bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppressed thermal conductivity in hyperstoichiometric uranium dioxide controlled by phonon lifetimes
Authors: Ma Hao , Bryan Matthew S. , Pang Judy W. L. , Abernathy Douglas L. , Antonio Daniel J. , Gofryk Krzysztof , Manley Michael E.
Published: July 2022

Thermal transport in nuclear fuels used for nuclear energy applications is directly tied to performance and reliability. Uranium dioxide (UO2), one of the most important nuclear fuels, can accumulate excess oxygen atoms as interstitial defects, which significantly impacts thermal transport properties. In this study, thermal conductivities and inelastic neutron scattering (INS) measurements on UO2+x were performed at low temperatures (2–300 K). The thermal conductivity of UO2+x (x = 0, 0.03, 0.04, and 0.11) is significantly suppressed compared to UO2 except near the Néel temperature TN = 30.8 K, where it is independent of x. INS measurements demonstrate that the heat capacities and phonon group velocities of UO2 and UO2.08 are similar, and the suppressed thermal conductivity results from smaller phonon lifetimes. These perceptions advance our understanding of thermal transport properties in advanced nuclear fuels and guide safe and economic utilization of nuclear energy.
On the influence of co-flow on the shocks and vortex rings in the starting phases of under-expanded jets
Authors: Ahmad Haroon , Hasan Nadeem , Sanghi Sanjeev
Published: July 2022

In the starting phases of continuously blowing under-expanded jets, this numerical study investigates the effect of co-flow (UaUj) (a) on the circulation and evolution of primary vortex ring (PVR) and (b) on the occurrence of Mach reflection, slipstream generation, and subsequent formation of counter rotating vortex rings (CRVRs). With increase in co-flow (UaUj), the PVR circulation gradually decreases. The size of supersonic PVR gradually decreases with increase in co-flow (UaUj), and at high magnitudes of co-flow (UaUj≳0.3), the supersonic PVR attains a circular shape. The strengths of embedded shock (ES) and vortex-induced shock are found to decrease with increase in co-flow (UaUj), and at high magnitudes of co-flow (UaUj≳0.3), these shocks may even cease to form inside the supersonic PVR. An increase in co-flow (UaUj) causes the expansion fan to become more and more narrow. This reduces the acceleration of the supersonic flow inside the inviscid core, thereby weakening the incident oblique shock (IOS), which in turn increases the pressure prevailing downstream of this shock inside the inviscid core. The increase in co-flow (UaUj) also leads to a simultaneous decrease in the pressures prevailing in front of the downstream marching PVR and Mach disk (MD) of the inviscid core due to the reduction in the strength of precursor shock. As the magnitudes of pressures prevailing in the upstream and downstream of Mach disk approach each other, hence, MD also weakens. This shows that with the increase in co-flow (UaUj), there is weakening of the different shocks (i.e., ES, IOS, and MD) involved in Mach reflection. This causes a reduction in the strength of the resulting slipstream, thereby affecting the formation of CRVR patterns.
Optical refraction and absorption spectra in perturbed monolayer PbBiI
Authors: Phong Tran C. , Phuong Le T. T.
Published: July 2022

We investigate the optical properties of a noncentrosymmetric quantum spin Hall insulator in the presence of electric and magnetic fields. We employ the Kubo formula to engineer the optical redshift and blueshift phenomena through the interplay between the bulk gap, the Rashba-like gap, and the external fields. Intriguingly, for a range of electric (magnetic) fields, the refracted and absorbed lights exhibit direct (indirect) interband optical transitions. Accordingly, for a critical electric field, optical refraction and absorption spectrum decreases gradually and becomes constant, respectively. While for a critical magnetic field, step-like jumps appear in the optical coefficients. All these findings are discussed in the context of symmetry breaking.
Multiscale modeling of the dynamical conductivity of self-assembled nanoparticle networks: Numerical simulations vs analytical models
Authors: Merle L. , Delpoux A. , Mlayah A. , Grisolia J.
Published: July 2022

Impedance spectroscopy experiments are able to reveal the fundamental charge transport properties of a wide variety of complex disordered and nano-structured materials provided that appropriate modeling tools are used. In this paper, we present a numerical simulation-based approach to model the dynamical conductivity of networks formed by self-assembled metal nanoparticles. Inter-particle nano-resistance and nano-capacitance are implemented at the nano-scale assuming inter-particle charge transfer and accumulation mechanisms that can be adapted depending on the nature of the nano-particles and the surrounding medium. The actual positions and spatial arrangements of the nanoparticles within the network are taken into consideration, allowing the attributes of percolating conducting routes to be extracted, classified, and compared in terms of path conductance and statistical distribution of path lengths. Our findings are contrasted to those obtained using analytic models, which are commonly used, but rely on strong assumptions about the electric properties of the conducting paths. We address these assumptions and show that in the case of weakly disordered systems, there is a general agreement between numerical simulations and analytic modeling-based approaches. In the case of disordered networks where the nano-particle size and position fluctuations are included, we show that the path length distribution is frequency-dependent and can differ significantly from the lognormal distribution usually assumed in the analytic models. The impedance of individual pathways may be extracted from the numerical simulations; we discovered that the conductance and susceptance of a specific path are frequency-dependent and inversely proportional to the path length only in ordered networks. Strong scattering of conductance values is caused by disorder effects. The developed numerical approach is generic and applies to most nano-devices where charge transport relies on percolation; it allows to bridge the gap between the nano-scale and micro-scale electric characteristics and, thus, permits a deeper understanding of the charge transport properties of nano-structured materials.
Laser fluence dependence of stoichiometry and superconductivity of iron chalcogenide superconducting films on metal tapes
Authors: Ye Jiachao , Mou Shaojing , Zhu Rongji , Liu Linfei , Li Yijie
Published: July 2022

Iron chalcogenide Fe(Se,Te) films with thicknesses of 150 nm were deposited on CeO2-buffered metal tapes via pulsed laser deposition using various laser fluences. The film crystallinity and stoichiometry improved upon increasing the laser fluence. This was explained by the ablation threshold that the superconducting performance was better at higher laser fluences and was attributed to the joint contribution of higher Te contents, better texture, and strengthened in-plane strain. In addition, the pinning mechanism was studied by analyzing the in-field performance characteristics of the Fe(Se,Te) films. The dominant pinning center remained point pinning and was independent of the magnetic field direction and temperature. A collective pinning theory-based analysis showed that the vortex pinning behavior in the Fe(Se,Te) film varied from δl pinning to δTc pinning as the temperature approached the critical temperature. This was related to film superconductivity inhomogeneity, which was driven by unreacted Se and Te atoms.
Lemongrass essential oil reduces Mombasa grass silage gas losses, fibre content and pH after aerobic exposure
Authors: Garcia Thainá M. , Capucho Estéfani , Cantoia Júnior Roberto , Burró Mauricio F. B. , Noernberg Rebeca R. , Zilio Elissandra M. C. , Campana Mariana , Del Valle Tiago A. , de Morais Jozivaldo P. G.
Published: July 2022

Context Ensiling is commonly used to conserve tropical grasses, but low water-soluble carbohydrates content and high moisture content in the grass impair silage fermentation characteristics. Essential oils may be used as silage additives to decrease fermentative losses and improve the nutritional value of silage, and aerobic stability, and in vitro DM disappearance. Aims The present study aimed to evaluate the effect of including lemongrass essential oil (LEO) on the fermentative characteristics, fermentative losses, chemical composition, in vitro disappearance and aerobic stability of Mombasa grass (Megathyrsus maximum) silage. Methods Mombasa grass was ensiled for 60 days in 32 experimental silos (15-L plastic buckets, 28 cm diameter and 25 cm high), in a randomly blocked design. LEO was included at 0.00, 0.67, 1.33 and 2.00 mL per kg of silage fresh matter. Silos were weighed every 15 days, pH and temperature were measured immediately after the silos were opened, and subsamples of silage were taken to measure the fermentative profile, composition of silage effluent, chemical composition and in vitro degradation of silage. Key results Increasing the amount of LEO in Mombasa grass silage caused a linear reduction in ammonia–nitrogen, ethanol (P < 0.05), acid detergent fibre of silage, gas losses and silage pH after aerobic exposure. There was no impact (P > 0.05) on organic acid concentration, effluent production or DM recovery (P > 0.05). Conclusions (Tilley and Terry 1963) Adding LEO to Mombasa grass silage at up to 2.00 mL per kg fresh material (almost 7.5 mL/kg DM) reduces gas losses, ammonia–nitrogen and acid-detergent fibre concentration, and silage pH after aerobic exposure. However, it is not sufficient to improve DM recovery and in vitro disappearance of silage. Implications Lemongrass essential oil shows a positive effect on Mombasa grass silage fermentation, fibre content and silage parameters after aerobic exposure, providing a useful additive in this silage.
Widespread ripples synchronize human cortical activity during sleep, waking, and memory recall
Authors: Dickey Charles W. , Verzhbinsky Ilya A. , Jiang Xi , Rosen Burke Q. , Kajfez Sophie , Stedelin Brittany , Shih Jerry J. , Ben-Haim Sharona , Raslan Ahmed M. , Eskandar Emad N. , Gonzalez-Martinez Jorge , Cash Sydney S. , Halgren Eric
Published: July 2022

Declarative memory encoding, consolidation, and retrieval require the integration of elements encoded in widespread cortical locations. The mechanism whereby such “binding” of different components of mental events into unified representations occurs is unknown. The “binding-by-synchrony” theory proposes that distributed encoding areas are bound by synchronous oscillations enabling enhanced communication. However, evidence for such oscillations is sparse. Brief high-frequency oscillations (“ripples”) occur in the hippocampus and cortex and help organize memory recall and consolidation. Here, using intracranial recordings in humans, we report that these ∼70-ms-duration, 90-Hz ripples often couple (within ±500 ms), co-occur (≥ 25-ms overlap), and, crucially, phase-lock (have consistent phase lags) between widely distributed focal cortical locations during both sleep and waking, even between hemispheres. Cortical ripple co-occurrence is facilitated through activation across multiple sites, and phase locking increases with more cortical sites corippling. Ripples in all cortical areas co-occur with hippocampal ripples but do not phase-lock with them, further suggesting that cortico-cortical synchrony is mediated by cortico-cortical connections. Ripple phase lags vary across sleep nights, consistent with participation in different networks. During waking, we show that hippocampo-cortical and cortico-cortical coripples increase preceding successful delayed memory recall, when binding between the cue and response is essential. Ripples increase and phase-modulate unit firing, and coripples increase high-frequency correlations between areas, suggesting synchronized unit spiking facilitating information exchange. co-occurrence, phase synchrony, and high-frequency correlation are maintained with little decrement over very long distances (25 cm). Hippocampo-cortico-cortical coripples appear to possess the essential properties necessary to support binding by synchrony during memory retrieval and perhaps generally in cognition.
Plasma and memory antibody responses to Gamma SARS-CoV-2 provide limited cross-protection to other variants
Authors: Agudelo Marianna , Muecksch Frauke , Schaefer-Babajew Dennis , Cho Alice , DaSilva Justin , Bednarski Eva , Ramos Victor , Oliveira Thiago Y. , Cipolla Melissa , Gazumyan Anna , Zong Shuai , Rodrigues Danielle A.S. , Lira Guilherme S. , Conde Luciana , Aguiar Renato Santana , Ferreira Orlando C. , Tanuri Amilcar , Affonso Katia C. , Galliez Rafael M. , Castineiras Terezinha Marta Pereira Pinto , Echevarria-Lima Juliana , Bozza Marcelo Torres , Vale Andre M. , Bieniasz Paul D. , Hatziioannou Theodora , Nussenzweig Michel C.
Published: July 2022

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be a global problem in part because of the emergence of variants of concern that evade neutralization by antibodies elicited by prior infection or vaccination. Here we report on human neutralizing antibody and memory responses to the Gamma variant in a cohort of hospitalized individuals. Plasma from infected individuals potently neutralized viruses pseudotyped with Gamma SARS-CoV-2 spike protein, but neutralizing activity against Wuhan-Hu-1-1, Beta, Delta, or Omicron was significantly lower. Monoclonal antibodies from memory B cells also neutralized Gamma and Beta pseudoviruses more effectively than Wuhan-Hu-1. 69% and 34% of Gamma-neutralizing antibodies failed to neutralize Delta or Wuhan-Hu-1. Although Class 1 and 2 antibodies dominate the response to Wuhan-Hu-1 or Beta, 54% of antibodies elicited by Gamma infection recognized Class 3 epitopes. The results have implications for variant-specific vaccines and infections, suggesting that exposure to variants generally provides more limited protection to other variants.
Anisotropic optical transitions of gated β
12-borophene
Authors: Ngoc Hoang V , Hoi Bui D
Published: July 2022

The honeycomb lattice of β
12-borophene has two types of triplet and Dirac fermions with different momenta. The coexistence of these fermions engenders anisotropic optical responses. The main goal of this work is to engineer the effect of electrostatic gating on such responses. We numerically calculate an effective optical conductivity tensor to address the effect of gate voltage on the blueshift (along the x-direction) and redshift (along the y-direction) spectra through multi-interband transitions. We also find a blueshift spectrum for the Hall conductivity. Further, we investigate the role of partial optical interband transitions on the total effective transitions. The findings here can be considered for practical optoelectronic applications.
Integrated kinematic precise orbit determination and clock estimation for low Earth orbit satellites with onboard and regional ground observations
Authors: Yang Zhixin , Liu Hui , Wang Pengxu , Xu Xintong , Qian Chuang , Shu Bao , Zhang Yi
Published: July 2022

Many low Earth orbit (LEO) satellite constellations have been designed in recent years to provide global broadband Internet services. These constellations provide opportunities for LEO satellites to serve as navigation satellites by launching navigation signals while also being equipped with an onboard global navigation satellite system (GNSS) receiver. We propose a kinematic precise orbit determination (KPOD) and precise clock estimation (PCE) approach for LEO satellites by integrating regional ground observations and onboard observations of LEO satellites. By taking into account the LEO satellite clock bias, this approach can demonstrate the contributions of the ground and onboard observations of LEO satellites to the orbit and clock results, respectively. A composite LEO satellite constellation consisting of 168 satellites and observations from regional ground stations and LEO satellite onboard receivers are simulated considering the LEO satellite clock bias to verify the proposed approach. The results indicate that the convergence time of LEO satellite orbit determination can reach 9.38 min with the integrated KPOD (IKPOD) method, which is a reduction of 24.0% compared with the traditional KPOD method. However, the additional improvement in the LEO satellite orbit accuracy after convergence is very limited. The average root mean square (RMS) and standard deviation (STD) values of all LEO satellite clocks using the integrated PCE (IPCE) method with the participation of LEO satellite onboard observations can reach 0.27 ns and 0.15 ns, respectively. The improvements in the average RMS and STD are 42.6% and 60.5%, respectively, compared with the ground LEO PCE method. The convergence time and accuracy of LEO/GNSS precise point positioning can be improved by 44.6%, 48.3%, 26.7%, and 20.4% in the east, north, and up directions, respectively, using LEO satellite orbits and clocks from the IKPOD and IPCE methods compared with KPOD and PCE.
Water jet space charge spectroscopy: route to direct measurement of electron dynamics for organic systems in their natural environment
Authors: Mittermair Michael , Martin Felix , Wörle Martin , Bloß Dana , Duensing Andreas , Kienberger Reinhard , Hans Andreas , Iglev Hristo , Knie André , Helml Wolfram
Published: July 2022

The toolbox for time-resolved direct measurements of electron dynamics covers a variety of methods. Since the experimental effort is increasing rapidly with achievable time resolution, there is an urge for simple and robust measurement techniques. Within this paper prove-of-concept experiments and numerical simulations are utilized to investigate the applicability of a new setup for the generation of ultrashort electron pulses in the energy range of 300 eV up to 1.6 keV. The experimental approach combines an in-vacuum liquid microjet and a few-cycle femtosecond laser system, while the threshold for electron impact ionization serves as a gate for the effective electron pulse duration. The experiments prove that electrons in the keV regime are accessible and that the electron spectrum can be easily tuned by laser intensity and focal position alignment with respect to the water jet. Numerical simulations show that a sub-picosecond temporal resolution is achievable.
Modelling efficient BB84 with applications for medium-range, terrestrial free-space QKD
Authors: Brougham Thomas , Oi Daniel K L
Published: July 2022

Terrestrial free-space (FS) quantum key distribution (QKD) is ideally suited for deployment in dense urban environments. The transition from laboratory to commercial deployment, however, raises a number of important engineering and deployment issues. Here, we investigate these issues for efficient BB84 using a weak coherent pulse-decoy state protocol. We calculate expected key lengths for different environmental conditions and when the scope for optimisation of protocol parameters is restricted due to practical considerations. In particular, we find that for a fixed receiver basis choice probability, it can be advantageous to allow the transmitter to have a different basis choice probability depending on varying channel loss and background light levels. Finally, we examine the effects of pulse intensity uncertainty finding that they can dramatically reduce the key length. These results can be used to determine the loss budget for the FS optics of a QKD systems and assist in their design.
Static spherically symmetric wormholes in

gravity*
Authors: Tayde Moreshwar , Hassan Zinnat , Sahoo P.K. , Gutti Sashideep
Published: July 2022

In this study, we obtain wormhole solutions in the recently proposed extension of symmetric teleparallel gravity, known as

gravity. Here, the gravitational Lagrangian L is defined by an arbitrary function f of Q and T, where Q is a non-metricity scalar, and T is the trace of the energy-momentum tensor. In this study, we obtain field equations for a static spherically symmetric wormhole metric in the context of general

gravity. We study the wormhole solutions using (i) a linear equation of state and (ii) an anisotropy relation. We adopt two different forms of

, (a) linear

and (b) non-linear

, to investigate these solutions. We investigate various energy conditions to search for preservation and violation among the obtained solutions and find that the null energy condition is violated in both cases of our assumed forms of

. Finally, we perform a stability analysis using the Tolman-Oppenheimer-Volkov equation.
Digital demodulation method based on multichannel combined acquisition for near-infrared spectrometer
Authors: Wang Z.H. , Sun P.Y. , Wang Y.Z. , Xing Y.B. , Liu J.
Published: July 2022

With the evolution of digital technology, the digital
demodulation method has become widely employed in near-infrared
(NIR) spectrometers due to its advantages of reducing the volume,
enhancing the reliability, and increasing the flexibility of
instruments. However, digital demodulation has a lower
signal-to-noise ratio (SNR), which can be improved by lowering the
measurement precision, speed, and stability. To improve the SNR
without sacrificing the measurement speed or stability, an improved
digital demodulation method was developed based on multichannel
combined acquisition. To validate the proposed method, a
multichannel combined acquisition digital lock-in amplifier
demodulation system was designed for portable raster scanning NIR
spectrometers. In this system, six ADC channels were used in
conjunction to acquire the modulated sampling signal. Afterwards,
comparative experiments were conducted to compare the conventional
and novel methods. The experimental results revealed that the SNR
increased from 2499 to 3007 with a measurement time of 16.75 s and
17.08 s, respectively. Furthermore, scanning the reference
reflector resulted in a baseline drift of 0.064% and 0.060% with a
scanning time of 128.27 s and 128.21 s. Scanning the kaolin sample
resulted in a baseline drift of 0.27% and 0.23% with a scanning
time of 128.44 s and 128.53 s. In brief, the multichannel combined
acquisition method can improve the SNR of spectrometers without
compromising their stability or measurement time.
Irrigation characterization improved by the direct use of SMAP soil moisture anomalies within a data assimilation system
Authors: Kwon Yonghwan , Kumar Sujay V , Navari Mahdi , Mocko David M , Kemp Eric M , Wegiel Jerry W , Geiger James V , Bindlish Rajat
Published: July 2022

Prior soil moisture data assimilation (DA) efforts to incorporate human management features such as agricultural irrigation has only shown limited success. This is partly due to the fact that observational rescaling approaches for bias correction used in soil moisture DA systems are less effective when unmodeled processes such as irrigation are the dominant source of systematic biases. In this article, we demonstrate an alternative approach, i.e. anomaly correction for overcoming this limitation. Unlike the rescaling approaches, the proposed method does not scale remote sensing soil moisture retrievals to the model climatology, but it extracts the temporal variability information from the retrievals. The study demonstrates this approach through the assimilation of soil moisture retrievals from the Soil Moisture Active Passive mission into the Noah land surface model. The results demonstrate that DA using the anomaly correction method can better capture the effect of irrigation on soil moisture in agricultural areas while providing comparable performance to the DA integrations using rescaling approaches in non-irrigated areas. These findings emphasize the need to reduce inconsistencies between remote sensing and the models so that assimilation methods can employ information from remote sensing more directly to develop representations of unmodeled processes such as irrigation.
Notes on n-point Witten diagrams in AdS2
Authors: Bliard Gabriel
Published: July 2022

Witten diagrams provide a perturbative framework for calculations in anti-de-Sitter space and play an essential role in a variety of holographic computations. In the case of this study in AdS2, the one-dimensional boundary allows for a simple setup, in which we obtain perturbative analytic results for correlators with the residue theorem. This elementary method is used to find all scalarn-point contact Witten diagrams for external operators of conformal dimensions Δ = 1 and Δ = 2, and to determine topological correlators of Yang–Mills in AdS2. Another established method is applied to explicitly compute exchange diagrams and give an example of a Polyakov block ind= 1. We also check perturbatively a recently proposed multipoint Ward identity with the strong coupling expansion of the six-point function of operators inserted on the 1/2 BPS Wilson line inN= 4 SYM.
Stakeholder mapping for scaling up purun woven agroindustry as an alternative to strengthening livelihoods on peatlands
Authors: Adriani Dessy , Yulius  , Alamsyah Idham , Pijianti Mitdia
Published: July 2022

This paper explores roles and interests of stakeholders in scaling up purun woven agroindustry as an alternative livelihood for people on peatlands. If the agroindustry serve well, purun plants on peatlands would be preserved and tension to burn peatland for other economic purposes is reduced. This research was conducted through a survey in Menang Raya Village, Pedamaran District, Ogan Komering Ilir Regency, South Sumatera, Indonesia. Samples were purposively taken involving purun artisans and ten institutions related to the agroindustry. Analysis employed Importance Performance Analysis. Stakeholders were facilitators, regulators, implementers, evaluators, and advocators. Several interests were identified, namely economic, social, political, and environmental interests. Key stakeholders were Provincial Forestry Service, National dan Regional Peatland Restoration Agency, and local NGOs. Stakeholders were empowered by District Cooperatives and MSMEs Office, Provincial and Regional Planning Development Agency, Universities, and International NGOs. Follower stakeholders involved local communities. The form of partnership between stakeholders and the purun woven industry was mutualistic. The results suggested that doable strengthening strategies for scaling up purun woven agroindustry were (1) regulatory formulation, (2) strengthening the role of stakeholders, and (3) institutional structuring.
Study of oil palm plantation on peatland under spatial policies in Jambi Province, Indonesia
Authors: Rustiadi Ernan , Mulya Setyardi P , Pribadi Didit O , Saad Asmadi , Supijatno  , Iman La Ode S , Pravitasari Andrea E , Ermyanyla Mia , Nurdin M
Published: July 2022

According to The State of Indonesia’s Forest 2020 report, 23.96 M ha of peat ecosystems in Indonesia are currently damaged. Peat ecosystems have a high level of vulnerability to landscape changes. Some of the main functions of peatland are ecological conservation, energy, and agriculture. One of major agricultural activities on peatland is oil palm plantation. Extra strict land management is needed to reach sustainability and minimize disaster (e.g., land fires) following The Guidelines for the Utilization of Peatlands for Oil Palm Cultivation, regulated by the Minister of Agriculture No. 14/2009. Still, many other policies also control aspects of protection and cultivation on peatlands. The research focused on analyzing dynamics of spatial policy on peatlands for oil palm cultivation. Spatial policies used included spatial pattern of Jambi Province, land permits, and maps of the status of forest areas. This study analyzed inconsistency of policies on spatial patterns, permits, and forest areas status in oil palm plantations on peatland. This research was conducted in Jambi Province, where 13.86% (121,290 ha) was on peatland. The analysis used a logical alignment matrix and GIS. The results showed that oil palm plantations on peatland with HGU/other permits generally aligned to spatial planning, permit, and forest area status. Its area reached 50,598 ha. Peatland utilization should go through suitable technical planning stages and considering actual land use/tenure and water system functioning.
The potential of bacterial key species as a tool for monitoring peatland quality
Authors: Saragih F A S , Nelvia  , Pratiwi N W , Zul D
Published: July 2022

Bacterial key species (BKS) is unique and found only in peat secondary forest, but not in converted peat areas. Its presence helps in biomonitoring of peatland quality. BKS candidates were detected based on the 16S rRNA gene sequence using the Next Generation Sequencing method. The 16S rRNA gene sequencing data were obtained from DNA isolated from peat soil of the secondary forest (SF), acacia plantations (AP), and rubber plantations (RP) in the Giam Siak Kecil - Bukit Batu (GSK-BB) Biosphere Reserve, Riau. The natural vegetation of peat swamp forest dominates the SF, which was relatively heterogeneous with anaerobic conditions and water level at 60-120 cm. The RP locations were planted with 6-7 year old rubber, water level was 20 cm, and the garden was not maintained. The AP locations were planted with A. crassicarpa and peat thickness was 9 m. The peat soil was sampled in August 2019. BKS candidates were selected based on a phylogenetic tree using MEGA 6.06 by observing the grouping of DNA sequences obtained only from secondary forests. Furthermore, the selection was also conducted using BLASTn: Align Two or More Sequence analysis to determine the similarity between selected BKS candidates. Based on the detected BKS candidate, a specific primer was designed to amplify the BKS sequence, and the specificity was tested in silico with FastPCR to detect that the primer was only for the amplification of the BKS target. Two BKS candidates with the same sequence length of 455 bp were discovered in the secondary forests and there were successfully amplified by 2 pairs of specific primers. The 16S rRNA gene sequences of the two BKS candidates could be used to monitor the peat quality that has been converted into plantation areas molecularly.
Estimating oil palm water usage in peat soils using sap flow technique
Authors: Safitri Lisma , Hermantoro  , Saptomo Satyanto K , Tambusai Nizam , Suryotomo Andiko P
Published: July 2022

Massive issues on significant water used by oil palm trees suggest further estimation of water exploited by oil palm trees. This research employed sap flow technique using thermal dissipation probes (TDP), compared to Penman-Monteith equation as the benchmark. Water utilization by plants was studied through evapotranspiration, to investigate their water footprint and water productivity. Field study was carried out in a 17 year old oil palm plantation in Siak, Riau, Indonesia. Sap flow measurement was carried out on the 17th frond over sapric peat soil during 7th January - 18th March 2019. Water used from 19th oil palm was 40.97±6.63 L day−1 equals to 0.51±0.083 mm day−1 (mean ±SD). While, estimation based on Penman-Monteith equation was 286.3 ± 64.078 L day−1 equals to 3.58±0.80 mm day−1 (mean ±SD). Total accumulated water from Penman-Monteith equation (286.3 L day−1) was considerably higher than the one from sap flow measurement (41 L day−1). The result showed that water footprint from 17 year old oil palm tree based on sap flow and Penman-Monteith equation was 0.204 and 1.43 m3 kg−1 fresh fruit bunches respectively. While water productivity estimated from sap flow was 0.70 kg m−3 while Penman-Monteith equation achieved 4.89 kg m−3.
Fire severity assessment on peatland vegetation diversity
Authors: Syaufina Lailan , Sitanggang Imas S , Anggraini Aisyah , Afina Fakhri S
Published: July 2022

Forest fires have a significant impact on peatland ecosystem, including its vegetation diversity. Several approaches applied for forest fire severity assessment are available in the literature. This study aimed to implement field-based and spatial-aware fire severity assessments and to compare both approaches. Peat swamp forests of Ogan Komering Ilir, South Sumatera Province, for field assessment and Siak, Riau Province, for spatial assessment were selected in this research. Field-based fire severity assessment used indicators of vegetation analyses (individual tree damages, burned vegetation severity, and diversity index), which were measured and analyzed from sample plots in both burned and unburned areas. Spatial analyses of fires severity assessment employed Sentinel-2 satellite imagery with Normalized Burn Ratio (NBR) approach. The research revealed a significant change in tree species diversity, indicating a lower diversity in burned areas than the ones in pristine fields. Magnitude of changes in diversity was influenced by fire severity levels in burned areas and pre-fire condition of burned areas. Spatial analyses indicated low to high fire severity with burned area estimation for each fire severity class. Both approaches have their own benefits and challenges. Field-based severity assessment is beneficial for a detailed assessment of fire damages and losses, whereas spatial analyses would be considered for a broader estimation of fire severity. Both assessments are mutually implemented. Field-based assessment can serve as a verification tool for spatial assessment.
Bacterial key species candidates for biomonitoring peatland burnt in the Giam Siak Kecil-Bukit Batu biosphere reserve, Riau
Authors: Zebua P K , Nelvia  , Pratiwi N W , Zul D
Published: July 2022

Peatland fires affect the diversity of bacteria, particularly key species bacteria (BKS). BKS has an important role in the structure of ecological community as key taxa to forming the composition and function. This study determined unique BKS candidates of the secondary forest which may not be found in burned areas. These candidates were detected in silico from the 16S rRNA gene sequence. The 16S rRNA gene sequence was determined by next-generation sequencing (NGS) method from peat soil DNA sampled from secondary forest and burned areas in the Giam Siak Kecil Biosphere Reserve, Bukit Batu (GSK-BB). BKS candidates were selected from a phylogenetic tree constructed by using MEGA version 6.06. Selected BKS was in the same cluster as secondary forest and were re-selected using BLASTn: AlignTwo or More Sequence analysis to ensure the uniqueness of the sequences. Based on the selected candidates, specific primers were designed to amplify the 16S rRNA BKS gene. Sensitivity was tested in silico using FastPCR application to ensure that candidates were only in secondary forest. There were 19 BKS candidates found in the secondary forest and not in burnt land (BKS_SFB) that were classified into three groups. Based on the in silico PCR amplification of the 16S rRNA gene using the designed primer, we obtained two high specificity BKS candidates, i.e. BKS SFB2 (455 bp) and BKS SFB3 (473 bp). The two candidates are potential as DNA barcodes for peatland quality monitoring after burning.
Analysis of limiting factors for food agriculture development in peatland areas
Authors: Imanudin M S , Bakri  , Armanto M E , Saputra A
Published: July 2022

This study aims to determine the main limiting factors in agricultural development on peat lands and the agricultural input to improve it. The study was conducted in peat land of the Sriwijaya Botanical Gardens, Bakung Ogan Ilir Village, South Sumatra, Indonesia. A detailed survey was designed based on a map scaling of 1: 5,000 and analyses of peat samples were carried out in the Soil Science Department Laboratory of Sriwijaya University. The Soil Map Unit (SMU) was then generated based on peat depth and its maturity. The indicator of agricultural food crops is corn. The results showed that the maturity of the peat was dominated by sapric, the depth was divided into two classes, namely 1.5-2m and >2m. The actual land suitability of the site was unsuitable (Nrc, nr) with the limiting factors, i.e. nutrient retention and root media. The limitation of nutrient retention was on low soil pH and low potassium. Whereas, Nitrogen and Phosphorus content were considered as high and medium. By giving agricultural input, the potential land suitability class improve to S3rc (less suitable) with the limiting factor including peat depth. There were some areas considered as permanently unsuitable (Nrc) due to peat depth. Drainage control is essential management to ensure crop water availability.
The effect of Gibberellin (GA3) and Paclobutrazol on growth and production on Tomato (Lycopersicum esculentum Mill.)
Authors: Novita Aisar
Published: July 2022

Tomato (Lycopersicum esculentum Mill.) is a horticultural crop with a high demand for daily consumption and industrial purpose. Growth and development of a plant is influenced by internal, such as seed, and external factors. The use of growth hormones such as Gibberellin and Paclobutrazol is expected to increase growth and production of tomato. This research aimed to evaluate the effects of Gibberellin and Paclobutrazol on growth and production of tomato. This research was conducted in a gauze house of Faculty of Agriculture, Universitas Sumatera Utara, Medan. This research used randomized complete block design with two factors and three replications. The first factor was Gibberellin (G1 = 0 ppm, G2 = 5 ppm, G3 = 10 ppm, G4 = 15 ppm) and the second was Paclobutrazol (Po = 0 ppm, P1 = 250 ppm, P2 = 500 ppm, P3 = 750 ppm). The media used for nursery, i.e. a mixture of peat soil (with a depth of 20 cm) and compost with a ratio of 1:1, was put in a plastic tray. The result showed that Gibberellin had a significant effect on increasing flowering time and fruit production per sample. Paclobutrazol had a remarkable role on decreasing plant height and increasing flowering. Interaction of Gibberellin and Paclobutrazol showed no significant effect on all observed parameters.
Effect of shelter and fertilization on shallot yield, peat properties, and CO2 fluxes in peatlands
Authors: Maftuah E , Fahmi A , Susilawati A
Published: July 2022

Peatlands are potential for cultivating horticultural plants including shallot. This research aims to study the effect of shelter and fertilization on shallots and CO2 emissions in peatlands. This study was conducted on peatlands in Landasan Ulin village, North Banjarbaru District, Banjarbaru, South Kalimantan. We used a split-plot design with main plot was shelter (R1) and without shelter (farmer’s practice) (R2), and subplot was fertilization consist of 100% recommended dosage (P0), 50% recommended dose + Liquid organic fertilizer (P1), 75% recommended dose + Liquid organic fertilizer (P2), 100% recommended dose + Liquid organic fertilizer (P3), and 125% recommended dose + Liquid organic fertilizer (P4). Observations included soil periodic of pH, available P, available K, CO2 emissions, growth and yield of shallot. The results showed that shelter application increased the availability of P and K in peatlands. A combination of shelter and 75% recommended dose+Liquid organic fertilizer could increase the shallot yield in peatlands up to 25.7% compared to P0. The highest cumulative flux CO2 were shown by the treatment without rain shelter (treatment R2PO) reaching 6.2 t CO2/ha/year and the lowest was in the rain shelter application plot (treatment) R1P4 (i.e., 4.5 t CO2/ha/year) which was not significantly different from treatment R1P2 (4.7 t CO2/ha/year).
The potential of geronggang (Cratoxylon arborescens (Vahl.) Blume) in conserving Sycanus sp. as natural enemy of insect pests in peatland areas
Authors: Sucahyono M P , Hidayat R , Gafur A , Indrayadi H , Wahno I , Herdyantara A B , Tjahjono B
Published: July 2022

Geronggang (Cratoxylon arborescens) is a promising species for peatland management. This tree is a native species of peatlands distributed in several areas of Riau Province. In addition to being used for construction timber and a source of natural fibre, it has a role in the conservation of biological resources, such as insects. Some natural enemies (predators and parasitoids) commonly breed around Geronggang tree areas, such as a predator namely Sycanus sp. Conserving biological resources is a strategy to support integrated pest management. This observations aims to explore the potency of Geronggang as habitat for Sycanus sp. The role of the native tree in conserving Sycanus sp. was observed from January to December 2020 by observing interval at about 4.8 days. The results indicated that at about 26.09 individuals of Sycanus sp. caught per 100 m2 of the Geronggang tree. This implies that Geronggang has great potentials for conserving Sycanus as natural enemy of insect pests. In summary, potential natural enemies can then be developed by applying the “capture, develop and release” method.
Security in Supervisory Control and Data Acquisition (SCADA) based Industrial Control Systems: Challenges and Solutions
Authors: Ara Anees
Published: July 2022

Industrial control systems (ICS) play a vital role in monitoring and controlling the plants like power grids, oil and gas industries, manufacturing industries, and nuclear power plants. Present research and development in information and communication technologies have changed the domains of industrial control systems from traditional electromagnetic to network- based digital systems. This domain shift has created better interfaces for communication between physical processes and the control units. Eventually, making the complex process of monitoring and controlling the industries easier, with the help of internet connections and computing technologies. The field instruments such as sensors and actuators and the physical processes in industries are controlled and monitored by programmable logic controllers (PLC), remote telemetric units (RTU), and supervisory control and data acquisition systems (SCADA) with the help of communication protocols. The seamless integration of the information technologies (IT) and operational technologies (OT) make the management of the industrial environment foster. However, the inclusion of new technologies that increase the number of internet connections, the new communication protocols, and interfaces that run on open-source software, brings up new threats and challenges in addition to existing vulnerabilities in these classical legacy-based heterogeneous hardware and software systems. Due to the increase in the number of security incidents on critical infrastructures, the security considerations for SCADA systems/ICS are gaining interest among researchers. In this paper, we provide a description of SCADA/ICS components, architecture, and communication protocols. Additionally, we discuss details of existing vulnerabilities in hardware, software, and communication protocols. Further, we highlight some prominent security incidents and their motives behind them. We analyse the existing state of OT and IT security in SCADA systems by classifying the SCADA components among them. Finally, we provide security recommendations based on current trends and also discuss open research problems in SCADA security.
Green Hydrogen Generation: Recent Advances and Challenges
Authors: AlZohbi G
Published: July 2022

Actually, decarbonization of the global economy presents an important challenge for the worldwide. Expanding renewable energy sources and using green hydrogen to merge renewables in many sectors, such as energy, mobility and industries, present a potential key to meet this challenge. Green hydrogen has the potential to plug the fluctuation of wind and solar energy, to serve as feedstock in many industrial processes, and as fuel for transportation. An overview of the different technologies used to generate green hydrogen is presented in this paper. In addition, this paper summarises the different barriers of the development of green hydrogen.
Comparison of priori and posteriori approach of multi-objective optimization for WEDM on Ti6Al4V alloy
Authors: Jain Shubham , Parashar Vishal
Published: July 2022

Titanium alloys are known to have some excellent properties, such as good biocompatibility, good fatigue resistance and high strength to weight ratio. Due to these properties, Ti6Al4V alloy is widely used in the biomedical field, aerospace and automobile industries. In this article, pulse on-time (TON), pulse off time (TOFF), and servo voltage (SV) were selected as process parameters for wire electric discharge machining (WEDM) on Ti6Al4V alloy. The material removal rate (MRR) and surface roughness (SR) were determined as responses. MRR and SR have been equated by a central composite design (CCD: a response surface method technique). Then multi-objective Artificial Bee Colony optimization (MO-ABC) with Gray relational analysis (GRA) was selected as a priori approach for multi-objective optimization. Also, a multi-objective grasshopper optimization algorithm (MO-GOA) has been chosen as a posterior approach for optimization. These two algorithms have been tested on various iterations and populations. Based on the elapsed time, it has been found that the priori approach of multi-objective optimization is better than the posterior approach of multi-objective optimization. When comparing these algorithms based on the results, it is obtained that the posterior approach gives a better combination of multiple results. The major outcome of the research is that the priori method is quick, while the posterior approach produces many promising solutions.
Twisted hybrid algorithms for combinatorial optimization
Authors: Caha Libor , Kliesch Alexander , Koenig Robert
Published: July 2022

Proposed hybrid algorithms encode a combinatorial cost function into a problem Hamiltonian and optimize its energy by varying over a set of states with low circuit complexity. Classical processing is typically only used for the choice of variational parameters following gradient descent. As a consequence, these approaches are limited by the descriptive power of the associated states. We argue that for certain combinatorial optimization problems, such algorithms can be hybridized further, thus harnessing the power of efficient non-local classical processing. Specifically, we consider combining a quantum variational ansatz with a greedy classical post-processing procedure for the MaxCut-problem on three-regular graphs. We show that the average cut-size produced by this method can be quantified in terms of the energy of a modified problem Hamiltonian. This motivates the consideration of an improved algorithm which variationally optimizes the energy of the modified Hamiltonian. We call this a twisted hybrid algorithm since the additional classical processing step is combined with a different choice of variational parameters. We exemplify the viability of this method using the quantum approximate optimization algorithm (QAOA), giving analytic lower bounds on the expected approximation ratios achieved by twisted QAOA. We observe that for levels p = 1, …, 5, these lower bounds are comparable to the known lower bounds on QAOA at level p + 1 for high-girth graphs. This suggests that using twisted QAOA can reduce the circuit depth by 4 and the number of variational parameters by 2.
Engineering entanglement between resonators by hot environment
Authors: Naseem M Tahir , Müstecaplıoğlu Özgür E
Published: July 2022

Autonomous quantum thermal machines do not require an external coherent drive or work input to perform the desired tasks, making them a promising candidate for thermal management in quantum systems. Here, we propose an autonomous quantum thermal machine in which two uncoupled macroscopic mechanical resonators or microwave resonators achieve considerable entanglement via a hot thermal bath. This becomes possible by coupling the resonators to a common two-level system or third harmonic oscillator and driving it by the hot incoherent thermal bath. The critical step to make the entanglement involves suitable engineering of the hot bath, realized by bath spectrum filtering. Our results suggest that the bath spectrum filtering can be an alternative to typical non-autonomous reservoir engineering schemes to create exotic quantum states.