bluuebunny/crossref_metadata_2025 huggingface dataset:
Exact quantisation of U(1)3 quantum gravity via exponentiation of the hypersurface deformation algebroid
Authors: Thiemann T
Published: October 2023

The U(1)3 model for 3+1 Euclidian signature general relativity (GR) is an interacting, generally covariant field theory with two physical polarisations that shares many features of Lorentzian GR. In particular, it displays a non-trivial realisation of the hypersurface deformation algebroid with non-trivial, i.e. phase space dependent structure functions rather than structure constants. In this paper we show that the model admits an exact quantisation. The quantisation rests on the observation that for this model and in the chosen representation of the canonical commutation relations the density unity hypersurface algebra can be exponentiated on non-degenerate states. These are states that represent a non-degenerate quantum metric and from a classical perspective are the relevant states on which the hypersurface algebra is representable. The representation of the algebra is exact, with no ambiguities involved and anomaly free. The quantum constraints can be exactly solved using groupoid averaging and the solutions admit a Hilbert space structure that agrees with the quantisation of a recently found reduced phase space formulation. Using the also recently found covariant action for that model, we start a path integral or spin foam formulation which, due to the Abelian character of the gauge group, is much simpler than for Lorentzian signature GR and provides an ideal testing ground for general spin foam models. The solution of U(1)3 quantum gravity communicated in this paper motivates an entirely new approach to the implementation of the Hamiltonian constraint in quantum gravity.
Early faint fault diagnosis of wheelset axlebox bearings in urban rail trains based on ICiSSA-MOMEDA
Authors: Yang Jianwei , Sun Runtao , Yao Dechen , Wang Jinhai , Li Xi , Hu Zhongshuo , Gao Cheng
Published: October 2023

Circulant Singular Spectrum Analysis (CiSSA) performs well in the decomposition and extraction of the periodic components of nonstationary signals. However, the decomposition of signals in complex environments suffers from spectral aliasing and difficulties in extracting feature information. Therefore, based on CiSSA, an improved CiSSA and multipoint optimal minimum entropy deconvolution adjustment (ICiSSA-MOMEDA) is proposed and applied to the early faint fault diagnosis of axlebox bearings of urban rail train wheelsets. First, the optimal embedding dimension was computed adaptively and accurately using an improved Cao’s method. Then, the initial components obtained from the decomposition were reorganized using the K-ARs method. ICiSSA effectively solves the problems of spectrum confusion and fault-information dispersion. Finally, ICiSSA was combined with MOMEDA to improve its ability to detect weak fault information. The superiority of ICiSSA-MOMEDA was verified based on the analysis of the actual bearing data and comparison with other methods.
Molecular dynamics simulation of the heterostructure of the CoCrFeMnNi high entropy alloy under an impact load
Authors: Chen Xiang , Liu Lei , Gao Rongjian , Lu Sheng , Fu Tao
Published: October 2023

There have been numerous experimental studies conducted on the CoCrFeMnNi high entropy alloys (HEAs) at the macroscopic level. However, it is challenging to quantitatively analyze the shock behavior of the HEAs from a microscopic level through experiments. In this study, we construct single-crystal, twin-crystal, multilayer, hole, and two-phase structures of the CoCrFeMnNi HEAs using the molecular dynamics method. The effects of impact loading on the microscopic level are investigated for CoCrFeMnNi HEAs with different structures. By analyzing the evolution of their microstructure and the changes in physical parameters, the response laws and propagation characteristics of shock waves in various heterogeneous of CoCrFeMnNi HEAs are revealed at the atomic scale.
Boosting learning achievement in physics among Ugandan form-2 students: effect of problem-based learning
Authors: Gumisirizah Nicholus , Muwonge Charles M , Nzabahimana Joseph
Published: October 2023

Enabling students to learn smoothly at an early stage of learning is a paramount effort that African education should takeoff. This study established the effect of problem-based learning (PBL) on students’ learning achievement. The participants were selected from form-2 of lower secondary schools in Sheema District, Western Uganda. Participants were randomly assigned to the treatment class with PBL instruction and the control class with content-based learning (CBL). A quantitative approach and a quasi-experimental design were used. Thus, the pretest-posttest non-equivalent quasi-experimental design was applied. A learning achievement test in simple machines was used as a data collection tool. The test was validated by experts and piloted with a split-half reliability (r = 0.87). Data was analysed in MS Excel and SPSS. A repeated measures analysis of variance revealed a very high statistically significant difference (p < .001) after learning in both classes. The same significance was found between PBL and CBL in favour of PBL. Classical test theory was used to present item difficulty and discrimination index. Teachers were recommended to adopt these methods with more practical hands-on activities to boost their skills and conceptual understanding.
Einsteinian gravitational concepts throughout secondary school
Authors: McInerney Corey , Sutton Phil
Published: October 2023

Einstein’s theory of relativity is largely thought of as one of the most important discoveries of the 20th century and continues to pass observational tests over 100 years later. Yet, it is Newtonian gravity, a 350 year old formalism proven to be less accurate than relativity, which is taught in schools. It has been shown that Einsteinian gravitational concepts can be well understood by students in both primary and secondary education. In this paper, a cross-section of students from Yr 7 to 13 enrolled in an English secondary school took part in an intervention designed to introduce the idea of gravity from spacetime curvature. The overall aim of this work is to assess the viability of including relativity in the secondary curriculum and to ascertain which year this material would be best placed in. We determine that all year groups where able to appreciate the effects of curvature to some extent. Visual demonstrations aided conceptual understanding at Yr 7–8 level, but this does not have a strong effect on their ideas around the source of the gravitational force. Participants in Yr 9–13 were able to understand concepts beyond those introduced in the demonstrations. However, a deeper understanding of curvature as the source of the gravitational force is not seen until years 12 and 13. We find that those in Yr 13 have the best overall understanding of the concepts introduced during our intervention.
Streamer-to-filament transition in pulsed nanosecond atmospheric pressure discharge: 2D numerical modeling
Authors: Zhang Bin , Zhu Yifei , Zhang Xiaobing , Popov Nikolay , Orriere Thomas , Pai David Z , Starikovskaia Svetlana M
Published: October 2023

The streamer-to-filament transition in air at atmospheric pressure, in a nanosecond pin-to-pin discharge, is studied by a 2D model. The main aim is to implement a kinetic scheme providing a sharp electron density increase to the 2D PASSKEy code, to validate the results on the available experimental data, and to investigate the mechanisms responsible for the transition. Results show that after the formation of a conductive channel across the discharge gap, two discharge modes appear during a few nanoseconds: a glow phase, with a relatively homogeneous distribution with the electron density of

1.0
×

10

14

cm−3, and a filamentary phase, with the electron density of

1.0
×

10

18

cm−3. Two filaments appear at the cathode and anode respectively, and propagate towards the middle of the gap with a velocity of about

1.1
⋅

10
7

cm s−1, forming a narrow channel. Simultaneously, the gas temperature increases from 350 to 2800 K. The diameter of the channel at the middle gap decreases from 210 to 90 µm. Dissociation and ionization of the electronically excited states of molecules N2(A

3

∑

u

+

, B

3

Π
g

, a

′
1

∑

u

−

, C

3

Π
u

), and ionization of ground and electronically excited states of O and N atoms are the most important processes for the transition. Numerical results also reveal the influence of the memory effect (pre-heating, pre-ionization, and pre-dissociation) from previous pulses on the streamer-to-filament transition.
Universal correlations along the BEC-BCS crossover
Authors: Obeso-Jureidini J C , Domínguez-Castro G A , Neri E , Paredes R , Romero-Rochín V
Published: October 2023

Universality of the long-distance behavior across the Bardeen–Cooper–Schrieffer (BEC)-Bose–Einstein condensate (BCS) smooth transition for two-body density correlation functions and the Cooper-pair probability density is demonstrated in a balanced mixture of a two-component Fermi gas at T = 0. It is numerically shown at the mean-field level that these two-body quantities exhibit an exponential decay in terms of the chemical potential and the low-energy behavior of the gap. A general expression is found for the two-body distributions holding for different features of finite-range potentials, such as divergences at the origin, discontinuities at a finite radius, power-law decay, and exponential decay. The correlation length characterizing the long-distance behavior unravels the dependence on the energy needed to break pairs along the BEC-BCS crossover, a quantity meaningful to the stability of the many-body state.
Anomalous luminescence temperature dependence of (In,Ga)(As,Sb)/GaAs/GaP quantum dots overgrown by a thin GaSb capping layer for nanomemory applications
Authors: Sala Elisa Maddalena , Klenovský Petr
Published: October 2023

We study (In,Ga)(As,Sb)/GaAs quantum dots (QDs) embedded in a GaP (100) matrix, which are overgrown by a thin GaSb capping layer with variable thickness. QD samples are studied by temperature-dependent photoluminescence, and we observe that the QD emission shows anomalous temperature dependence, i.e. increase of energy with temperature increase from 10 K to ∼70 K, followed by energy decrease for larger temperatures. With the help of fitting of luminescence spectra by Gaussian bands with energies extracted from eight band

k

⋅

p

theory with multiparticle corrections calculated using the configuration interaction method, we explain the anomalous temperature dependence as mixing of momentum direct and indirect exciton states. We also find that the k-indirect electron–hole transition in type-I regime at temperatures

<

70

 K is optically more intense than k-direct. Furthermore, we identify a band alignment change from type-I to type-II for QDs overgrown by more than one monolayer of GaSb. Finally, we predict the retention time of (In,Ga)(As,Sb)/GaAs/AlP/GaP QDs capped with GaSb layers with varying thickness, for usage as storage units in the QD-Flash nanomemory concept and observe that by using only a 2 ML-thick GaSb capping layer, the projected storage time surpasses the non-volatility limit of ten years.
A quantum Otto engine with shortcuts to thermalization and adiabaticity
Authors: Pedram A , Kadıoğlu S C , Kabakçıoğlu A , Müstecaplıoğlu Ö E
Published: October 2023

We investigate the energetic advantage of accelerating a quantum harmonic oscillator Otto engine by use of shortcuts to adiabaticity (for the expansion and compression strokes) and to equilibrium (for the hot isochore), by means of counter-diabatic (CD) driving. By comparing various protocols with and without CD driving, we find that, applying both type of shortcuts leads to enhanced power and efficiency even after the driving costs are taken into account. The hybrid protocol not only retains its advantage in the limit cycle, but also recovers engine functionality (i.e. a positive power output) in parameter regimes where an uncontrolled, finite-time Otto cycle fails. We show that controlling three strokes of the cycle leads to an overall improvement of the performance metrics compared with controlling only the two adiabatic strokes. Moreover, we numerically calculate the limit cycle behavior of the engine and show that the engines with accelerated isochoric and adiabatic strokes display a superior power output in this mode of operation.
Remedial Measures to Protect Transmission Tower from Excessive Soil Movement : A Case Study
Authors: Sulancana B , Kurniawati W , Wibowo P A , Taufika Y S
Published: October 2023

The research background focused on investigating deformation in the T.73 Nonohonis-Kefamenanu transmission tower structure that was suspected to be caused by soil movement due to the tower’s location on a sloped area. To analyze this, various tests were conducted to examine the soil properties and slope stability considered the impact of intense rainfall. The Cone Penetration Test (CPT) results revealed hard soil at depths of 6.8 meters (S1), 8.4 meters (S2), and 7.4 meters (S3), falling within the Silty Sand to Sandy Silt - Sand zone, with qc > 200 kg/cm2. Boring & N-SPT tests indicated hard soil with N-SPT values > 50 at depths of 18 meters (BH-1) and 8 meters (BH-2). The geoelectrical survey using the Wenner-Schlumberger configuration found a groundwater layer at 3-5 meters and suggested the presence of a slip plane. Janbu’s method was used to analyze slope stability, taking into account the complex profiles, layers, and soil characteristics. Modeling results showed minimum safety factors after rainfall (SF 1 = 1.827) and after 30 days (SF 3 = 3.302) following the installation of a 15-meter bored pile foundation with a 50-ton load at the chimney.
Investigating the Stability of the Candi Kelir using DDA
Authors: Octavia Karina , Wu Jian-Hong , Handoko Luky
Published: October 2023

Candi Kelir, which is a candi in Prambanan, is a historical masonry structures threatened by high potency of earthquake in Indonesia. Investigating the stability of Candi Prambanan is essential for determining the capability to withstand earthquake loads. Discontinuous Deformation Analysis (DDA) has been extensively applied in the disciplines of rock mechanics and rock engineering. Two-dimensional DDA is chosen to simulate the behaviour of Candi Kelir towards earthquake load. Geometry of each block of Candi Kelir is obtained by Close Range Photogrammetry (CRP) method. Simulation of Candi Kelir is conducted using the seismic excitation from the destructive 2006 Yogyakarta Earthquake. The result of the simulation shows the capability of DDA to simulate the behaviour of masonry structure which allows fully detachment of the blocks. During the earthquake, most of the top structures are failing, thus DDA can simulate and generate the result. Wider application of DDA into the historical masonry structure will be helpful to prevent more damage due to earthquakes.
Development of Plane Strain Ratio for Soil Nailing Wall in Clay
Authors: Lyman R A , Lim A
Published: October 2023

Deep excavation analysis, the numerical modelling is now often utilized. Deep excavation is, in fact, a three-dimensional issue. Two-dimensional analysis is still often used for practical purposes. For deformation analysis, plane strain ratio (PSR) is an option to acquire three-dimensional behaviour from two-dimensional analysis. For braced excavations, PSR is well established, but it is yet unknown how to construct retaining walls using soil nails. The aim of this paper is to propose the PSR chart for a soil nailing wall used as a retaining structure in clayey soil with an asymmetrical layout. The excavation case history is adopted for this study. Later, the length (L) and width (B) of the excavated area were varied as part of three-dimensional parametric research to create a soil nailing wall PSR chart.
P-y Curve for Estimation Lateral Bearing Capacity of Single Bored Pile in Overconsolidated Soils Using The Three-Dimensional Finite Element Method.
Authors: Tommy A , Widjaja B , Hutabarat G M
Published: October 2023

The p-y curve method is widely used to predict piles’ lateral bearing capacity. It assumes independent springs with a non-linear modulus of subgrade reaction for analyzing soil resistance (p) and deflection (y). This study determined the lateral bearing capacity using the three-dimensional finite element method (FEM-3D) and finite difference method (FDM), which was later compared with the loading test results. Therefore, the pile head condition is assumed to be the free-head. To determine the lateral bearing capacity, input the lateral deflection at the pile head. In FEM-3D, the pile and lateral deflection in the pile head is modeled using cluster elements and surface-prescribed horizontal displacements, respectively. On the other hand, in FDM, pile heads and boundary conditions are modeled using displacement and moment. The results of the lateral bearing capacity using FEM-3D provide predictions that are close to the loading test, with a difference of about 4.2%. In contrast, the FDM method produced conservative results due to its reliance on semi-empirical formulas. The ultimate soil resistance (Pult) formula in FDM is more suitable for rigid-pile behavior. The prediction of lateral bearing capacity using FEM-3D provides more accurate results due to its ability to model complex soil-pile interaction. The stress history, soil-pile interaction, and more reliable constitutive models can be modeled in FEM-3D.
Innovations in Micropile Testing Using Distributed Optical Fibre Sensors
Authors: Mohamad H , Tee B P , Beddelee A A A M , Khoo C M , Ghazali M F , Nasir M Y M
Published: October 2023

Micropiles are primarily used in situations where traditional foundation methods, such as large-diameter bored piles or driven piles, are not feasible due to various constraints, including limited access, low headroom, or the need to work in environmentally sensitive areas. They are often employed in urban areas with restricted space or for underpinning existing structures. Two case studies of instrumented micropiles are presented in this paper, with the aim to showcase innovations in pile testing using Distributed Optical Fibre Sensing (DOFS). In the first project, micropiles were installed as part of an underpinning work where several existing piles were removed to allow safe passage of Tunnel Boring Machine (TBM) underneath the building. An experiment pile was instrumented with conventional and DOFS sensors to measure pile responses due to tunnelling in proximity. In the second project, the micropile was tested to determine its load carrying capacity for buildings constructed in hilly area. In both cases, API pipes were applied and socketed into bedrocks. Optical cables were attached on four sides of the steel pipes and subsequently grouted. During the load tests, DOFS data were able to display precisely the shaft distribution of micropiles when subjected to vertical loads as well as bending behaviour due to the close proximity tunnelling. Interpretations of distributed strain profiles from DOFS have contributed to a better understanding of API-reinforced micropile performance under complex geological and loading conditions.
Stabilization of Batu Pahat Peat by Using Rice Husk Ash (RHA)
Authors: Abu Talib M.K , Zainorabidin A , Pakir F , Md Yusof Z , Basri K. , Salikin A.
Published: October 2023

Malaysia possesses the distinction of being the ninth biggest expanse of peat soil land globally, hence encountering significant geotechnical challenges characterised by elevated moisture content, substantial organic composition, diminished shear strength, and reduced bearing capacity. The objective of this study is to investigate the fundamental geotechnical characteristics and strength of Batu Pahat peat that has been stabilised using Ordinary Portland Cement (OPC) and Rice Husk Ash (RHA). The application of Ordinary Portland Cement (OPC) in the process of peat stabilisation has the potential to enhance the mechanical properties and strength of the soil. Nevertheless, the extensive utilisation of cement might result in environmental degradation. Therefore, it is imperative to consider the incorporation of agricultural waste by-products as a partial substitute for cement. Hence, the objective of this research is to employ Rice Husk Ash (RHA) as a supplementary material in cementitious systems. An experimental investigation was undertaken to determine the ideal mix ratio by replacing cement with rice husk ash (RHA) in the range of 5% to 20%. The findings indicate that the peat under investigation can be classified as a hemic peat variety characterised by a high level of acidity. The experimental findings indicated that the peat treated with a 5% concentration of rice husk ash (RHA) (referred to as C95 RHA5) exhibited the maximum Unconfined Compressive Strength (UCS) value of 262 kN/m2. To validate the findings of the Unconfined Compressive Strength (UCS) test, an additional analysis was performed using the Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX) technique. This examination aimed to confirm the presence of calcium, which serves as evidence for the observed improvement in strength. In conclusion, it can be inferred that the utilisation of RHA as a substitute for cement at a proportion of 5% exhibits potential for application in Hemic peat.
Microstructure Behaviour of the Marine Clay Treated with Geopolymer
Authors: Pakir F , Abdullah M , Zainorabidin A , Talib M K A , Yusof M Z M , Salikin A , Yunos N Z M , Othman B A
Published: October 2023

Marine clay usually related with poor soil properties, high settlement and instability that are not suitable for engineering requirements and low compressive strength. To solve this problem, chemical stabilizer is one of the soil stabilization method in construction industry which one of them are geopolymer stabilizer to increase the strength of marine clay soil. However, the study regarding of microstructure treated marine clay using geopolymer are less study. Hence, this study focus on the microstructure behaviour of treated marine clay using geopolymer stabilizer. The approach employed in this investigation was the preparation of the sample by the incorporation of marine clay soil and geopolymer (addition of 6% Magnesium Chloride (MgCl2)). The sample was then subjected to several microstructure tests, including X-Ray Diffraction (XRD), Particle Size Analysis, and Scanning Electron Microscopic (SEM). The findings demonstrate the alterations in the microstructural characteristics of marine clay following the application of geopolymer stabilization. According to the results of the XRD analysis, no further peaks were observed. Conversely, the SEM examination revealed a reduction in the voids within the marine clay soil, leading to increased density as the curing period increased. Furthermore, the Particle Size Analysis reveals that the use of a stabilizer results in a notable augmentation in the soil particle sizes. Consequently, This study may be utilized to examine the relationship between the microstructure and mechanical properties of treated soil.
Potential of Methanotroph bacteria as non-symbiotic nitrogen fixation in rice paddy fields in Morowali regency
Authors: Marhani  , Sahur A , Adrianton  , Jeki
Published: October 2023

Nitrogen makes up about 78% of all the gases in the atmosphere. Although it is very abundant in the atmosphere, nitrogen cannot be used directly by plants. The aims of this study were to isolate, characterize and identify the morphology and physiology of methanotrophic bacteria, calculate the total population of methanotrophic bacteria and analyze the chemical properties of paddy rice soil in Morowali Regency. Results Based on the gram reaction test, 11 isolates were gram negative, 11 isolates were catalase positive, 11 isolates were capable of nitrogen fixation, five isolates were yellowish white, five isolates were white, one isolate was yellow, six isolates had a convex elevation, and five isolates had a flat elevation. Based on the identification results, the Witaponda sub-district produced five isolates, three isolates from Bumiraya, two isolates from Bungku Barat and one isolate from Bungku Tengah District. Based on the results of the calculation of the number of bacteria found in Witaponda subdistrict as much as 54.05x106 Cfu/mL Bumiraya as much as 40.21x106 Cfu/mL, Bungku Barat as much as 12.06x106 Cfu/mL, Bungku Tengah as much as 11.65x106 Cfu/mL. The results of the analysis of soil chemical properties showed that pH, CEC, organic C, P205, K were classified as low in both irrigated and rainfed rice fields.
The metabolomic profile of Garcinia intermedia leaves with several sample drying methods
Authors: Budiyanti T , Nawfetrias W , Mansyah E , Indriyani NLP , Reninta R , Husada ED
Published: October 2023

Garcinia intermedia, commonly called cherry mangosteen or lemon drop mangosteen, originates from Mexico and Central America. This plant is not cultivated in Indonesia because the fruit is less tasty than mangosteen (Garcinia mangostana). Information about the metabolome content in Garcinia intermedia needs to be known to increase its commercial use. Several studies have shown that this species has anti-microbial content that benefits health. This study aims to perform metabolomics profiling in the leaves of Garcinia intermedia using 3 (three) treatments of leaves drying methods such as air-dried (room temperature), freeze-drying, and oven (hot air) through Gas Chromatography-Mass Spectrophotometry (GC-MS). The results identified a total of 35 different compounds in the leaves of Garcinia intermedia. The highest area pct was Friedelan-3-one (29.92%) obtained from air-dried preparation method. The other identified compounds were the sesquiterpenes group (beta-Caryophyllene, gamma-Muurolene, Naphthalene,1,2,3,5,6,8a-hexahydro-4,7-dimethyl-1- (1-methylethyl)-,(1S-cis)-, and 1-Isopropyl-4,7-dimethyl-1,2,3,5,6,8a-hexahydronaphthalene), Alkane group (Octadecane and Heptacosane) and vitamin E (delta-Tocopherol and dl-alpha-Tocopherol). This study revealed the insight of potential uses of Garcinia intermedia leaves extract with additional functional metabolites that could further be used to discover potential drugs that benefits for human health.
Forest conversion to agricultural lands: impact on soil physical characteristics
Authors: Hasanah U , Amami A A , Amelia R
Published: October 2023

Forest conversion to other land uses, particularly for agriculture, has been prevalent worldwide, with Indonesia being particularly affected. The removal of forest cover, which exposes the organic matter to more severe climatic conditions, leads to a deterioration in the physical characteristics of the soil. This paper investigates the alterations in various soil physical properties when forests are converted into agricultural land uses, including fallow areas with shrubs, wetland rice cultivation, cacao plantations, durian plantations, and avocado plantations. Both undisturbed and disturbed soil samples from each land use were analyzed to assess hydraulic conductivity, bulk density, and soil organic carbon (C) content. With the exception of wetland rice, all land uses exhibited a sandy loam texture. The forests contained the highest amount of SOC (4.70%), while the other samples contained less than half (2.01%) of this quantity.
Review: Population establishment and genetic study of Java, Bali and Sumatra Salak crossing
Authors: Hadiati Sri , Indriyani Ni Luh Putu , Jumjunidang
Published: October 2023

Indonesia has a high diversity of Salak. The cultivars that are widely cultivated are Salak Pondoh, Java, Bali, and Sumatra. These cultivars have a delicious taste and different superiorities. The crossing was needed to combine their superiorities and obtain superior varieties. Crosses result in 17 hybrids Salak populations with moderate to high diversities. Salak Sidimpuan (SDP, SDS, SDM) and the progenies derived from crossing Salak Sidimpuan as female parents have a larger plant and leaflets size but have relatively few leaves. Salak Bali, Salak Sidimpuan, and the progenies derive from crossing Salak Sidimpuan as the female parents have a flesh thickness of 1.0 cm. A crossing between Salak Pondoh (non-astringent) x Salak Java (astringent) and a crossing between Salak Sidimpuan (astringent) x Salak Sanjung (astringent) produced progenies whose fruit have an astringent taste. On the other hand, the crossing between Salak Sidimpuan x Mawar produce partially astringent fruit and some non-astringent. Selection of these progenies resulted in three superior varieties, namely Sari Intan 48, Sari Intan 541, and Sari Intan 295, and an ideal candidate variety, namely PH-MW (35-13), with the advantage of thick flesh, sweet and non-astringent taste, fruit weight > 65 g, and fragrance.
Effectiveness of media B5 (Gamborg) for multiplication of Sengon (Paraserianthes falcataria L. Nielsen) in vitro
Authors: Gusmiaty  , Syamsinar  , Restu M , Iswanto  , Aida N , Larekeng S H
Published: October 2023

Paraserianthes falcataria (L.) Nielsen, also known as sengon, is one of the most important and adaptable pioneer species. The Sengon plant is one of the quickest-growing tropical plants. The objective of this study was to identify the optimal medium for sengon multiplication with the addition of ZPT, cytokinin, BAP, and kinetin, either singly or in combination. The research design employed was an entirely random design (CRD). Media M2 (B5 + BAP 0.1), which was the medium with the highest number of shoots, was determined to be the optimal medium for sengon plantlets in the study. At 1 MST, the fastest medium for leaf emergence was (B5 + BAP 0.2) media. The poisson test analysis shows that, in comparison to other media, the M2 medium (B5 + BAP 0.1) has a very significant impact on the quantity of leaves. The medium with the highest average height of sengon plantlets was M1 (B5 Control), with 1.73 cm. The highest percentage of dead plantlets on M4 medium was 33%, while on M9 medium it was 17%, due to browning leading to cell death. Only media M4 (BAP 0.2), M5 (Kinetin 0.2), and M9 (BAP (0.2) + Kin (0.2) contained plantlets contaminated by bacteria at a concentration of up to 17%, which inhibited plantlet growth.
Physical and chemical characteristics of 12 local varieties of Banggai Yam (Dioscorea spp.)
Authors: Kadekoh I , Basri Z , Tellu A T , Sundu B , Rahim A , Lamusa A , Rois  , Yusuf R
Published: October 2023

Banggai yam is a yam originating from the Banggai Islands and Banggai Laut Districts, Indonesia, and has been the leading food for the population for generations and can be an alternative food to replace rice. This research was conducted to determine the physical characteristics (shape and color of tubers) and chemicals (water, ash, fiber, fat, protein, and carbohydrates) of 12 varieties. Yams are obtained from farmers’ harvests taken at random. Physical characteristics were observed visually, while chemical analysis was analyzed according to AOAC (1990). The shape of the tuber is round, oval, elongated, fingered, and branched. The colors of the bulbs are white, red, yellow, and purple. The lowest average moisture content was found in Solopia (5.32%) and the highest was found in Lendut (7.52%), the lowest ash was found in Sombok (1.76%), and the highest was obtained in Liboko (3.45%). The lowest fat was found in Butun (0.53%), and the highest was found in Doso (2.39%), the lowest fiber was found in Doso (0.80%), and the highest was found in Liboko (1.79%), the lowest protein was found in Doso (4.42%) and the highest was in Lendut (9.27%), the lowest starch was found in Liboko at 80.38%, and the highest was found in Danggang at 86.63%, the lowest amylose was 13.38% in Pusus, and the highest was found in 25.11% in Boan mbol, the lowest amylopectin was 74.89% in the Boan mbol variety, and the highest was 86.62% in the Pusus variety, and the most inadequate glucose was 0.54% in Pusus sago, and the highest was 2.44% in Solopia. Banggai yam has the potential as a source of healthy alternative food and can be developed as a functional food and food diversification.
Evaluation of nutrient status and soil fertility and utilization of local weeds as organic fertilizer in agricultural land affected by liquefaction natural disaster
Authors: Isrun Isrun
Published: October 2023

The study’s first phase results identified 17 species of weeds with 11 species of low index class and six species of medium index class. Based on nutrient content, there were four locations with low fertility status, SPL1, SPL5, SPL6 and SPL7. In addition, there were three locations, SPL2, SPL3, and SPL4, with moderate fertility levels. In the study’s second phase, the highest pH H2O (6.38) was obtained at a dose of 25 tons per ha of Bokashi weed and 225 kg per ha of SP-36. This treatment was significantly different from other treatments. The highest available phosphorus was detected at a dose of 25 tons per ha of Bokashi weed 225 kg per ha of SP-36, namely 28.87 ppm, which was significantly different from other treatments. Moreover, there was an increase phosphorus uptake in plant due to the application of Bokashi fertilizer and SP-36 fertilizer. P uptake increased at a dose of 25 tones of Bokashi fertilizer per ha (P3) and SP-36 fertilizer dose of 225 kg per ha (S3) with an average of 0.68 g per plant.
A single control area policy as a threat to food security in West Lombok Regency
Authors: Tajidan Tajidan , Halil Halil , Siddik Muhamad , Sofwan Sofwan , Yunidiya Dini Rizka
Published: October 2023

Land conversion from agriculture to non-agriculture is currently taking place, and it is suspected that it will become more massive if the single-area policy is enforced. The study aims to modify the formulation of the carrying capacity index of sustainable food-agriculture land in accordance with the single-control regional policy to maintain self-sufficiency in rice food. Primary data collection uses survey techniques, in-depth interviews, and focus group discussions. Secondary data was obtained by applying the desk study literacy method. The projected rice demand data of the population is multiplied by the average need for rice per person, while the food supply is calculated by average land productivity and annual cropping index. The land carrying capacity index can be modified from a production needs approach to a paddy field needs approach, and the land carrying capacity index can be used to analyze sustainable food needs. Food security in West Lombok District is able to return to self-sufficiency in food until 2030, but due to the policy of a single control area, food self-sufficiency is threatened with however, unless increasing the cropping index to 300% per annum.
Farmer card as an instrument for fertilizer direct subsidy on Lombok Island, Indonesia
Authors: Zaini A , Sa’diyah H
Published: October 2023

Like other direct subsidies using subsidy cards, direct fertilizer subsidies using farmer cards are believed to be a mechanism for providing subsidies that are more appropriate for target farmers. However, before this policy is widely implemented, it is necessary to carry out a trial phase for its implementation. The trial was carried out in Sekarbela District, Mataram City with the consideration of the availability of relatively complete data on subsidy recipient farmers accompanied by a National Identity Number (NIK). The trial results indicated that the farmers receiving the subsidy were generally young (48-50 years old), had more than 20 years of farming experience, and most of them controlled land of less than 0.5 hectares with ownership, lease or cultivation status. However, most of the farmers (88%) have only elementary school education but are active in preparing the Group Needs Definitive Plan (RDKK). The results of the analysis conclude that the probability of using a Farmer’s Card to obtain subsidized fertilizer is smaller for tenant farmers compared to owning or cultivating farmers. In addition, farmers with a higher level of education have a greater probability of using the farmer’s card as a means of obtaining subsidized fertilizer.
Socio-economic mapping for community empowerment in Mandalika special economic zone, Lombok, Indonesia
Authors: Sayuti R H , Taqiuddin M , Hayati  , Evendi A , Hidayati S A , Asri K H , Sopian E
Published: October 2023

The community’s welfare is anticipated to increase with development in highly prioritized regions of the country’s tourism industry. Studies, however, indicate that this is not always the case. If the process of social engineering is not taken seriously, even poverty will continue to cast a shadow over the neighborhood. What about the Mandalika Special Economic Zone (SEZ), which has been designated as a new area for economic growth and has had expensive tourism amenities constructed? This study aims to map the social and economic state of the neighborhood surrounding the Mandalika Special Economic Zone (SEZ). This study employed mixed methods, which combine quantitative and qualitative techniques. Maps representing the community’s social and economic situations are produced quantitatively. A qualitative approach uses a participative procedure to create a community empowerment model. The study’s findings are: (1) The community’s social and economic situations are underwhelming. Public health infrastructure, such as drinking water facilities, sanitization, and waste disposal, is still subpar. People in SEZ Mandalika still have modest incomes, and many are even considered impoverished. (2) The community’s human, ecological, and cultural resources contribute to its potential. Numerous forms of tourism infrastructure have been constructed. (3) There are five components to the suggested community empowerment model: the government, academia, community, media, and business actors (Penta helix).
Technical efficiency with stochastic production function frontier of seaweed farming in Pantai Amal, Tarakan City
Authors: Jumiati E , Mubarak A , Ismandari T , Amarullah  , Kusnadi E
Published: October 2023

Efficiency in production is very important to produce optimal production. An important factor in carrying out production efficiency is the use of inputs or production factors so as to produce optimal output. This is often called technical efficiency. The sampling technique was carried out using a non-probability sampling method, while the method or technique used is purposive sampling, with certain considerations, namely: seaweed farmers who have been farming for at least 1 year, the farmer’s age is at least 17 years. The number of samples was carried out by quota as many as 60 seaweed farmers. Methods of data analysis Technical efficiency is analyzed using the stochastic frontier production function, in this case the form of the production function is the Cobb Douglass production function. The results showed (1) the factors that affect the technical efficiency of seaweeds are land area, amount of seeds, labor force, age, education, and farming experience. (2) The average level of technical efficiency of seaweed farmers in Tarakan City in general is 0.974 (efficient). The factor that can reduced technical inefficiency was education. education has a negative relationship and was significant in increasing technical efficiency.
Analysis of corn commodity production and development policy in North Minahasa, North Sulawesi Province
Authors: Sondakh Joula O M , Paat Paulus C , Markus Rawung Jefny B , Lintang Meivie , Layuk Payung , Rembang Janne H W
Published: October 2023

North Minahasa Regency is a corn development area in North Sulawesi, but its production is still low. The aim of the research is to obtain data on corn production systems and their development policies. Survey and FGD data collection techniques. Implementation February - March 2020. Analysis of quantitative data using multiple linear regression. The results showed that farmers are starting to use new superior varieties that have higher potential than local varieties, but the use of cultivation technology is still in accordance with farmers’ habits. The results of the coefficient test, the results of the t test or the sig probability value show that the area of land and labor has a calculated t value of 2.532 and 2.221; bigger than t table (2.064). This means that the variable land area and labor have a significant effect on corn production at α 5%. The potential for the development of this commodity is quite promising, but it is necessary to increase production referring to cultivation technology and product diversification.
Determination of antimicrobial resistance profile of Salmonella enteritidis isolated from chicken and human in Indonesia
Authors: Ariyanti T , Sukatma  , Suhaemi  , Mulyati S , Rachmawati F , Noor SM
Published: October 2023

Salmonella enteritidis, a foodborne pathogen, can be transmitted to humans through direct contact with infected livestock or consumption of contaminated chicken food. The excessive use of antibiotic in both animals and humans can lead to the development of antimicrobial resistance in bacteria. The profile of antibiotic resistance was identified by this study. A total of 52 S. enteritidis isolates were tested for antibiotic susceptibility in the Research Center for Veterinary Science of the National Research and Innovation Agency (BRIN). These isolates were obtained from various source, including chickens (41 isolates), feed (2 isolates) farm water (2 isolates), and humans (7 isolates). The Antimicrobial Sensitivity Test (AST)was performed using the agar diffusion technique (Kirby-Bauer method). The results revealed that S. enteritidis exhibited resistance to 11 antibiotics. The highest resistance rates were observed for Colistine sulphate (75%), Meropenem (67.31%), and Nalidixic acid (67.31%). Other antibiotics to which resistance was observed included Cefotaxime (65.38%), Ampicillin (61.54%), Ceftazidime (50%), Streptomycin (26.92%), Gentamycin (15.38%), Tetracycline (9.62%), Chloramphenicol (5.77%), and Ciprofloxacin (1,92%). It was found that the S. enteritidis isolates were multi-drug resistant, with 73,08% of the isolates showing resistance to 1-5 antibiotics, and 26,92% displaying resistance to 6-10 antibiotics. These findings indicate that the local isolates of S. enteritidis obtained from chickens and humans in this study exhibited resistance to the tested antibiotics, potentially attributed to antibiotic therapy or the spread of resistant strains.
Kabonga Besar mangrove ecosystem health status, Donggala, Indonesia – an analysis of viability versus threats
Authors: Rizal A , Mallombasang S N , Widiastuti I M , Mansyur K , Nirwana  , Fachruddin  , Umar
Published: October 2023

Mangrove ecosystem functions mainly to provide habitat for thousands of marine species, prevent erosion and stabilize shore-line. Based on that, this research aims to determine the health status of the mangrove ecosystem located at Kabonga Besar, Donggala, Indonesia, by assessing its viability and threat level. This research was critically important as the mangrove ecosystem is being designated by the Government of Indonesia as a site for recreational use. The method used was qualitative research applying a series of focus group discussions involving interviews and observation. Data collection processes involved observing the ecosystem condition, interviewing key stakeholders, and studying relevant documents. The obtained data, i.e., Key Ecological Attribute covering the aspect of Landscape Context, Condition, and Size, and Threat data were analyzed using The Conservancy’s Framework for Viability and Threats. Viability and Threats were analyzed using the Software Application of CAP v6b. The results show that the viability of the mangrove ecosystem was good, but the threat level was high. To improve the ecosystem, as part of the coastal management, the health status of the site should be enhanced by increasing its viability or decreasing its threat level.
Pesticides affecting the diversity of pollinator insects in cocoa plantations (Theobroma cacao L.)
Authors: Hasriyanty  , Rosmini  , Pasaru F , Mutmainah  , Alimuddin S , Pratiwi M
Published: October 2023

Pollinating insects play a significant role in the pollination process of cocoa flowers because unpollinated cocoa flowers will fall within 24 hours and fail to develop into fruit and seeds; on the other hand, the presence of pollinators in cacao plants is influenced by cultivation techniques such as the use of pesticides to against pest and disease attacks. This study aims to determine the diversity of pollinating insects in cacao plantations with and without pesticides. The study included field research on cocoa plantations in Rahmat Village, Palolo Sub-district, Sigi Regency. Insect identification was carried out at the Plant Pests and Diseases Laboratory, Faculty of Agriculture, Tadulako University, Palu. Sampling was carried out in 3 plots measuring 40×40 m² with treatments: application of Chlormite 505 EC insecticide at a dose of 20ml/15L water, Lamda Cyhalothrin 247 ZC insecticide at an amount of 10ml/15L water, and control. In each plot, ten trees were selected for observation. Insect pollinators and flower visitors were collected using yellow pant traps and direct observation. The results of this study found six species of pollinator insects, namely Forcipomyia sp. and Bactrocera sp. from the order Diptera, Lasius niger, Solenopsis invica, and Vespidae from the order Hymenoptera, and Melantis sp. from the order Lepidoptera. Insecticide application affects pollinating insect diversity.
Strategic environmental assessment in Palu Central Sulawesi reflecting water provision profile based on ecosystem services
Authors: Sangadji MN , Rahmatu R , Nursalam  , Rahman A , Kurniawan M , Musbah M
Published: October 2023

Reconciling development activities with Natural resources conservation has become one of the essential elements in the search for sustainable development. The degradation of Natural resources attributed to human activities through development increase rapidly. This trend is exacerbated by policies encouraging land conversion and natural resource overexploitation, as well as a need for more information about the value of natural resource conservation. Consequently, it can alter the ecosystem and change the natural resources and their functions. Protecting natural resources begins with policymaking, followed by development plans and programs. In this study, describe how the Strategic Environmental Assessment (SEA) is a safeguarding tool for controlling natural resource loss in Palu City, Central Sulawesi. Natural resources are one of the vital aspects to be considered in SEA. Development in the central city, opening the land for agriculture on a large scale (plantation), and mining were the main issues that contributed to high risk to the natural resources. Regional development plans and programs assess by predicting, evaluating, and mitigating the environmental impact produced by the development. Our study found that the involvement of multi-stakeholders, Government, legislative, universities, social communities, and nongovernmental organizations successfully collected strategic development goal issues related to natural resources conditions in Palu, Central Sulawesi. Assessment of the plans and programs of development that will contribute to the mitigation of natural resource degradation and decide alternative recommendations for regional development plans and programs. This study demonstrates the integration of SEA in controlling natural resource degradation due to development.