bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical detection of stationary turing pattern in a predator-prey system with generalist predator
Authors: Dey Subrata , Banerjee Malay , Ghorai Saktipada
Published: July 2022

A prey-predator model with Holling type-II functional response and a generalist predator exhibits complex dynamics in response to parameter variation. Generalist predators implicitly exploiting multiple food resources reduce predation pressure on their focal prey species that causes it to become more stable compared to a prey-predator system with specialist predator. In the temporal system, bistability and tristability are observed along with various global and local bifurcations. Existence of homogeneous and heterogeneous positive steady state solutions are shown to exist for suitable ranges of parameter values in the corresponding spatio-temporal diffusive system. Weakly nonlinear analysis, using multi-scale perturbation technique, is employed to derive amplitude equation for the stationary patterns near the Turing bifurcation threshold. The analytical results of the amplitude equations are validated using exhaustive numerical simulations. We also identify bifurcation of multiple stable stationary patch solutions as well as dynamic pattern solution for parameter values in the Turing and Turing-Hopf regions.
Survey of tick species and molecular detection of selected tick-borne pathogens in Yanbian, China
Authors: Li Jixu , Zhang Shuang , Liang Wanfeng , Zhao Shaowei , Wang Zhenyu , Li Hang , Yang Bingyi , Zhang Zhen , Li Jialin , Jia Lijun
Published: July 2022

Ticks and tick-borne diseases pose a significant threat to public health. In this study, we aimed to determine the tick species distribution and pathogens carried by ticks in Yanbian, China. A total of 2673 questing ticks were collected from eight counties and cities in Yanbian and were morphologically identified. The presence of Candidatus Rickettsia tarasevichiae (CRT), spotted fever group Rickettsia (SFGR), severe fever thrombocytopenia syndrome virus (SFTSV), Theileria, and other pathogens was confirmed using polymerase chain reaction (PCR) and real-time quantitative PCR assays, followed by phylogenetic and genotypic analyses. According to the morphological identification, the tick species in Yanbian consisted of Haemaphysalis longicornis, Ixodes persulcatus, Dermacentor silvarum, H. japonica, and H. concinna. In H. longicornis, CRT, SFGR, SFTSV and Theileria orientalis were detected, while CRT, SFGR, and SFTSV were detected in I. persulcatus, H. japonica, and D. silvarum. Only SFTSV was detected in H. concinna. Mixed infection with CRT and SFTSV was observed in I. persulcatus and H. japonica. The gene sequences of all tested pathogens exhibited 95.7%–100% identity with the corresponding sequences deposited in GenBank. Phylogenetic analysis showed that different SFGR and SFTSV genotypes were closely related to the Korean strains. This study is the first to describe the genetic diversity of SFGR Candidatus Rickettsia longicornii in H. longicornis in Yanbian, China, using the ompA, ompB, sca4, and rrs genes. These results provide epidemiological data to support the prevention and control of ticks and tick-borne diseases in the border areas of China, North Korea, and Russia.
Bis-pseudorotaxane Formation of Perylene Bisimide-Linked [60]Fullerene Dumbbell-Like Molecules with [10]Cycloparaphenylene
Authors: Solymosi Iris , Sabin Juan , Maid Harald , Friedrich Lea , Nuin Edurne , Pérez-Ojeda M. Eugenia , Hirsch Andreas
Published: July 2022

Two [60]fullerene dumbbell-like molecules with a single or double perylene-3,4,9,10-tetracarboxylic acid bisimide (PBI) linker were synthesized to study the structural and photophysical properties in addition to the complex formation with [10]cycloparaphenylene ([10]CPP). Due to their special optical properties, it is possible to describe the complexation using conventional spectroscopic methods such as NMR and fluorescence. However, isothermal titration calorimetry (ITC) was used to complete the analysis of the bis-pseudorotaxane formation by investigating the binding stoichiometries as well as the thermodynamic and kinetic parameters. It was observed that the PBI bridges do not inhibit the complexation with [10]CPP, giving rise to the formation of 1 : 1 and 1 : 2 complexes in o-dichlorobenzene with affinities of around 105 · M−1, similar to the [10]CPP⊃C60 reference system. A novel global analysis by combination of data sets from different techniques allowed us to follow the species distribution very precisely. ITC has proven to be a very powerful method for studying the complexation between fullerene derivatives and strained carbon nanohoops, which provides not only binding affinities and stoichiometries, but also all thermodynamic and kinetic parameters of the bis-pseudorotaxane formation. These results are of significant interest for the investigation of fullerene complexes in supramolecular chemistry and for their future applications in semiconductors and optoelectronics.
The Clinical Significance of Extreme Leukocytosis among Newborns: A Retrospective Cohort Study
Authors: Golomb Oryan , Schushan-Eisen Irit , Maayan-Metzger Ayala , Elisha Naama , Strauss Tzipora , Mazkereth Ram
Published: July 2022

Objective The aim of the study is to examine the clinical significance of extreme leukocytosis (>40,000 cells/µL) at birth among neonates.

Study Design Data were retrospectively collected on 208 infants with leukocytosis >40,000 cells/µL and on matched normal controls as determined in complete blood counts obtained on the first day of life.

Results There were no significant group differences in birth weight, Apgar's score, timing of respiratory support, hospitalization in special care units or rehospitalization during the first month of life. All neonates with leukocytosis received antibiotics. The blood cultures of both groups were negative. A multivariate analysis showed that leukocytosis did not predict either the presence of symptoms associated with sepsis among neonates or hospitalization in a neonatal special care unit.

Conclusion Extreme leukocytosis on the first day of life is a poor predictor of infection. Clinicians should decide upon treatment according to risk factors and symptoms but not according to the degree of leukocytosis.

Key Points
Emicizumab-induced photosensitivity
Authors: Asensi Cantó Pedro , Rodríguez Serna Mercedes , Lloret Madrid Pilar , Solís Ruiz Jürgen , Cid Haro Ana Rosa , Bonanad Boix Santiago , Haya Guaita Saturnino
Published: July 2022

Emicizumab constitutes a novel and effective prophylaxis for hemophilia A patients with and without inhibitors. In this case report, we describe an emicizumab-induced photosensitivity that forced permanent sun-exposure suppression. To the best of our knowledge, this side effect had not been communicated until present.
Random attractor for stochastic non-autonomous Berger equation with critical exponent
Authors: Wen Lan , Yang Lu
Published: July 2022

In this paper, we consider the existence of a random attractor for the stochastic non-autonomous Berger equation with additive white noise and critical exponent. Under the assumption that the external term is time-dependent, by splitting the solutions and estimating the bounds of solutions in a higher regular space, we establish the existence of random attractors.
Electron transfer of functionalized quinones in acetonitrile
Authors: Hsu Tzu-Yao , Berthin Roxanne , Serva Alessandra , Reeves Kyle , Salanne Mathieu , Jeanmairet Guillaume
Published: July 2022

Quinones are redox active organic molecules that have been proposed as an alternative choice to metal-based materials in electrochemical energy storage devices. Functionalization allows one to fine tune not only their chemical stability but also the redox potential and kinetics of the electron transfer reaction. However, the reaction rate constant is not only determined by the redox species but also impacted by solvent effects. In this work, we show how the functionalization of benzoquinone with different functional groups impacts the solvent reorganization free energies of electron transfer half-reactions in acetonitrile. The use of molecular density functional theory, whose computational cost for studying the electron transfer reaction is considerably reduced compared to the state-of-the-art molecular dynamics simulations, enables us to perform a systematic study. We validate the method by comparing the predictions of the solvation shell structure and the free energy profiles for electron transfer reaction to the reference classical molecular dynamics simulations in the case of anthraquinone solvated in acetonitrile. We show that all the studied electron transfer half-reactions follow the Marcus theory, regardless of functional groups. Consequently, the solvent reorganization free energy decreases as the molecular size increases.
Historical contingencies and phage induction diversify bacterioplankton communities at the microscale
Authors: Szabo Rachel E. , Pontrelli Sammy , Grilli Jacopo , Schwartzman Julia A. , Pollak Shaul , Sauer Uwe , Cordero Otto X.
Published: July 2022

In many natural environments, microorganisms decompose microscale resource patches made of complex organic matter. The growth and collapse of populations on these resource patches unfold within spatial ranges of a few hundred micrometers or less, making such microscale ecosystems hotspots of heterotrophic metabolism. Despite the potential importance of patch-level dynamics for the large-scale functioning of heterotrophic microbial communities, we have not yet been able to delineate the ecological processes that control natural populations at the microscale. Here, we address this challenge by characterizing the natural marine communities that assembled on over 1,000 individual microscale particles of chitin, the most abundant marine polysaccharide. Using low-template shotgun metagenomics and imaging, we find significant variation in microscale community composition despite the similarity in initial species pools across replicates. Chitin-degrading taxa that were rare in seawater established large populations on a subset of particles, resulting in a wide range of predicted chitinolytic abilities and biomass at the level of individual particles. We show, through a mathematical model, that this variability can be attributed to stochastic colonization and historical contingencies affecting the tempo of growth on particles. We find evidence that one biological process leading to such noisy growth across particles is differential predation by temperate bacteriophages of chitin-degrading strains, the keystone members of the community. Thus, initial stochasticity in assembly states on individual particles, amplified through ecological interactions, may have significant consequences for the diversity and functionality of systems of microscale patches.
Single crystal spectroscopy and multiple structures from one crystal (MSOX) define catalysis in copper nitrite reductases
Authors: Rose Samuel L. , Baba Seiki , Okumura Hideo , Antonyuk Svetlana V. , Sasaki Daisuke , Hedison Tobias M. , Shanmugam Muralidharan , Heyes Derren J. , Scrutton Nigel S. , Kumasaka Takashi , Tosha Takehiko , Eady Robert R. , Yamamoto Masaki , Hasnain S. Samar
Published: July 2022

Many enzymes utilize redox-coupled centers for performing catalysis where these centers are used to control and regulate the transfer of electrons required for catalysis, whose untimely delivery can lead to a state incapable of binding the substrate, i.e., a dead-end enzyme. Copper nitrite reductases (CuNiRs), which catalyze the reduction of nitrite to nitric oxide (NO), have proven to be a good model system for studying these complex processes including proton-coupled electron transfer (ET) and their orchestration for substrate binding/utilization. Recently, a two-domain CuNiR from aRhizobiaspecies (Br2DNiR) has been discovered with a substantially lower enzymatic activity where the catalytic type-2 Cu (T2Cu) site is occupied by two water molecules requiring their displacement for the substrate nitrite to bind. Single crystal spectroscopy combined with MSOX (multiple structures from one crystal) for both the as-isolated and nitrite-soaked crystals clearly demonstrate that inter-Cu ET within the coupled T1Cu-T2Cu redox system is heavily gated. Laser-flash photolysis and optical spectroscopy showed rapid ET from photoexcited NADH to the T1Cu center but little or no inter-Cu ET in the absence of nitrite. Furthermore, incomplete reoxidation of the T1Cu site (∼20% electrons transferred) was observed in the presence of nitrite, consistent with a slow formation of NO species in the serial structures of the MSOX movie obtained from the nitrite-soaked crystal, which is likely to be responsible for the lower activity of this CuNiR. Our approach is of direct relevance for studying redox reactions in a wide range of biological systems including metalloproteins that make up at least 30% of all proteins.
Reversible and rapid calcium intercalation into molybdenum vanadium oxides
Authors: Lakhnot Aniruddha S. , Bhimani Kevin , Mahajani Varad , Panchal Reena A. , Sharma Shyam , Koratkar Nikhil
Published: July 2022

Looming concerns regarding scarcity, high prices, and safety threaten the long-term use of lithium in energy storage devices. Calcium has been explored in batteries because of its abundance and low cost, but the larger size and higher charge density of calcium ions relative to lithium impairs diffusion kinetics and cyclic stability. In this work, an aqueous calcium–ion battery is demonstrated using orthorhombic, trigonal, and tetragonal polymorphs of molybdenum vanadium oxide (MoVO) as a host for calcium ions. Orthorhombic and trigonal MoVOs outperform the tetragonal structure because large hexagonal and heptagonal tunnels are ubiquitous in such crystals, providing facile pathways for calcium–ion diffusion. For trigonal MoVO, a specific capacity of ∼203 mAh g
−1
was obtained at 0.2C and at a 100 times faster rate of 20C, an ∼60 mAh g
−1
capacity was achieved. The open-tunnel trigonal and orthorhombic polymorphs also promoted cyclic stability and reversibility. A review of the literature indicates that MoVO provides one of the best performances reported to date for the storage of calcium ions.
Approaches to the discourse of terror
Authors: Patterson Katie J. , Pace-Sigge Michael T. L.
Published: July 2022

This chapter presents an investigation into the evidence of fixed language use within jihadist magazines and the extent to which these fixed patterns reflect specific power relations within the text community. The research presents the hypothesis that the writers of articles in jihadist magazines have become primed to employ the words and sets of words through their repeat usage (cf. Hoey 2005, 2017). Thus, lexical and grammatical associations and constructions are analysed to determine the extent to which language use is unique in our corpus. Evidence is presented in the unique way power relationships are linguistically expressed; it is argued here that this reflects the ways in which the writers are primed for their motives or aims of recruitment. Here, a number of words, which are fairly common in news discourse and are in the sematic field of power relations, have been identified as keywords in jihadist magazines. These show the collocation and colligation divergence where they are compared with occurrences in the COCA magazines sub-corpus covering the same time period.
Urban environments favorable to radical narratives
Authors: Moyano Manuel , Bélanger Jocelyn J. , Lobato Roberto M. , Trujillo Humberto M.
Published: July 2022

This paper aims to study the process of violent radicalization in El Puche, a marginal neighborhood of Spain with
a high percentage of disenfranchised Muslims. Particularly, we explore whether this neighborhood exhibits the factors proposed by
the 3N model of radicalization: needs, networks, and narratives. We present two studies in which we analyze these factors. In the
first study, we compare needs and networks between Muslims (N = 47) and Christians (N = 45). In
the second study, we analyze the interrelation of these factors in a sample of Muslims (N = 111). We found that people’s association with radical networks mediates the relationship between the quest for significance and radical narratives. We conclude that need,
network, and narrative are interconnected, and illustrate some of the dynamics that foster social exclusion and radicalization,
leading to supporting violence in this type of urban environments.
From image to function
Authors: García-Marín Javier , Luengo Óscar G.
Published: July 2022

The strategy of jihadist groups is based on objectives that are sometimes global. Specifically, many of these groups argue that Muslims, wherever they live, should fight for the establishment of an Islamic state or, at least, for such a state to be possible elsewhere. Therefore, taking advantage of the emergence of the Internet, they initiated an equally universal narrative strategy, with the production of a great deal of content, especially audiovisual texts. The effects of this material are known and, unfortunately, may be behind the terrorist actions of various individuals in many countries. Hence the concern of academics lies with their analyses and with the development of methodologies that can successfully deal with large amounts of multimodal information. The present research, therefore, aims to apply a quantitative procedure to the analysis of jihadist propaganda. Specifically, the authors have analysed 2,211 videos belonging to different terrorist groups, by applying an image classification algorithm. The results show that this type of approach has realistic possibilities of providing relevant information about this corpus – when realized, they may help to create automated analytical tools capable of dealing with the enormous amount of information that can be disseminated on-line.
A phase-field approach for detecting cavities via a Kohn–Vogelius type functional
Authors: Aspri Andrea
Published: July 2022

We deal with the geometrical inverse problem of the shape reconstruction of cavities in a bounded linear isotropic medium by means of boundary data. The problem is addressed from the point of view of optimal control: the goal is to minimize in the class of Lipschitz domains a Kohn–Vogelius type functional with a perimeter regularization term which penalizes the perimeter of the cavity to be reconstructed. To solve numerically the optimization problem, we use a phase-field approach, approximating the perimeter functional with a Modica–Mortola relaxation and modeling the cavity as an inclusion with a very small elastic tensor. We provide a detailed analysis showing the robustness of the algorithm through some numerical experiments.
Rapid assessment of REBCO CC angular critical current density J
c(B, T = 4.2 K, θ) using torque magnetometry up to at least 30 tesla
Authors: Jaroszynski J , Constantinescu A-M , Miller G , Xu A , Francis A , Murphy T , Larbalestier D C
Published: July 2022

Detailed design of REBa2Cu3O

7
−
x

(REBCO)-based magnets ideally relies on knowledge of the full angular and wide temperature range characterization of the critical current

I

c

of the REBCO coated conductors (CC) at high magnetic fields. In practice, however, obtaining

I

c

(
B
,
T
,
θ
)

data by the commonly used electrical transport technique is expensive, tedious, and difficult, due to high critical current values that exceed 2000 A for

B

|

|

a
b

-plane (θ = 90 deg). The conductors are often damaged during angular transport measurements at angles approaching the ab-plane. Therefore, so far, REBCO magnets have been designed without full

I

c

(
B
,
T
,
θ
)

data sets. Here, we present

J

c

(
B
,
T
,
θ
)

results for more than twenty samples of CC all made to the same advanced pinning specification produced by SuperPower Inc. For this, we employed torque magnetometry, benchmarking the results to transport

I

c

measurements mostly made away from ab-plane, finding good agreement with scaling factors ≈1–1.3. What is striking is the huge variety of properties exhibited by the samples, even for CC made recently. Given the huge attention now being paid to the effects of screening currents and to the torques generated by offsets between the tape plane and the local magnetic field vector, our data set suggests some caution in detailed design of such magnets without having data of the type presented here.
Pressure effects on the opto-electronic and mechanical properties of the double perovskite Cs2AgInCl6
Authors: Sholagberu A A , Yahya W A , Adewale A A
Published: July 2022

The double perovskite Cs2AgInCl6 is a potential material for the absorbing layer of a thin film solar cell due to its direct band gap. The only current limitation the material has is its wide band gap. A careful engineering of its structural, mechanical and opto-electronic properties with the aid of hydrostatic pressure ranging from 0 GPa16 GPa has been studied using density functional theory. The calculations were carried out using GGA-PBEsol (Perdew–Burke–Ernzerhof revised for solids) exchange correlation functional. It is found that the lattice constant reduces as the pressure increases, while the bulk modulus increases as the exerted pressure increases. The bulk moduli calculated from the elastic constants are found to be in agreement with those obtained via Birch-Murnaghan equation of state. This indicates the accuracy of the calculations, and it is achieved at all pressure values. The mechanical properties of the material are investigated, and the material is found to be anisotropic and ductile at all pressure considered. Due to the underestimation of the energy band gap by GGA-PBEsol exchange correlation functional, Tran-Blaha modified Burke Johnson (TB-mBJ), a metaGGA functional, was used to calculate the electronic and optical properties. The energy band gap is found to reduce from 2.746 eV at ambient pressure to 2.482 eV at 6 GPa and momentarily increases until it reached 2.501 eV at 16 GPa. The optical properties of Cs2AgInCl6 revealed its absorption threshold is in the visible range, although a shift in the absorption threshold is observed as pressure is applied on it. An 8.7 % increase in the refractive index is observed as pressure increases. The calculated absorption coefficient corresponds reasonably with the calculated band gap. The electron energy loss function and reflectivity of the material have also been investigated.
Improving parameter estimation precision by parity-time symmetric operation
Authors: Chen Fei , He Zhi , Wang Qiong
Published: July 2022

The enhancement of the precision of phase estimation in quantum metrology is investigated by employing parity-time (

P
T

) symmetric operation. We derive the exact expressions of the quantum Fisher information (QFI) and the success probability of the phase estimation for an exactly solving model consisting of a qubit interacting with a structured reservoir. Special attention is paid to the two schemes, i.e. pre-and post-

P
T

symmetric operations. We show that the QFI can be obviously enhanced by means of the

P
T

symmetric operation in different regimes. In addition, we also show that the magnitude of the decoherence involved in the

P
T

symmetric operation can be a general complex number, which extends the applicable scope of the

P
T

symmetric operation approach.
Nuclear liquid-gas phase transition within a Brueckner-Hartree-Fock approach*
Authors: Zhang Jing , Liu Hong-Ming , Li Zeng-Hua , Burgio G. F. , Schulze H.-J.
Published: July 2022

The critical parameters of the liquid-gas phase transition of symmetric nuclear matter are computed using the Brueckner-Hartree-Fock method at finite temperature by employing different realistic nucleon-nucleon potentials. Temperature effects on single-particle potentials, defect functions, and three-body forces are discussed in detail. Results obtained from the full procedure and frozen-correlations approximation are compared. We find critical temperatures of approximately 14 to 19 MeV and critical densities in the range of

to

, depending on the interactions employed.
Dibaryon resonances and short-range NN interaction*
Authors: Kukulin V.I. , Pomerantsev V.N. , Rubtsova O.A. , Platonova M.N. , Obukhovsky I.T.
Published: July 2022

The dibaryon concept for nuclear force is presented, assuming that the attraction between nucleons at medium distances is mainly due to the s-channel exchange of an intermediate six-quark (dibaryon) state. To construct the respective NN interaction model, a microscopic six-quark description of the NN system is used, in which symmetry aspects play a special role. It is shown that the NN interaction in all important partial waves can be described by the superposition of long-range t-channel one-pion exchange and s-channel exchange by an intermediate dibaryon. The model developed in this study provides a good description of both elastic phase shifts and inelasticities of NN scattering in all S, P, D, and F partial waves at energies from zero to 600–800 MeV and even higher. The parameters of the intermediate six-quark states, corresponding to the best fit of NN scattering data, are found to be consistent with the parameters of the known dibaryon resonances in those NN partial configurations, where their existence has been experimentally confirmed. Predictions for new dibaryon states are given as well.
Supergranular Fractal Dimension and Solar Rotation
Authors: Sowmya G. M. , Rajani G. , Paniveni U. , Srikanth R.
Published: July 2022

We present findings from an analysis of the fractal dimension of solar supergranulation as a function of latitude, supergranular cell size and solar rotation, employing spectroheliographic data in the Ca ii K line of solar cycle no. 23. We find that the fractal dimension tends to decrease from about 1.37 at the equator to about 1 at 20° latitude in either hemisphere, suggesting that solar rotation rate has the effect of augmenting the irregularity of supergranular boundaries. Considering that supergranular cell size is directly correlated with fractal dimension, we conclude that the mechanism behind our observation is that solar rotation influences the cell outflow strength, and thereby cell size, with the latitude dependence of the supergranular fractal dimension being a consequence thereof.
Trending IC design directions in 2022
Authors: Chan Chi-Hang , Cheng Lin , Deng Wei , Feng Peng , Geng Li , Huang Mo , Jia Haikun , Jie Lu , Lei Ka-Meng , Liu Xihao , Liu Xun , Liu Yongpan , Lu Yan , Nie Kaiming , Pan Dongfang , Qi Nan , Sin Sai-Weng , Sun Nan , Sun Wenyu , Xu Jiangtao , Yue Jinshan , Zhang Milin , Zhang Zhao
Published: July 2022

For the non-stop demands for a better and smarter society, the number of electronic devices keeps increasing exponentially; and the computation power, communication data rate, smart sensing capability and intelligence are always not enough. Hardware supports software, while the integrated circuit (IC) is the core of hardware. In this long review paper, we summarize and discuss recent trending IC design directions and challenges, and try to give the readers big/cool pictures on each selected small/hot topics. We divide the trends into the following six categories, namely, 1) machine learning and artificial intelligence (AI) chips, 2) communication ICs, 3) data converters, 4) power converters, 5) imagers and range sensors, 6) emerging directions. Hope you find this paper useful for your future research and works.
A 26-Gb/s CMOS optical receiver with a reference-less CDR in 65-nm CMOS
Authors: Pan Quan , Luo Xiongshi , Li Zhenghao , Jia Zhengzhe , Chen Fuzhan , Ding Xuewei , Yue C. Patrick
Published: July 2022

This paper presents a 26-Gb/s CMOS optical receiver that is fabricated in 65-nm technology. It consists of a triple-inductive transimpedance amplifier (TIA), direct current (DC) offset cancellation circuits, 3-stage gm-TIA variable-gain amplifiers (VGA), and a reference-less clock and data recovery (CDR) circuit with built-in equalization technique. The TIA/VGA front-end measurement results demonstrate 72-dBΩ transimpedance gain, 20.4-GHz −3-dB bandwidth, and 12-dB DC gain tuning range. The measurements of the VGA’s resistive networks also demonstrate its efficient capability of overcoming the voltage and temperature variations. The CDR adopts a full-rate topology with 12-dB imbedded equalization tuning range. Optical measurements of this chipset achieve a 10−12 BER at 26 Gb/s for a 215−1 PRBS input with a −7.3-dBm input sensitivity. The measurement results with a 10-dB @ 13 GHz attenuator also demonstrate the effectiveness of the gain tuning capability and the built-in equalization. The entire system consumes 140 mW from a 1/1.2-V supply.
The Effect of Extract Tannins from Spent Coffee Ground on Waste Water Treatment
Authors: Zulhipri
Published: July 2022

Green extraction processes to obtain high value bioactive compounds from raw natural materials and wastes has gained attention the past few years. In the present study, we investigated a Natural Deep Eutectic Solvent derived from two natural products, namely choline chloride and glucose as a potential solvent for the extraction of tannin compounds from spent coffee ground(SCG). A tannin was used as coagulant with the Poly aluminium chloride(PAC) as flocculant. Initially, jar test experiments were conducted with a varying dosage of coagulant and initial pH. Next, tests were carried out with different values of PAC dosage, flocculation time as well as sedimentation time to find out the optimum condition for colour removal. The supernatant layer of treated leachate from each test was analysed for colour, pH and conductivity. At optimum leachate pH of 5, experiments with 3 minutes flocculation time and sedimentation time of 10 minutes resulted in the highest colour removal (81.8%) at coagulant dosage of 100 mg/L, with 1 mg/L PAC being added. Coagulation flocculation system of as tannin-based coagulant with PAC as flocculant showed the promising result in decolourisation of wastewater.
Characterization and Identification of Magnetic Mineral Content in Industrial Dry Ink (Toner)
Authors: Helmita  , Rifai Hamdi , Dwiridal Letmi
Published: July 2022

Dry ink (toner) is a very promising industry. With an increase in sales based on a survey as much as 42% every years. This figure is predicted to continue to increase along with the development of printing technology using toner and the possibility to make a new formula from toner. The formula for the toner maker consists of a polymer, a colorant and a control agent. Control agents are generally used to activate the magnetic characteristics of toner the material contains is a magnetic mineral. In this study, characterization was carried out to identify magnetic minerals used as control agents for activating magnetic characteristics such as amount, composition, phase of magnetic minerals. The toner used is TN2356, SM, P115, P1102, H85, CP1028. With the susceptibility method using the Bartington Magnetic Susceptibility MS2B tool, the susceptibility values of each TN2356 (9,50 x 10−8 m3/kg) SM (514,03 x 10−8 m3/kg) P115 (46,17 x 10−8 m3/kg) CP1028 (566,80 x 10−8 m3/kg) H85 (21153,47 x 10−8 m3/kg) P1102 (21194,77 x 10−8 m3/kg). Composition of toner using X-Ray Fluorescence (Fe,Ti,Ce,Si,P). The phase used by X-Ray Diffraction is magnetite (Fe3O4),except 2 samples contain magnetic minerals but dominantly contain Cerium Oxide (CeO2) phase P115 and TN2356.
Identification of Rock Types from Iron Sand at Pasia Jambak Beach, Padang, West Sumatra
Authors: Visgun Dwi Anisa , Rifai Hamdi , Rahmayuni Riza , Yuwanda Ardilla Nofri , Rahmi Anisa , Dwiridal Letmi
Published: July 2022

West Sumatera is a region that has an abundance of natural resources in the form of iron sand, one of which is in the area of Pasia Jambak Beach, Padang. Pasia Jambak Beach is one type of beach in rumps and sandy beaches, which has grayish-brown sand and rough grains on its surface. Iron sand could be formed due to weathering of rocks and materials found around the coast, such as old ships and others. This study aims to see the type rock of origin and the composition of the magnetic mineral elements found in the iron sand of Pasia Jambak Beach. The composition of iron sand-forming elements can be seen using XRF. The analysis results using XRF showed that the most dominant element in the samples was Si (Silica) and Fe (Ferrum). Based on the SiO2
vs K2O diagram, it can be seen that the iron sand in the Pasia jambak Beach area comes from weathering of Basalt, Dacite, and Latite rocks. So, it could be concluded that the original rock group from iron sand at Pasia Jambak Beach is the Calc-Alkaline group (medium Potassium content) and High K Calc-Alkaline (high Potassium content).
The Effect of Acid, Salt and Base Immersion on Hydrophobic Properties of SiMn/PS Nanocomposite
Authors: Ratnawulan R , Putri Suchi R , Septiana Dian , Putri Sisi Gusti , Fauzi A
Published: July 2022

The manufacture of hydrophobic coatings that have self-cleaning properties has become a research trend now, but when applied, the coating is still easily damaged due to contact with other objects and is not durable due to corrosion. This problem will certainly hinder the application of hydrophobic surfaces in industry. For this reason, the researchers mixed substrates that had anti-corrosion properties such as silica and hard and strong properties such as manganese to be able to solve the previous problem, and the method used is spin coating. The precursors were made by adding 0.5 grams of polystyrene, 0.2 grams of silica nanoparticles and 0.2 grams of manganese nanoparticles. The coating was done by using the spin coating method and the calcination temperature was 60°C using an oven for 1 hour. The research results indicate that during immersion in an acid solution (pH 6), a salt solution (pH 7) and an alkaline solution (pH 11) as well as before immersion, there is a decrease in crystal size. For the best contact angle results obtained after immersion in acid is 97.28° with salt and base is 91.65° and 95.21° and before immersion is 104.70°.
Automatic Transfer Switch Solar Cell Inverter System Based on Android Application
Authors: Audia Washilla , Mairizwan  , Anshari Rio , Yulkifli
Published: July 2022

The main electricity supply is PLN, which is not always continuous in its distribution, one day there will be blackouts caused by disturbances in the transmission or distribution system and the limited availability of fossil energy. This can result in disruption of human activities and productivity. The solution to this problem is to develop an Automatic Transfer Switch on a hybrid system that utilizes Android-based solar cell and PLN energy. This system will work automatically as a hybrid power plant by utilizing ATS as well as remote monitoring and control. This research is classified as laboratory experimental engineering research. The data collection technique was carried out by direct measurement by varying the electrical power needed by the house. This research was developed using an application with simulation results when the harvesting conditions of the solar panels are the same as the power required by the house, the system will automatically supply power from full solar cells to the house. When harvesting conditions from solar panels are minimal, the system will automatically supply electricity from solar cells and PLN to the house. So the appliance can run as expected and the power savings at home when using this system is 84%.
Irregular Magnetic Susceptibility Pattern of Iron Sand from Pasia Jambak Beach, Pasia Nan Tigo, Padang, Indonesia
Authors: Rahmi Anisa , Rifai Hamdi , Rahmayuni Riza , Yuwanda Ardilla Nofri , Visgun Dwi Anisa , Dwiridal Letmi
Published: July 2022

West Sumatra has the potential of abundant natural resources in the form of iron sand, one of which is located in the Pasia Jambak Beach area, Pasia Nan Tigo, Padang. Basically iron sands have magnetite (Fe3O
4), hematite (α-Fe2O
3), and maghemite (γ-Fe2O
3) which can be used as a mineral of high economic value. However, the iron sand of Pasia Jambak Beach, Pasia Nan Tigo, has no known magnetic mineral. This study aims to investigate the magnetic mineral content of the iron sand of Pasia Jambak Beach, Pasia Nan Tigo, Padang based on its magnetic susceptibility. The variation of the investigated susceptibility value is based on depth. Magnetic susceptibility measurements were carried out using a Bartington Magnetic Susceptibility Meter with a MS2B sensor dual frequency. The results showed that the magnetic susceptibility value of the iron sand of Pasia Jambak Beach, Pasia Nan Tigo, Padang varied based on the depth from 291.1 x 10−8 m3/kg to 12445.5 x 10−8 m3/kg with an average value of 2016.35 x 10−8 m3/kg. Variations in the susceptibility value of iron sand obtained at each depth have changes or variations in the susceptibility value that are irregular or do not have a certain pattern.
PyTherNal: A python program for analyzing curie temperature from thermomagnetic data
Authors: Nanlohy George Billy , Yosia Gabrian Granito , Salim Christopher , Mariyanto Mariyanto
Published: July 2022

Thermomagnetic analysis is performed by bringing subject materials into its cooled and heated state, followed by analyzing the magnetic moment change. Performing these would result in obtaining the Curie Temperature of the materials, which is essential in estimating magnetic minerals contained in material samples. PyTherNal (Python Thermomagnetic Analyzer) is a thermomagnetic analysis tool in Python environment meant to assist in analyzing thermomagnetic data. The advantages of Python in its functionality and flexibility of being used in any operating system (OS) became the main reason for the program to be written in Python. PyTherNal is designed to assist in estimating Curie temperature of materials through thermomagnetic method, by locating the maximum curvature of the highest value of second (2nd) derivative of both cooling and heating data. To facilitate these, PyTherNal generates three figures, which are the curves for the thermomagnetic data, its 1stderivative, and its 2ndderivative. An advantage of the program is that it performs smoothing to increase the accuracy in estimating the Curie temperature as doing so would significantly minimize the variability of the derivative curve. Since the program is written in Python, it is open-source and therefore free to use. It is also capable of cross-platforming.
Characteristic and Photostability of Astaxanthin Extract from Shrimp Shells by Microwave Assisted Extraction Using Nades Solvent
Authors: Nanda Elsa Vera , Erdawati  , Pratiwi Yussi , Putri Eriska Rahmi
Published: July 2022

This study aims to determine the effect of temperature and light UV on the colour photostability of astaxanthin microcapsule. Astaxanthin from shrimp shells, extracts by microwave assisted extraction using NADES as the solvent. The optimal conditions obtained were, a microwave power of 180 W, an extraction time of 5 minutes, and ratio NADES shrimp shell powder 8: 1 mL/g with yield astaxanthin of 7,466 ppm. Astaxanthin is purified using petroleum ether and dehydrated with anhydrous natrium sulphite. The purification results showed an increase in the brightness of the astaxanthin colour, expressed in L * 48.70 and an h value of 73.12. In order to maintain their photostability colour, astaxanthin is encapsulated with nano chitosan. The astaxanthin microcapsules were characterized by SEM, EDX, FTIR, and XRD, for chemical structure, morphological, and crystallization observation. It was reported that a photostability astaxanthin microcapsule was slightly enhanced. The test results showed that the colour of the astaxanthin microcapsules did not change after 30 minutes of UV exposure. The heat resistance test also shows that at 200° C the colour of astaxanthin microcapsule turns brown due to the solvent and the water in the astaxanthin microcapsule evaporates.
The Development and Usability of Optics Kit as a Teaching Aid among Physics Trainee Teachers
Authors: Kadir Nor Sahkkina , Yaacob Mohd Ikhwan Hadi
Published: July 2022

This study was conducted to develop a teaching aid known as the Optics Kit. This Optics Kit consists of tools and learning modules that were designed according to form four physics DSKP syllabus. The study utilized the ADDIE Model as instructional design which embraced the quantitative survey method. The developed Optics Kit has obtained validity from the experts while its usability were conducted among physics trainee teachers which consists of 30 trainee teacher from the Bachelor of Education (Physics) programme that were selected via cluster sampling method. The instruments used in this study was the validity questionnaire and usability test which were adapted from previous research. Data analysis was conducted using SPSS software. Results obtained from this study found that the validity value of Optics Kit and the usability test based on the percentage of expert consent are 100% and 97.9%, while the mean score value for the usability of this Optics Kit is 4.98. These findings show that the Optics Kit has high validity and strong agreement on usability of the Optics Kit as a teaching aid. In conclusion, this Optics Kit was successfully developed to be used as a teaching aid for the topic of Light and Optics.
Development and Usability of ‘Gravigame’ in Kepler’s Law Among Physics Trainee Teacher
Authors: Ismail Farah Najwa binti , Mohtar Lilia Ellany binti , Al-Zuhairi Omar Ayad Fadhil
Published: July 2022

This study aimed to develop a ‘Gravigame’ in Kepler’s law and to evaluate its usability among physics trainee teachers at one of the public universities in Malaysia. This study uses a developmental research design by applying the ADDIE model. The research sample consisted of 30 trainee physics teachers who were randomly selected from seven and eight semesters’ students. Two research instruments were used, namely the expert validation form and usability questionnaire adapted from the USE Questionnaire. Data from the usability questionnaire were analysed descriptively using mean and standard deviation (s.d). Data showed that the developed game has a high validity with 94% of expert agreement. The usability data analyses showed that the ‘Gravigame’ has an overall of mean score 3.81 (s.d = 0.282). The three constructs that represent usability namely usefulness, ease of use and satisfaction are at a good level with the mean score of 3.80, 3.76 and 3.86 respectively. In conclusion, the research has successfully developed a validated ‘Gravigame’ that can be used as a teaching aid. For implication, the ‘Gravigame’ game is suitable for classroom learning, making it easier for teachers to assess students and helping students understand the subtopic of Kepler’s law.
The Analysis of Suitability Level High School Physics Materials with Covid-19 Knowledge for the Development of Research-Based Physics E-Books
Authors: Nurhaliza Putri , Fauzi Ahmad
Published: July 2022

Padang is a city affected by Covid-19 with a high threat. One of the efforts to break the chain the spread Covid-19 is by incorporating knowledge of Covid-19 in learning Physics. However, until now how the level of compatibility physics material with knowledge of Covid-19 is not known. This type of research is descriptive research with qualitative approach. The population is all high school physics material and taking samples of high school physics material for 3 consecutive semesters based on the 2013 curriculum. The research procedure includes: 1) preparation stage, 2) implementation stage, 3) completion stage. In the physics e-book for class X first semester basic competencies 3.1 is included in the appropriate category, for 3.2 and 3.4 is in the quite appropriate category, for 3.3, 3.5 and 3.6 is in the inappropriate category. For second semester basic competencies 3.7, 3.8 and 3.11 fall into category not enough in accordance, for 3.9 enter the appropriate category and 3.10 fall into the category quite appropriate. For class XI first semester basic competencies 3.1 and 3.2 fall into category no in accordance, for 3.3, 3.4 and 3.5 are in the quite appropriate category and 3.6 fall into category not enoughin accordance.
Practicality of Basic Electronics Module Integrating Creative Thinking in Diode Circuit Material and Its Application
Authors: Hufri  , Triani Frima
Published: July 2022

The existing learning modules can develop students’ understanding of material skills, but they are still general in nature and have not integrated creative thinking in them. This study ambitions to determine the practicality of fundamental electronics modules that integrate creative thinking abilities in diode circuit subject matter and their applications. The studies carried out is a kind of Research and Development, specifically the development of fundamental electronics modules that integrate creative thinking skills in diode circuit materials and their applications. The data collection instruments used were validation sheets and practicality test sheets by the lecturer. The product and data analysis techniques used were product validity analysis and product practicality analysis. The practicality value of the module by basic electronics lecturers with an average value of 91.5%. Based on this value, So this shows that the basic electronics module that was developed to integrate creative thinking abilities in the discussion of diode circuits and its application already has a very practical category.
Development of Edmodo-Based Online Learning Media Devices Based on Modified Free Inquiry (MFI) on Electric Circuit Materials For Distance Learning (PJJ)
Authors: Susanti Dwi , Serevina Vina , Rahma K A , Mandagi A F
Published: July 2022

Edmodo can help teachers build virtual classes according to classroom learning conditions based on real class divisions at school, which contain discussions, quizzes, and assignments at the end of each lesson. By applying the model to Modified Free Inquiry (MFI) Edmodo online learning media, interactions, and communication in the classroom can be shaped like conventional classrooms. The purpose of this study was to develop online learning media tools assisted by the Edmodo application in the physics material of electric circuits with the learning model MFI. The research method used is Research and Development (RnD) with the development process using the 4D model, consisting of define, design, develop, and disseminate. The data collection instrument involved 2 material validators, 2 media validators, and 2 learning validators and the teacher’s response was tested. This study shows that the validation results and teacher responses are obtained with an average percentage of the assessment of 83%. Based on the results of research and discussion can be concluded that online learning media device based Edmodo assisted MFIs are categorized as valid and feasible to use
Learning Application Design Using Physicatz of Geography and Science Edition: Solar System for High School
Authors: Fahdiran Riser , Serevina V , Yaqiin M H , Tahara A R
Published: July 2022

A brand-new comprehensive education application by Physicatz in the edition of the science of solar system has been developed and tested in a teaching-learning activity in State High School 30 Jakarta on 09 April 2020. The purpose of this research is to know the eligibility of using this comprehensive application for instructional activity as a learning media for this subject. This application’s features consist of a magnificent 3D solar system reading material, an interactive quiz, exercises, and a video-based comic that will take us to explore the solar system. The method used in this research was ADDIE Instructional Design (ID) methods with steps: (1) Analysis, (2) Design, (3) Develop, (4) Implement, (5) Evaluate. This research was tested on 100 students of 10th grade State High School 30 Jakarta. This application has been tested through validity examination and received an average percentage of 83,44% from the professional subject matter, 92,31% from the professional learning resources, and 91,97% from the subject matter teacher. The students also took part in the test of using this application to learning Earth and Space Science: the solar system, and received an average percentage of 91,99%.