orientation or in Si doped epitaxial layers. The presence of these traps gives rise to a very pronounced hysteresis in the low temperature forward current–voltage characteristics of the (010) samples. These results are yet another indication of a significant impact of the orientation of the β-Ga2O3 crystals on their properties, in this case, after proton irradiation.
Protistan grazing impacts microbial communities and carbon cycling at deep-sea hydrothermal vents
Authors: Hu Sarah K. , Herrera Erica L. , Smith Amy R. , Pachiadaki Maria G. , Edgcomb Virginia P. , Sylva Sean P. , Chan Eric W. , Seewald Jeffrey S. , German Christopher R. , Huber Julie A.
Published: July 2021

Significance

Heterotrophic protists are ubiquitous in all aquatic ecosystems and represent an important ecological link in food webs by transferring organic carbon from primary producers to higher trophic levels. Here, we quantify the predator–prey trophic interaction among protistan grazers and microbial prey within hydrothermal vent fluids from the Gorda Ridge spreading center in the northeast Pacific Ocean. Estimates of protistan grazing pressure were highest at sites of diffusely venting fluids, which are an oasis of biological activity in the deep sea. Our findings suggest that elevated grazing activity is attributed to a diverse assemblage of heterotrophic protistan species drawn to the hydrothermal vent habitat and demonstrates the important ecological roles that protists play in the deep-sea carbon cycle.
Juvenile hormone regulation of microRNAs is mediated by E75 in the Dengue vector mosquitoAedes aegypti
Authors: Aksoy Emre , Raikhel Alexander S.
Published: July 2021

Significance

Aedes aegyptimosquitoes transmit numerous viral pathogens to humans. Targeting mosquito reproduction could be critical in controlling the spread of these pathogens. MicroRNAs (miRNAs) control key physiological processes during mosquito reproduction. The insect hormone juvenile hormone (JH) is essential for a mosquito to achieve reproductive competence. JH governs expression of several miRNAs through the transcription factor Ecdysone-induced protein 75 (E75-RD). Blocking E75 by RNA interference impairs miR-2940, which in turn affects ovarian follicle formation and egg maturation. We identified the messenger RNA of the glutamate receptor Clumsy as a miR-2940 target and showed its involvement in reproduction. This study establishes E75-RD to be an intermediate factor within the JH hierarchical network that is involved in regulation of miRNAs in mosquitoes.
Prevention and management of infections after exposure to ionising radiation
Authors: Maher Keri R , Bouligny Ian M , Yeager Andrew M
Published: July 2021

Ionising radiation impacts many organ systems, each of which comprises a level of immunity to infectious disease. Bone marrow toxicity after radiation results in a predisposition to leukopenia and subsequent susceptibility to bacterial, viral, and fungal infections. Radiation-induced damage to mucosal, integumentary, and solid organ structures disrupts additional lines of innate defense. Over the past three decades, much progress has been made in effective antimicrobial prophylaxis, resulting in decreased infectious complications and improved survival. Vaccination schedules following myeloablative radiation have become highly regimented and treatment of overt infectious complications is largely standardised. In this article, we discuss consequences, prevention, and management of infections following exposure to ionising radiation.
Characterization of OSL dosimeters used at the ELI-beamlines laser-driven accelerator facility
Authors: Cimmino A , Horváth D , Olšovcová V , Stránský V , Truneček R , Versaci R
Published: July 2021

The Extreme Light Infrastructure (ELI) Beamlines laser-driven accelerator facility is set to operate the most intense non-military laser system in the world, with ultra-high power up to 10 PW, concentrated plasma intensities of up to 1024 W cm−2, and ultra-short laser pulses of the order of few femtoseconds. A robust and redundant radiation monitoring system is in place to minimise risks to personnel and general public. Beryllium oxide optically stimulated luminescence (BeO-OSL) detectors are used to monitor radiation levels in the experimental building and surrounding grounds. In fact, in recent years, BeO-OSL have become an increasingly more popular choice for personal and environmental dosimetry. At ELI Beamlines, an exhaustive and thorough characterization process of the BeO-OSLs is in place. Dosimeter responses are studied as a function of delivered air kerma and photon energies. Calibration curves are calculated. Results from the latest calibration campaign are presented.
SNR study on Fourier single-pixel imaging
Authors: Li Rui , Hong Jiaying , Zhou Xi , Wang Chengming , Chen Zhengyu , He Bin , Hu Zhangwei , Zhang Ning , Li Qin , Xue Ping , Zhang Xiao
Published: July 2021

According to the properties of Fourier transform, Fourier single-pixel imaging uses the illumination lights with cosine distributions to obtain the Fourier spectrum of the object, and then apply the inverse Fourier transform to reconstruct the spatial information of the object. This technique does not require detector arrays, such as charge coupled device and has proven to be insensitive to distortion, which is a great improvement over traditional photography techniques. In this manuscript, we present a detailed analysis and discussion on the signal-to-noise ratio (SNR) of Fourier single-pixel imaging. Compared with conventional imaging whose SNR is independent of pixel number N, Fourier single-pixel imaging achieves an improved SNR which is up to N times as high as the dynamic range of detection. Furthermore, this SNR benefit is further confirmed experimentally, in cases of one dimension and two dimensions.
Superconductivity and electron–phonon interaction in Sr
x
Bi2Se3 under pressure
Authors: Li Mingtao , Fang Yifei , Kenney-Benson Curtis , Wang Lin
Published: July 2021

Pressure-induced superconductivity has been widely explored and observed in Bi2Se3-based topological materials to hunt for topological superconductors. Although their triggered superconductivity has a close connection to their pressure-induced structural phase transitions, the quest for the electron pairing mechanism of these superconducting semiconductors in both their initial rhombohedral and high-pressure phases remains unknown. In this work, we present a systematic study of the pressure effect on superconducting properties and lattice dynamics using a combination of electrical transport, Raman-scattering, and synchrotron x-ray diffraction measurements using diamond anvil cells. One key finding is our observation of a cooperative connection between the strength of the electron–phonon interaction (EPI) generated by optical branches and the pressure-tunable superconductivity in rhombohedral Sr
x
Bi2Se3 crystal. The underlying suppression mechanism of the T
c by pressure is ascribed to the weakening of the electrons’ interaction with the optical phonon modes in the rhombohedral phase. In the intermediate monoclinic phase, the T
c value underwent a sharp increase with carrier density accumulation accompanying the concurrent enhanced EPI. This is intuitively unusual since it is expected that the EPI shall be weakened by inducing more conducting carriers in a normal metal. In the tetragonal phase, the superconductivity is interpreted within BCS theory, since it is fully metallized and obeys the adiabatic Born–Oppenheimer approximation well. Our findings are important to fully understand unconventional superconductivity and the unusual pairing mechanism in the layered rhombohedral Bi2Se3-based superconductors.
Unified thermal model for photohadronic neutrino production in astrophysical sources
Authors: Fiorillo Damiano F.G. , van Vliet Arjen , Morisi Stefano , Winter Walter
Published: July 2021

High-energy astrophysical neutrino fluxes are, for many
applications, modeled as simple power laws as a function of
energy. While this is reasonable in the case of neutrino production
in hadronuclear pp sources, it typically does not capture the
behavior in photohadronic pγ sources: in that case, the
neutrino spectrum depends on the properties of the target photons
the cosmic rays collide with and on possible magnetic-field effects
on the secondary pions and muons. We show that the neutrino
production from known photohadronic sources can be reproduced by a
thermal (black-body) target-photon spectrum if one suitably adjusts
the temperature, thanks to multi-pion production processes. This
allows discussing neutrino production from most known pγ
sources, such as gamma-ray bursts, active galactic nuclei and tidal
disruption events, in terms of a few parameters. We apply this
thermal model to study the sensitivity of different classes of
neutrino telescopes to photohadronic sources: we classify the model
parameter space according to which experiment is most suitable for
detection of a specific source class and demonstrate that different
experiment classes, such as dense arrays, conventional neutrino
telescopes, or radio-detection experiments, cover different parts of
the parameter space. Since the model can also reproduce the flavor
and neutrino-antineutrino composition, we study the impact on the
track-to-shower ratio and the Glashow resonance.
Impact of Covid-19 pandemic on vegetable farmers in North Sumatra
Authors: Girsang Moral Abadi , Marpaung Imelda , Parhusip D , Haloho L , Tobing S P , Nainggolan P , Hidayat S
Published: July 2021

This research was conducted from June to August 2020 with the research locations were the two main vegetable producer regencies in North Sumatra, namely Karo Regency and Simalungun Regency. The purpose of this study was to determine the impact of the Covid-19 pandemic on the vegetable farmer’s income, to determine which factors most influenced vegetable farmer’s income during the pandemic, and to recommend policies to reduce the impact of the pandemic on vegetable farmers in North Sumatra. Data were collected through interviews with 53 vegetable farmers in two districts whose locations were selected purposively while the respondent farmers were selected by judgment. The data in this study were analyzed using descriptive methods through a quantitative approach. The results show that as many as 92.9% of respondents stated that their income had decreased during the Covid-19 pandemic. Factors causing a decrease in farmers income were rising prices for fertilizers and pesticides (89,3%), worries about activities due to the pandemic (98,2%), limited transportation for marketing among provinces (23,2%), regional transportation restrictions (46,4%), and time restrictions on selling in the market (26,8%), several government policies towards farmers during a pandemic must be implemented immediately.
Potential of non-timber forest products as medicinal plant sources in the protected forest area of Enrekang Regency
Authors: A R Rusmiati , Latifah H , Daud M , Hasanuddin  , Sultan
Published: July 2021

This study aims to determine the types of plants, parts and potential of medicinal plant sources in protected forest areas of Enrekang Regency. Data were collected through observation, interviews, questionnaires, surveys and literature studies, and grouped into primary and secondary. The results show that there were 12 types of medicinal plants in the protected forest, namely candlenut, breadfruit, cinnamon, balsam, patikala, siri, laruna, suren, guava, kapok, lime and coffee. Furthermore, the medicinal plant parts used include seeds, roots, stems, leaves, fruit, bark, sap and flowers. The community uses medicinal plants in 7 ways, specifically burning, mashing, frying, drying, boiling, kneading and processing. There were eight methods of how to use of medicinal plants by the community, namely applying, drinking, gargling, inhaling, placing them on the wound, eating directly and washing the eyes.
A review: Agricultural production and food industry during Pandemic COVID-19
Authors: Indah A B R , Sahar D P , Afifudin M T , Ikasari N , Mulyadi
Published: July 2021

During the Covid-19 pandemic, many sectors were affected, including the world economic sector, which had fallen sharply, leading to several countries experiencing recession. some businesses closed due to government restrictions. However, this is different from the food industry, which is required to continue producing to meet food needs during the Covid-19 pandemic. This is not in line with the production system that is being implemented because there are several obstacles related to the supply of raw materials for production and ensuring that the health level of workers is maintained during a pandemic. This is a challenge for the food industry, because on the one hand they have to meet the needs of consumers while the production system is hampered because it can be caused by an unusual division of working hours. Therefore, a literature study was conducted regarding the state of the food industry production system during the Covid-19 pandemic and examined several policies that could be taken to ensure that the food production system continues as expected and supports food security.
Nandong as a culture-based effort to overcome food security toward COVID-19 pandemic situation in Simeulue Island
Authors: Zulkarnain  , Lubis T , Ramlan  , Dardanila  , Hasrul S , Shaumiwaty  , Saputra N
Published: July 2021

This research discussed Oral Tradition Nandong (OTN) role through its performance of advice tradition in Simueluenese toward the agricultural sector. Further, it described how the performance supported food security during the lockdown period of the COVID-19 pandemic. The location of the research was on Simeulue Island. The data were collected by doing depth-interview and observation. The anthropolinguistic approach was used in this research. The research presented a model of food security in a rural area that deliberates both natural conditions and human effort. It showed that the role of OTN affected tenacity for surviving their food security as a concept. It was delivered through their daily activity and on some occasions. In those moments, the procedure in farming and cultivating are shared in a frame of advice. The obedience to obeying advice had affected Simeuluenese way of having access to sufficient food as their food security. This effort protected them from lack of food (especially the primary food) during lockdown situations caused by the COVID-19 pandemic. It can be concluded that OTN has an important role and should be accounted for in the agricultural sector for food security. Oral tradition as a medium to store and share knowledge and experiences built a cultural-based effort to maintain Simeuluenese agriculture for food security.
Utilization of liquid organic fertilizers from banana stems and coconut husk to increase potassium (K) in alfisols and corn
Authors: Riyandani R , Rasyid B , Baja S
Published: July 2021

The needs of plant potassium can be done by adding banana stem liquid organic fertilizer and coconut husk liquid organic fertilizer containing many K elements. This study aims to determine the increase in nutrient potassium and its effect on the growth of corn of Alfisols. The research design was a split-plot design consisting of the main plot as banana stem liquid organic fertilizer (P1) and coconut husk liquid organic fertilizer (P2). The sub-plots were d0 (0 ml), d2 (75 ml), d1 (50 ml), d3 (100 ml) obtained eight treatment combinations and repeated three times. Liquid organic fertilizer from banana stems and coconut husk can increase the availability of K in the soil. Coconut husk liquid organic fertilizer with 100 ml dose significantly affects the increase in pH, C-organic, Cation Exchange Capacity (CEC), availability of sodium, and exchangeable calcium. Also, it shows the highest average in increasing plant height and plant dry weight. The application of coconut husk liquid organic fertilizer significantly affects K content in plants and plant height. However, it has no effect on the dose given.
Agro-morphological variation of pigmented rice landraces from South Sulawesi grown in a temperate glasshouse of New Zealand
Authors: Hanifa A P , Millner J , McGill C , Sjahril R
Published: July 2021

The present study is aimed to compare the agro-morphological traits of 15 pigmented rice landraces and two modern rice varieties grown in the same environment. The selected rice were cultivated in a greenhouse of Massey University, New Zealand using a randomised complete block design with five replications. Data collection included agro-morphological observation and measurement. Quantitative data were analysed with analysis of variance, followed with Tukey HSD. Result showed considerable variability in seedling vigour, lodging, plant height, panicle exsertion, panicle thresh ability, spikelet fertility, and maturity among the studied pigmented rice landraces. Panicle exsertion and spikelet fertility indicate plant cope toward environmental change, which was performed better by many landraces than modern varieties. Variability in morphological characteristics was also recorded among tested varieties. Utilisation of the trait diversity can be useful for future breeding programs, which can lead to this crops’ improvement, including pest and disease resistance and grain quality research.
Potential and regeneration of tree species used as roosting habitat by Sulawesi fruit bats Acerodon celebensis in Jenetaesa, Maros Regency
Authors: Ruslan R K , Maulany R I , Nasri N , Ngakan P O
Published: July 2021

Sulawesi fruit bat (Acerodon celebensis) is an endemic fruit bat species of Sulawesi Island. Fruit bats have many important roles in the ecosystem where they act as seed dispersing agents, natural pollinating agents of flowering plants, and assist in forest regeneration. The purpose of this research is to determine their potential roosting tree species and their regeneration for A. celebensis in Jenetaesa, Maros Regency. This research was conducted for 3 months (May-July) in 2018 by initially identifying roosting tree species on the roosting site followed by surveying potential roost trees in 11.5 ha with the employment of 230 subplots. The results showed that in the area observed, the Sulawesi fruit bat has utilized 142 individuals of 21 tree species as roosting tree. Of 230 plots, there were a total of 234 individuals of 56 tree species found. However, based on species recorded to be used by the bats, only 56 individuals of 9 tree species and 11 bamboo clumps were found as potential roosting trees. Regeneration of A. celebensis roosting trees in an area of 11.5 ha was classified as low with only 7 species found and 32 individuals in average on each of growing stages.
Application of humic substances and bottom ash compounds in improving soil quality in limestone post-mining land
Authors: Musfira  , Jayadi M , Ahmad A
Published: July 2021

Limestone mining leaves the ex-mine land with poor soil chemical quality. Humic substances can be used as fertilizer to increase macronutrient availability in the soil and improve pH. The application of coal ash can improve the soil’s chemical, physical, and biological properties because it has a pH value, high organic C content, available P, and basic cations such as K, Na, Ca, and Mg. This research aims to determine the effect and interaction of humic substances and bottom ash interaction with different doses to improve soil quality after a limestone quarry. This research uses a randomized block design in a factorial pattern. This experiment consisted of humic substances (H) with 4 levels H0, H1 (0.09%), H2 (0.12%), and H3 (0.15%), and bottom ash (B) with three levels: B0, B1 (400 grams), B2 (600 grams). Humic substances at H2 concentration (0.15%) significantly increased C-organic, K, P-available, Mg-dd, and increased plant height. In contrast, bottom ash treatment at a B2 (600 grams) dose significantly affected the increase in C-organic, P-available, and Mg-dd. The treatment of humic substances with concentrations of H3 (0.15%) and bottom ash at a dose of 600 grams is the best interaction characterized by an increase in soil pH, CEC, Ca-dd, K, and Na. The application of a concentration of H3 (0.15%) and the provision of a dose of B2 (600 grams) or 120 tons/ha significantly affect the chemical properties of post-mining soils limestone and increase plant height.
Degradation of carbon stock (C) in calculation analysis of greenhouse gas emissions in cocoa plantations in South Sulawesi
Authors: Mustari K , Asrul L , Sultan I F
Published: July 2021

Cocoa as one of the most developed plantation commodities in Indonesia has a strategic position in efforts to increase carbon absorption to reduce the rate of global warming. As a woody plant, cocoa can absorb CO2 from the air and store it in the form of carbon (C) in its body (biomass). The absorption process of CO2 also affects the rate of photosynthesis in plants as the main ingredient in the breakdown of carbon in the plant body, especially cocoa. This research was conducted in Gantarangkeke District, Bantaeng Regency, South Sulawesi. Sampling was carried out by purposive sampling method on the basis of consideration of the type, density and cropping system applied. The estimation of biomass used a non-destructive method by measuring the diameter at breast height (DBH 1.3 m) and the height of the cocoa. Carbon storage in cocoa is differentiated by several plant ages, namely 5 years and 10 years. The results showed that the carbon stock in Bantaeng Regency was 27.05 tons/Ha.
Estimated carbon stock of various mangrove zonation in Marsegu Island, West Seram, Maluku
Authors: Irwanto  , Paembonan S A , Ngakan P O , Maulany R I
Published: July 2021

This study aimed to determine the amount of carbon storage of various mangrove zonation formed on Marsegu Island, West Seram, Maluku. Marsegu Island is a Raised Coral Island which has 46.75% mangrove vegetation (112.29 ha) with the area of each zonation is 32.12 ha (proximal zone), 39.00 ha (middle zone) and 41.17 ha (distal zone). The calculation of stored carbon stocks of various mangrove zonation in Marsegu island used SNI guidelines (Indonesian National Standard) 7724:2011. Field measurements for estimation of forest carbon stocks (ground-based forest carbon accounting). The estimations of above-ground carbon stored in the proximal zone, middle zone and distal zone are as follows: 52.11 t/ha, 70.50 t/ha and 140.13 t/ha. Meanwhile, the below-ground (root) carbon storage is 10.62 t/ha, 13.48 t/ha and 24.36 t/ha. The potential amount of carbon of above and below ground plus dead trees and dead-wood (necromass), with estimation soil carbon storage up to 20 cm depth, are 234.07 t/ha for the proximal zone, 317.47 t/ha for middle zone and 406.58 t/ha for the distal zone. The estimated total carbon stock in Mangrove Forest of Marsegu Island is 36,637.02 tonnes.
Effect of salt immersion, slaked lime immersion, and freezing on proximate and sensory of pineapple chip processed with vacuum frying
Authors: Marzuki S U , Khoshy D , Fardenan D , Haloho J D , Rahmayanti Ramli Andi
Published: July 2021

In this study, the effect of immersion of fresh pineapple in salt (NaCl) solution and slaked lime (Ca(OH)2) solution on quality and sensory of pineapple chip were investigated. A comparison of the freezing effect in each pre-treatment was also studied to decide the suitable recommendation of pineapple chip processing technology for Micro, Small and Medium Enterprises. The fresh pineapple slices were subjected to 1% w/v of salt solution and slaked lime solution for 30 minutes. To study the effect of freezing, the samples were frozen at -18°C for 24 hours. All samples were fried using a vacuum fryer at 70°C and 60 mmHg for 70 minutes. The study showed that immersion in salt solution resulting in the highest moisture and ash content (5.31±0.75°C and 2.03±0.23°C, respectively) while immersion in slaked lime solution gave the highest fat content (23.43±0.89°C). The freezing caused lower moisture and fat content but higher ash content in all treatments without significant differences (p ≤ 0.05). In sensory evaluation, immersion in salt solution resulting the highest likeability in taste, texture and overall acceptance with 5-scale hedonic test (4.10±0.85, 4.00±1.12, and 4.00±0.92, respectively) while freezing resulted in significantly (p ≥ 0.05) lower likeability in overall acceptance compared to the non-freezing treatment except for the immersion in a slaked lime solution.
The effect of processing methods on the quality of soy milk
Authors: Syamsuri R , Lestari S
Published: July 2021

The obstacle in the manufacture of soy milk is the beany flavour that derives from the soybean. Various soy milk processing technologies are used to eliminate the beany flavour, including soaking soybeans before grinding, peeling the soybean skin, heating, and giving them flavor. The objectives of this study were 1) to determine the protein content of soy milk by various processing methods; 2) to determine the level of consumer preference for soy milk by several processing methods and flavor variants. The results showed that the processing method using soybean skin and without hot water soaking had the highest soy milk protein content of 2.38%, while the lowest was in the processing method skinless soybean and hot water soaking of 1.73%. Organoleptic assays for color, aroma, viscosity, and taste parameters ranged from normal to liking for all treatments. For the parameter of beany flavor in soy milk, the control sample had the highest level. Organoleptically, giving coffee and chocolate flavor variants are proven to reduce the level of the beany flavor of soy milk.
The effect of the use of perkamen paper packaging on the shelf life estimation of Bolu Cukke using the Accelerated Shelf LifeTesting (ASLT) method
Authors: Latief R , Safitry E
Published: July 2021

This study aims to estimate the shelf life of Bolu Cukke packaged in parchment paper using the Accelerated Shelf Life Testing (ASLT) method. The critical water content parameters in Bolu Cukke are its aroma and its texture. The equilibrium moisture content was obtained from six types of saturated salt solution in the humidity chamber with 7-84% RH. Isothermal sorption curves are obtained by plotting Aw with equilibrium moisture content (Me) which would be tested using five isothermal sorption equation designs to obtain the Mean Relative Deviation (MRD) value. The lowest MRD value is 9.2 obtained from Hasley’s Isothermal equation design. All variables were then collected using the Labuza equation. The results of this study indicated that the estimation of shelf life of Bolu Cukke products in the parchment paper packaging at 30°C with 78% RH is approximately 7 days.
Characteristics of instant rice in several corn varieties
Authors: Layuk P , Salamba H , Lintang M , Karouw S , Abdullah N
Published: July 2021

The research aimed to process corn kernels into instant corn rice. Corn kernels are ground into grits then pre-gelatinized by churning for 25 minutes at a temperature of 85-93 0C with a ratio of grits and water (1: 4) then dried to become instant corn rice. The results showed that pre-gelatinization had an effect on yield and product characteristics such as bulk density, porosity, water absorption rate, dehydration and growth rate. The highest yield of instant corn rice was Manado Kuning at 89%. Cook time ranges from 7-10 minutes and the development rate is 110-130%. Types of varieties and duration of freezing affect the characteristics of instant corn rice. Freezing time increases bulk density, porosity, swelling rate and reduces rehydration ratio and water absorption rate. The best treatment was the Manado Kuning corn variety with a freezing time of 48 hours resulting in the highest bulk density, porosity and dehydration level where the bulk density met US standards for parboiled rice, which was between 0.40 to 0.42 g/ml.
Development and validation of spectrophotometric methods for quantitative determination of total phenolic and total flavonoid content of lyophilizate of the leaf of sweet potato leaf
Authors: Aliyah  , Aswad Muhammad , Hajrah  , Permana Andi Dian
Published: July 2021

Sweet potato (Ipomoea batatas L.) is one of the plants commonly used as traditional medicine, such as anti-inflammatory, anti-diabetes, anti-mutagenic and to increase platelet count. The benefits of sweet potato leaves have been reported as a result of the presence of antioxidant compounds and bioactive compounds, mainly phenolic and flavonoid compounds. In this study, we validated the spectrophotometry method of total phenolic and flavonoid compound of lyophilizate of the leaves of sweet potato juices. The results showed that the coefficient correlation (r) values were 0.97389 for gallic acid standard and 0.99869 for quercetin standard; the recovery rates ranged from 105.08% to 109.92% for phenolic, and from 87.48% to 94.36% for flavonoids respectively; precision with relative standard deviation values ranged from 0.7% to 0.4% for phenolic, and from 0.9% to 0.5% for flavonoids respectively; and the detection limit (LOD) and the quantitation limit (LOQ) for phenolic were 0.0425 μg/mL and 0.128 μg/mL respectively while for flavonoids were 0.17 μg/mL and 0.5 μg/mL respectively. The method was successfully applied in the determination of phenolic and flavonoid contents of lyophilizate of sweet potato leaf juices with the average total phenolic content of 9.83mg GAE/g lyophilizate, while the average total flavonoid level was 5.11mg QE/g lyophilizate.
Analysis of land productivity based on soil fertility in cocoa plantation land in Campalagian district, Polewali Mandar Regency
Authors: Rafiqah A N , Rasyid B , Neswati R
Published: July 2021

Potential areas for developing certain commodities can be determined by using the index value of land productivity. This study aims to analyze the land productivity of Campalagian District based on soil fertility level for the development of cocoa plants. The quantitative research method uses the Storie equation in determining the value of the land productivity index. Determination of observation points based on purposive sampling method. Soil properties determined in the field and the laboratory, including slope, effective depth, texture, pH, C-Organic, N-Total, P2O5, CEC, and the number of interchangeable bases. The results of the analysis of the land productivity index of the Campalagian district are classified as bad to good, with land productivity index values ranging from 13.89 to 51.37, with limiting factors, namely slope, effective depth, texture, C-Organic, and N-Total.
Implication of types of feeds combined goat manure for preference black soldier fly (BSF) : Hermetia illucens L
Authors: Indri I , Sjam S , Gassa A , Dewi V S
Published: July 2021

Hermetia illucens L. (Diptera: Stratiomydae) called black soldier fly (BSF) has an important role in the degradation of organic waste or bioconversion activity. The current study compared some types of feeds to preference BSF to eggs laid and the implication of the number of larvae and the size of pupae produced, the percentage of larvae that became adults. Type of feeds is rice bran, mixture of fruits waste, agricultural waste, vegetable waste and household waste. The type of feeds mixed with goat mature. The study reports that Black Soldier Fly (BSF) produced the hightest number of egg colonies in household waste (6 colonies) then vegetable waste (5 colonies), bran (4.3 colonies), fruits waste (3.3 colonies) and the lowest on agricultural waste (1 coloni). The highest number of larvae was in bran (4783), then household waste (1942), vegetable waste (1511), fruits waste (983) and the lowest in agricultural waste (276). The longest pupa size is in fruits waste (2 cm), household waste (1.96 cm), vegetable waste 1,84 cm), bran (1.51 cm), and the lowest is in agricultural waste (1.46). the highest number of imago was in the bran (2266 heads), vegetable waste (396 heads), fruits waste (95 heads), agricultural waste (674.3 heads) and the lowest was in household waste (661.3 heads)
The effectivity trap based plastic waste in monitoring of insects pests
Authors: Aminah Sri Nur , Mansur  , Salim  , Suyono
Published: July 2021

The plastic waste around us such as: plastic bottle and glass from drinking water very useful modified as tools for monitoring insect pests in agricultural ecosystem. The presence of insect pest in farmer plantation need more attention such as monitoring for exactly management effort. The purpose of research is to re-use plastic waste became yellow trap and pitfall trap for monitoring of insect pests attack the popular vegetables. The advantages of research as new information for community used plastic waste as tools of monitoring insects. The observation was held in kangkong and spinach plantation used pit-fall trap and yellow trap for monitoring presence arthropods in the planting season. The results was showed: the effectivity of pit-fall trap from plastic waste used for arthropods monitoring especially predator in kangkong field about 45% and insect pests 37.5%. As the comparing data, the effectivity of pit-fall trapped predator in spinach plantation about 99.2%, the lowest number in insect pests and decomposer about 0.4%, respectively. The result of yellow trap made from plastic bottle in kangkong field trapped insect pests about 43.7% and decomposer 41.1%. The trapped of insect pests used yellow trap in spinach plantation 63.4% and predator 26.6%. The conclusion of research: plastic giving more benefit as yellow and pit-fall trap for monitoring insects. The effectivities of tools depend on arthropods habit and roles as important part of ecosystem. Plastic waste has potential as monitoring tools presence insects in agroecosystem.
Dynamics of tungro disease and its vector population on intercropping of rice varieties
Authors: Apriyani R , Rosmana A , Patandjengi B
Published: July 2021

Tungro is one of the major diseases has ability reduce the yield potential of rice. The disease was caused by rice tungro baciliform virus (RTBV) and rice tungro spherical virus (RTSV). Both of virus only transmitted by green leafhoppers, Nephotettix virescens in a semi-persistent manner. The research purpose is to control tungro disease and its vectors as well as the diversity of natural enemies by applying the intercropping method of several rice plant varieties. The optimum of disease incidence in 11 weeks observation on the variety of Ciherang, Inpari 32, Inpari 36, and IR 64 planted in intercropping was 7.8%, 7.3%, 3,8%, and 6.3%. Whereas, the incidence on these respective variety planted in monoculture was 9.8%, 8,8%, 4.3%, and 8.5%. Then, the optimum of N. virescens population per clump on rice variety with intercropping in the same time of observation was 4.8, 2.3, 1.5, and 4, and on variety with monoculture was 6.5, 4.5, 3.3, and 4,5, respectively. Moreover, the population of insect predators tended to be higher on variety with intercropping than on rice variety with monoculture. These data indicated that rice planted with variety intercropping was related to the reduction of tungro incidence and its vector and also the increase of insect predators. Therefore, the intercropping of variety could used as one of control method against rice pests and diseases.
Farmer’s decision determining factors in harvest technology selection in rice farming
Authors: Zahara  , Slameto  , Novitasari Erliana , Asropi
Published: July 2021

Development of modern agricultural sector requires agricultural tools and machinery. Agricultural equipment and machinery technology is considered capable of increasing agricultural production and efficiency of time and labor. Furthermore, farmers’ decision on agricultural mechanization usage is influenced by internal and external factors. The recent study aims to determine the influencing factors toward farmer’s decision in harvest technology selection in rice farming. The research was conducted in Seputih Raman District, Central Lampung Regency in September – October 2016. The farmer’s decision determining factors were analyzed using binary logistic regression. As a result, the determining factors were the ease of operating rice harvester machines and land ownership status by farmers. However, new technology requirements are easy to adopt, one of which is the ease of testing. Therefore, technically harvester machine assembling is not complicated and easy to operate.
Algorithm of estimation suspended sediments concentration in Bili-Bili Reservoir
Authors: Faridah Sitti Nur , Achmad Mahmud , Samsuar  , Tantu Fatimah R.
Published: July 2021

The Bili-Bili Reservoir is located in the middle of the Jeneberang watershed in South Sulawesi Province, which was built for flood control, irrigation, raw water supply, and hydroelectric power plants. However, in the latest development, there has been a decline in utilization of the reservoir service function due to changes in the catchment area condition because of sediment. Estimation of sediment concentration in the Bili-bili reservoir was analyzed using spectrometer data. Estimation of Total Suspended Sediment (TSS) using a spectrometer by reflectance testing of the ratio between bands with various regression equations. Algorithm estimation of TSS concentration based on spectrometer measurements provides a coefficient of determination (R2) of 0.800 and an RMS error of 0.088, with a 3rd order polynomial equation for the green/red bands ratio: y = 62.667x3 – 154.328x2 + 121.27x – 29.902.
Strategy for the development of large scale rice milling industry in Maros Regency
Authors: Desi Salmah , Latief R. A.H , Hatta Jamil
Published: July 2021

Maros Regency had rice production of 295,800 tons in 2019, supported by 642 units of rice milling facilities, including 12 large-scale mills that spread across several districts. However, the existence of the facilities was not able to maximize the processing of rice production. The objectives of this study were (1) to analyze the current state (existing) rice milling facilities in Maros, (2) identify and analyze the factors inhibiting and supporting the development of rice milling facilities in Maros, (3) formulate development strategies of rice milling in the Maros Regency. The data analysis included Internal and External Strategic Factor Analysis by identifying the factors that have been made, IFAS Matrix Analysis (Internal Strategic Factor Summary Analysis), and EFAS Matrix (External Strategic Factor Analysis Summary) by determining the weight and rating on the IFAS matrix and EFAS and Swot analysis are carried out using a SWOT matrix analysis, by conducting a merger interaction (merger) of the internal factor group (Strength, Weakness), with the external factor group (Opportunity, Threat). The study results indicate that Strength - Opportunity (SO) produces the highest weight, namely 6.18, so the large-scale rice milling facilities in Maros Regency should take advantage of all strengths to seize and take advantage of the most significant opportunities.