bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective Role of Activated Protein C against Viral Mimetic Poly(I:C)-Induced Inflammation
Authors: Cai Xiaofeng , Panicker Sumith R. , Biswas Indranil , Giri Hemant , Rezaie Alireza R.
Published: March 2021

Activated protein C (APC) is an anticoagulant plasma serine protease which exhibits potent cytoprotective and anti-inflammatory activities. Here, we studied protective effects of APC on the proinflammatory function of polyinosinic:polycytidylic acid [poly(I:C)], a synthetic analog of viral double-stranded RNA, in cellular and animal models. Poly(I:C) induced histone H3 extranuclear translocation via interaction with toll-like receptor 3 in two established endothelial cell lines. Furthermore, poly(I:C) induced histone H3 extranuclear translocation in J774A.1 macrophages and human neutrophils and formation of macrophage and neutrophil extracellular traps (ETs). Mechanistically, poly(I:C) was found to upregulate expression of peptidylarginine deiminase 4 and enhance its interaction with histone H3, thereby leading to increased histone citrullination and neutrophil ET formation. Poly(I:C) elicited proinflammatory signaling responses by inducing nuclear factor kappa B activation and disrupting endothelial cell permeability. In vivo, poly(I:C) enhanced cell surface expression of Mac-1 on neutrophils in mice and facilitated their infiltration to lung tissues. Poly(I:C) also downregulated thrombomodulin expression in mouse tissues and reduced its circulating soluble level in plasma. We demonstrate in this study that APC and a signaling-selective mutant of APC effectively inhibit proinflammatory signaling effects of poly(I:C) in both cellular and animal models. We further demonstrate that unlike the requirement for endothelial protein C receptor on endothelial cells, the integrin Mac-1 is involved in the protease-activated receptor 1-dependent APC inhibition of macrophage ET formation in J774A.1 cells. Taken together, these results support a key role for APC signaling in inhibiting the viral mimetic-induced proinflammatory signaling responses and histone translocation-associated formation of ETs by innate immune cells.
Characterization of free particle dynamics in an idealized pilot-wave system
Authors: Kim Meeri
Published: March 2021

A theoretical framework for evolving pilot-wave systems revealed new orbital states for the free particle, such as wobbling and precessing spin states.
Noise tolerance of photonic entanglement can be significantly enhanced
Authors: Bandari Anashe
Published: March 2021

Researchers show how the dimensionality of photonic systems can be exploited to outperform qubits in terms of noise tolerance.
Electronic bandgap miniaturized UWB antenna for near-field microwave investigation of skin
Authors: Alani Sameer , Zakaria Zahriladha , Saeidi Tale , Ahmad Asmala , Alsariera Hussein , Al-Heety Othman S. , Mahmood Sarmad Nozad
Published: March 2021

Near-field microwave investigation and tomography has many practical applications, especially where the trend of fields and signals in different environments is vital. This article shows an elliptical patch ultra-wideband antenna fed by a transmission line for the near-field characterization of cancerous cells in the skin. The antenna comprises an elliptical patch, stub loading to shift the band to lower bands, and an electronic bandgap structure on the ground side. Even though the antenna has a low profile of 15 × 15 mm2, the proposed antenna has more promising results than recent studies. Furthermore, both simulated near-field and far-field results show a broad bandwidth of 3.9–30 GHz and a resonance at 2.4 GHz applicable for industrial, scientific, and medical band applications. The proposed antenna also illustrates a peak gain of 6.48 dBi and a peak directivity of 7.09 dBi. Free space and skin (on a layer of breast fat and a tumor with a diameter of 4 mm at the boundary of skin and breast) are used as test environments during the simulation and measurement of near-field and far-field investigations while considering a phantom breast shape. Both far-field and near-field microwave investigations are performed in Computer Simulation Technology studio, and results are then compared with the measured data. The simulated and measured results are in good agreement, and the focused energy around the tumor is completely reconstructed. Therefore, the proposed antenna can be an adequate candidate for the differentiation of breast skin and tumor to reconstruct the tumor’s image.
Adversarial reverse mapping of condensed-phase molecular structures: Chemical transferability
Authors: Stieffenhofer Marc , Bereau Tristan , Wand Michael
Published: March 2021

Switching between different levels of resolution is essential for multiscale modeling, but restoring details at higher resolution remains challenging. In our previous study, we have introduced deepBackmap, a deep neural-network-based approach to reverse-map equilibrated molecular structures for condensed-phase systems. Our method combines data-driven and physics-based aspects, leading to high-quality reconstructed structures. In this work, we expand the scope of our model and examine its chemical transferability. To this end, we train deepBackmap solely on homogeneous molecular liquids of small molecules and apply it to a more challenging polymer melt. We augment the generator’s objective with different force-field-based terms as a prior to regularize the results. The best performing physical prior depends on whether we train for a specific chemistry or transfer our model. Our local environment representation combined with the sequential reconstruction of fine-grained structures helps in reaching transferability of the learned correlations.
Charge-offset stability of single-electron devices based on single-layered Fe nanodot array
Authors: Gyakushi Takayuki , Asai Yuki , Honjo Shusaku , Tsurumaki-Fukuchi Atsushi , Arita Masashi , Takahashi Yasuo
Published: March 2021

In metal-based single-electron devices (SEDs), charge-offset drift has been observed, which is a time-dependent instability caused by charge noise. This instability is an issue in the application of new information processing devices, such as neural network devices, quantum computing devices (charge sensing), and reservoir computing devices. Therefore, the charge-offset drift in metal-based SEDs needs to be suppressed. However, the charge-offset stability of metal-based SEDs has not been investigated in depth, except in the case of Al and Al2O3 SEDs. In this work, Fe-based SEDs formed by single-layer Fe nanodot arrays embedded in MgF2 were studied with regard to their charge-offset stability. Using devices that produce simple current oscillations, the charge-offset drift (ΔQ0) of Fe-based SEDs was evaluated by focusing on peak shifts of the simple current oscillation over time, despite the use of a multi-dot system. This drift (ΔQ0 ≈ 0.3e) was shown to be much lower than in SEDs with Al-dots and Al2O3 tunnel junctions. Notably, the charge-offset drift in the metal-based SEDs was suppressed using the Fe–MgF2 system. The excellent stability of these devices was attributed to the material properties of the Fe–MgF2 system. Finally, as the Fe nanodot array contained numerous dots, the effect of satellite dots acting as traps on the charge-offset instability was discussed. The findings of this study will be important in future applications of metal-based SEDs in new information processing devices.
Effects of Fe doping on the visible light absorption and bandgap tuning of lead-free (CsSnCl3) and lead halide (CsPbCl3) perovskites for optoelectronic applications
Authors: Kholil M. I. , Bhuiyan M. T. H. , Rahman M. Atikur , Ali M. S. , Aftabuzzaman M.
Published: March 2021

The halide perovskite solar cells nowadays have emerged as a potential candidate for photovoltaic technology because of their high efficiency, low-cost, and facile fabrication process. In this study, the structural, elastic, electronic, and optical properties of pure and metal (Fe) doping lead-free perovskite CsSnCl3 and lead halide perovskite CsPbCl3 have been calculated by using density functional theory. The present study shows that the metal doping exhibits high absorption and high conductivity than the pure counterpart due to reducing the bandgap. The bandgap of Fe-doped CsSnCl3 is narrowing more than Fe-doped CsPbCl3. The Fe-doped CsSnCl3 reveals a more enhanced optical nature than the Fe-doped CsPbCl3 owing to the greater shipment of absorption peaks toward the lower energy region and the narrowing bandgap. The mechanical parameters show that the pure and Fe-doped samples are mechanically stable. The failure mode indicates that the Fe-doped perovskites are highly ductile in nature as pristine samples, which makes them suitable for use in thin films. The electronic band structure of doped samples exhibited the intermediate state (donor level) in the bandgap. The creation of intermediate states helps the excited photoelectron to easily transfer from the valence to the conduction band. A combined analysis of metal doping in lead halide and lead-free halide demonstrated that Fe-doped CsSnCl3 is more promising to use in solar cells and other optoelectronic applications.
High-speed wavefront determination method based on single in-and-out electric field analysis to focus light through highly scattering medium
Authors: Cao Jing , Yang Qiang , Miao Yusi , Li Yan , Wang Pinghe , Chen Zhongping
Published: March 2021

We develop a new type of high-speed wavefront determination method with single feedback measurement to focus light through a 15.2 scattering mean free path in ∼113 ms. Our method is based on a heterodyne-detection phase sensitivity interferometer. First, the matrix which describes the light propagation process in the sample is measured by single input and output optical fields’ analysis. Then, by using a spatial light modulator to reshape the incident light with a matched wavefront, a focused beam is observed behind the sample. The proposed high-speed light focusing method will open new spot scanning mode toward deeper imaging through highly scattering biological tissues.
Integration of thixotropy into Giesekus model for characterization of human blood
Authors: Armstrong Matthew , Pincot Andre
Published: March 2021

Recent work modeling the rheological behavior of human blood indicates that blood has all the hallmark features of a complex material, including shear-thinning, viscoelastic behavior, yield stress, and thixotropy. Using a recently developed linear superposition technique to account for the effects of thixotropy with the Giesekus model and recently collected human blood rheological data from a strain-controlled rheometer, we perform parametric and statistical analysis of the parameter values of 5 donors. The work is validated with the incorporation of a recent thixotropic framework to model elastic and viscoelastic contributions from the microstructure. The elastic and viscoelastic stress contributions from the microstructure are then linearly superimposed with the viscoelastic backbone solution for stress given by the classic Giesekus rheological model. Demonstrated here are a parametric and statistical analysis and a comparison of the ability of the new enhanced thixotropic Giesekus model to predict large amplitude oscillatory shear and uni-directional large amplitude oscillatory shear flow. In addition, there is a new methodology to model the normal forces of blood. We compare this approach to other recently developed enhanced thixotropic Oldroyd-8 inspired models.
Systematic review and meta-analysis of biosimilar for the treatment of rheumatoid arthritis informing the 2020 update of the Japan College of Rheumatology clinical practice guidelines for the management of rheumatoid arthritis
Authors: Tanaka Eiichi , Kawahito Yutaka , Kohno Masataka , Hirata Shintaro , Kishimoto Mitsumasa , Kaneko Yuko , Tamai Hiroya , Seto Yohei , Morinobu Akio , Sugihara Takahiko , Murashima Atsuko , Kojima Masayo , Mori Masaaki , Ito Hiromu , Kojima Toshihisa , Sobue Yasumori , Nishida Keiichiro , Matsushita Isao , Nakayama Takeo , Yamanaka Hisashi , Harigai Masayoshi
Published: March 2021

Objectives

To evaluate the efficacy and safety of biosimilars compared with reference biological disease modifying antirheumatic drugs (bDMARDs) in patients with rheumatoid arthritis (RA) as a part of the process of developing the 2020 update of the Japan College of Rheumatology guidelines for the management of RA.

Methods

PubMed, Cochrane Library, and Japan Centra Revuo Medicina were searched for articles to conduct a systematic review (SR). The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system.

Results

Twenty randomized controlled trials were included (biosimilars of infliximab, etanercept, and adalimumab). A meta-analysis revealed that the risk ratios (RRs) and 95% confidence intervals (CIs) of achieving the American College of Rheumatology 50% response (ACR50) at week 24 and serious adverse events (SAEs) for biosimilars compared with the reference bDMARDs were 1.04 (0.98–1.10) and 0.84 (0.61–1.18), respectively. The RRs of achieving ACR50 and SAEs at week 24 were respectively 0.93 (0.69–1.26) and 2.15 (0.55–8.35) in the patients who switched to biosimilars from the reference bDMARDs and 0.92 (0.76–1.12) and 1.41 (0.32–6.15) in those who continued the reference bDMARDs.

Conclusion

Biosimilars and reference bDMARDs were equally useful for the management of RA.
From the discovery of DNA to current tools for DNA editing
Authors: Maguin Pascal , Marraffini Luciano A.
Published: March 2021

In 1944, the Journal of Experimental Medicine published the groundbreaking discovery that DNA is the molecule holding genetic information (1944. J. Exp. Med.https://doi.org/10.1084/jem.79.2.137). This seminal finding was the genesis of molecular biology and the beginning of an incredible journey to understand, read, and manipulate the genetic code.
AIM2 controls microglial inflammation to prevent experimental autoimmune encephalomyelitis
Authors: Ma Chunmei , Li Sheng , Hu Yingchao , Ma Yan , Wu Yuqing , Wu Chunyan , Liu Xue , Wang Bingwei , Hu Gang , Zhou Jiawei , Yang Shuo
Published: March 2021

The role of the PYHIN family member absent in melanoma 2 (AIM2), another important inflammasome sensor, in EAE remains unclear. In this study, we found that AIM2 negatively regulates the pathogenesis of EAE independent of inflammasome activation. AIM2 deficiency enhanced microglia activation and infiltration of peripheral immune cells into the CNS, thereby promoting neuroinflammation and demyelination during EAE. Mechanistically, AIM2 negatively regulates the DNA-PK–AKT3 in microglia to control neuroinflammation synergistically induced by cGAS and DNA-PK. Administration of a DNA-PK inhibitor reduced the severity of the EAE. Collectively, these findings identify a new role for AIM2 in controlling the onset of EAE. Furthermore, delineation of the underlying inflammasome-independent mechanism highlights cGAS and DNA-PK signaling as potential targets for the treatment of heterogeneous MS.
The topological criticality in disordered non-Hermitian system
Authors: Bao Xi-Xi , Guo Gang-Feng , Du Xue-Peng , Gu Huai-Qiang , Tan Lei
Published: March 2021

Disorders have a rich influence on topological and localized properties. Here, we explore the effects of different type of disorders (intracell and intercell) on the non-Hermitian system. We first exhibit the phase diagram and find that the intracell disorder and intercell disorder can broaden and narrow the topological region, respectively. Moreover, the skin effect, which is unique in the non-Hermitian system, is broken by disorders. Furthermore, we propose the generalized localization length to settle the issue of how to determine the topological phase boundary explicitly in the disordered non-Hermitian system. Significantly, the rationality of this definition can be verified by similarity transformation, in which we prove that the topological invariant remains invariant. Finally, a byproduct of our definition is that one can analytically get the criticality of topology in the clean-limit non-Hermitian system.
An electrochemically actuated drug delivery device with in-situ dosage sensing
Authors: Yi Ying , Chiao Mu , Wang Bo
Published: March 2021

Very few conventional micro-electro-mechanical systems as drug delivery devices have in-situ dosage monitoring sensors, this thus brings inaccurate released dose, which results in either inefficient pharmaceutical effects or over-dose induced side effects. In this work, we integrate a low-cost piezoresistive sensor with an electrochemically actuated drug delivery device, and investigate its dosage monitoring performance. Different from the conventional sensor fabrication based on mixing conductive particles into liquid polymer, our proposed sensor is constructed from solidified carbon ink film embedded in a polydimethylsiloxane (PDMS) membrane, which can obtain an optimum tradeoff between the gauge factor and maximum achievable displacement. An electrolytic reaction induces the electrolysis-bubble in the actuator chamber with an increase in pressure, which causes displacement of the PDMS sealing membrane. This provides the actuation force to deliver the drug solution. The displacement of the PDMS membrane that determines the pumped volume of the drug solution is quantified through a resistance change of the embedded piezoresistive sensor. We report a single pumping volume of up to 7 μl, which is monitored by the resistance change ratio (ΔR/R), ranging from 2% to 12% with a dosage sensing accuracy of ±6.5%.
Study of the optical response and coherence of a quadratically coupled optomechanical system
Authors: Kundu Akash , Jin Chao , Peng Jia-Xin
Published: March 2021

In this article, we theoretically investigate a quadratically coupled optomechanical system with a two-level atom. At steady-state, we examine the variation of transmission intensity with various parameters of the system as well as investigate the transmission in lower/upper sidebands. Moreover, taking into account the quantum fluctuations, we extend our investigation towards the study of quantum coherence for the optomechanical system. The result shows that the coherence inside the proposed cavity can be efficiently controlled by varying atom-to-photon coupling and modified optical detuning. We also discuss and provide a physical explanation of why the atomic coherence can surpass the optical and mechanical ones.
Proca in the sky
Authors: Heisenberg Lavinia , Villarrubia-Rojo Hector
Published: March 2021

The standard model of cosmology, the ΛCDM model, describes the evolution of the
Universe since the Big Bang with just a few parameters, six in its basic form.
Despite being the simplest model, direct late-time measurements of the Hubble
constant compared with the early-universe measurements result in the so-called H0 tension.
It is claimed that a late time resolution is predestined to fail
when different cosmological probes are combined. In this work, we shake the ground
of this belief with a very simple model.
We show how, in the context of cubic vector Galileon models, the Hubble tension
can naturally be relieved using a combination of CMB, BAO and SNe observations without
using any prior on H0. The tension can be reduced even further by including the local
measurement of the Hubble constant.
Analytic formula for the dynamics around inflation end and implications on primordial gravitational waves
Authors: Ito Asuka , Soda Jiro , Yamaguchi Masahide
Published: March 2021

We argue that primordial gravitational waves have a spectral break and
its information is quite useful for exploring the early universe.
Indeed, such a spectral break can be a fingerprint of the end of
inflation, and the amplitude and the frequency at the break can tell us
the energy scale of inflation and the reheating temperature
simultaneously. In order to investigate the spectral break, we give an
analytic formula for evolution of the Hubble parameter around the end of
inflation where the slow roll approximation breaks down. We also
evaluate the spectrum of primordial gravitational waves around the
break point semi-analytically using the analytic formula for the
inflation dynamics.
Constraining the inflationary potential with spectral distortions
Authors: Schöneberg Nils , Lucca Matteo , Hooper Deanna C.
Published: March 2021

Measuring spectral distortions (SDs) of the cosmic microwave background (CMB) will provide new constraints on previously unexplored scales of the primordial power spectrum, allowing us to extend the probed parameter space by several orders of magnitude in k-space, which could have significant implications in the context of primordial black holes and gravitational waves, among others. Here we discuss how various models of inflation can be tightly constrained by the combination of current and future CMB SD and anisotropy experiments. In particular, we investigate the constraining power of SD experiments such as FIRAS, PIXIE, and PRISM in conjunction with CMB anisotropy probes such as Planck or CMB-S4 plus LiteBIRD. Building on the latest version of the Boltzmann solver class (v3.0), here we also consistently marginalize over the possible galactic and extra-galactic foregrounds for the SD missions. With this numerical setup, we are able to realistically forecast the improvements that the increased lever-arm provided by the addition of the various SD missions will bring for several combinations of the aforementioned experiments. As a result, in all considered models we observe that SDs provide a highly significant tightening of the constraints by up to 640%, and increase the figure of merit up to a factor of around 1600.
Offline Correction of Atmospheric Effects on Single-dish Radio Spectroscopy
Authors: Sawada Tsuyoshi , Chang Chin-Shin , Francke Harold , Gomez Laura , Mangum Jeffrey G. , Miyamoto Yusuke , Nakazato Takeshi , Nishie Suminori , Phillips Neil M. , Shimajiri Yoshito , Sugimoto Kanako
Published: March 2021

We present a method to mitigate the atmospheric effects (residual atmospheric lines) in single-dish radio spectroscopy caused by the elevation difference between the target and reference positions. The method is developed as a script using the Atmospheric Transmission at Microwaves (ATM) library built into the Common Astronomy Software Applications (CASA) package. We apply the method to the data taken with the Total Power Array of the Atacama Large Millimeter/submillimeter Array. The intensities of the residual atmospheric (mostly O3) lines are suppressed by, typically, an order of magnitude for the tested cases. The parameters for the ATM model can be optimized to minimize the residual line and, for a specific O3 line at 231.28 GHz, a seasonal dependence of a best-fitting model parameter is demonstrated. The method will be provided as a task within the CASA package in the near future. The atmospheric removal method we developed can be used by any radio/millimeter/submillimeter observatory to improve the quality of its spectroscopic measurements.
Cathodic shift of onset potential on TiO2 nanorod arrays with significantly enhanced visible light photoactivity via nitrogen/cobalt co-implantation*
Authors: Song Xianyin , Zhou Hongtao , Jiang Changzhong
Published: March 2021

Despite anionic doping has been widely implemented to increase the visible light activity of TiO2, it often gives rise to a dramatical anodic shift in current onset potential. Herein, we show an effective method to achieve the huge cathodic shift of TiO2 photoanode with significantly enhanced visible light photo-electrochemical activity by nitrogen/cobalt co-implantation. The nitrogen/cobalt co-doped TiO2 nanorod arrays (N/Co-TiO2) exhibit a cathodic shift of 350 mV in onset potential relative to only nitrogen-doped TiO2 (N-TiO2). Moreover, the visible-light (λ > 420 nm) photocurrent density of N/Co-TiO2 reaches 0.46 mA/cm2, far exceeding 0.07 mA/cm2 in N-TiO2 at 1.23 V versus reversible hydrogen electrode (RHE). Systematic characterization studies demonstrate that the enhanced photo-electrochemical performance can be attributed to the surface synergic sputtering of high-energy nitrogen/cobalt ions.
Real time high accuracy phase contrast imaging with parallel acquisition speckle tracking*
Authors: Hu Zhe , Hua Wen-Qiang , Wang Jie
Published: March 2021

X-ray speckle tracking based methods can provide results with best reported angular accuracy up to 2 nrad. However, duo to the multi-frame requirement for phase retrieval and the possible instability of the x-ray beam, mechanical and background vibration, the actual accuracy will inevitably be degraded by these time-dependent fluctuations. Therefore, not only spatial position, but also temporal features of the speckle patterns need to be considered in order to maintain the superiority of the speckle-based methods. In this paper, we propose a parallel acquisition method with advantages of real time and high accuracy, which has potential applicability to dynamic samples imaging as well as on-line beam monitoring. Through simulations, we demonstrate that the proposed method can reduce the phase error caused by the fluctuations to 1% at most compared with current speckle tracking methods. Meanwhile, it can keep the accuracy deterioration within 0.03 nrad, making the high theoretical accuracy a reality. Also, we find that waveforms of the incident beam have a little impact on the phase retrieved and will not influence the actual accuracy, which relaxes the requirements for speckle-based experiments.
Interaction induced non-reciprocal three-level quantum transport*
Authors: Li Sai , Chen Tao , Liu Jia , Xue Zheng-Yuan
Published: March 2021

Besides its fundamental importance, non-reciprocity has also found many potential applications in quantum technology. Recently, many quantum systems have been proposed to realize non-reciprocity, but stable non-reciprocal process is still experimentally difficult in general, due to the needed cyclical interactions in artificial systems or operational difficulties in solid state materials. Here, we propose a new kind of interaction induced non-reciprocal operation, based on the conventional stimulated-Raman-adiabatic-passage (STIRAP) setup, which removes the experimental difficulty of requiring cyclical interaction, and thus it is directly implementable in various quantum systems. Furthermore, we also illustrate our proposal on a chain of three coupled superconducting transmons, which can lead to a non-reciprocal circulator with high fidelity without a ring coupling configuration as in the previous schemes or implementations. Therefore, our protocol provides a promising way to explore fundamental non-reciprocal quantum physics as well as realize non-reciprocal quantum device.
Realization and evaluation of the triple point of sulfur hexafluoride
Authors: Li Ting , Sun Jianping , Wang Hongjun , Yang Inseok , Hao Xiaopeng , Pan Jiang , Yang Jinnan , Ruan Yiming
Published: March 2021

In this study, we realized the triple point (TP) temperature of sulfur hexafluoride (SF6) at the National Institute of Metrology (NIM), China. To this end, we designed an iso-thermal and immersion type apparatus with an open cell with a height of 18 cm, diameter of 5 cm, and a capacity of approximately 275 ml. The cell was designed with four thermometer wells for the simultaneous temperature measurements with four standard platinum resistance thermometers (SPRTs). The cell is connected with two buffer tanks that allow a sufficient amount of SF6 to surround the thermometer wells during the solidification and melting processes to ensure stable temperature plateaus with long durations. An SF6 sample with a purity of 99.9997%, which is the highest purity currently available, was supplied and analyzed from the Korea Research Institute of Standards and Science. The SF6 TP temperature was determined using four long-stem SPRTs. The melting plateaus obtained had a duration longer than 15 h, and the TP temperature of SF6 was determined to be 223.556 03(54) K (k = 1). These results are consistent with those of previous studies and further indicate that the SF6 TP is a good candidate to replace mercury TP, which is one of the fixed points defined in the International Temperature Scale of 1990, for the calibration of SPRTs.
Numerical simulation of coalescence and break-up of drops in shear flow based on the meshless localized radial basis function method
Authors: Pranowo  , Tri Wijayanta Agung , Itaya Yoshinori
Published: March 2021

In the present paper, the meshless localized radial basis function (RBF) is proposed for simulating of two-phase incompressible viscous flow. Due to the velocity of the shear flow is very low, the fluid can modeled by Stokes equations. For more convenience the primitive variables, i.e., pressure and velocity components of the Stokes equations are transformed into stream function formulation. The interface of the fluid system is modeled by using Cahn-Hilliard equation. The spatial terms of the governing equations are discretized numerically by using the RBF method. The temporal term is integrated by using fully implicit Euler method. The nonlinear terms of Cahn-Hilliard equation is linearized using the Picard iteration. The proposed method is applied to simulate coalescence and break-up of drops in shear flow. The numerical results show that the deformation of the interface can be modeled without any difficulties.
Determination of Groundwater Potential in Pulutan Wetan Village Wuryantoro District Wonogiri Using Vertical Electrical Sounding Method
Authors: Amalia Khusna Iin , Koesuma Sorja , Darsono
Published: March 2021

The Pulutan Village is in the karst area consisting mostly of limestone so that during the dry season will cause drought. Drought caused by water is located below the surface so it is difficult to take and known location, it is necessary to investigate the presence of aquifer. The study aims to find out the structures beneath the surface, the depth of the aquifer, and to get cross-section results in 3-dimensional form. The method used in this research is the method of geoelectric resistivity with Schlumberger configuration using the 3 points sounding. The results of the study were obtained that aquifer is located on a coating of tuff sandstone with a resistivity between 2.40 ňm to 4.15 ňm. The second Sounding point, it is known that there is a large prospect of groundwater visible from the thickness of the aquifer layer.
The Influence of Non-Collinear Electrodes Arrangement on a Two-dimensional Resistivity Survey Using Wenner Array
Authors: Mohammed M A , Muztaza N M , Saad R
Published: March 2021

Conventional protocols employed by various multi-electrode resistivity systems are designed with the assumption that the survey lines are straight to ensure collinear electrode pairs. However, as most survey areas are characterized by surface constraints, it is rarely possible to carry out two-dimensional electrical resistivity tomography (2-DERT) measurement on a straight line. Therefore, 2-DERT surveys conducted on a surface constraint field requires shifting of some electrodes off the survey line, which implies a non-collinear electrodes arrangement. Hence, the result of such a survey is prone to false anomalies and in turn, wrong interpretation. This article aims to uncover the potential effect of non-collinear electrodes arrangement on 2-D resistivity survey. To achieve this goal, the data was acquired in four phases using Wenner array with all electrodes inline, one offline, two offline and three offline at stepwise distances, respectively. The inverse resistivity models obtained revealed slight to distinct variation of anomalies as two or more electrodes are offline at a distance >½ the minimum electrode spacing.
Geoelectrical survey and cone penetration test data for groundwater potential determination around Gatot Subroto Street, Banjarmasin
Authors: Archie Antareza Muhammad , Wafi Abdurrahman , Lasmana Yudi , Mariyanto Mariyanto
Published: March 2021

Subsurface condition evaluation is often relied to answer various necessities in a community, such as groundwater potential determination as a source of water supply. One of the most utilized method for this purpose is the geoelectrical method due to its efficiency, cost effectivity, and non-invasive nature. Geoelectrical method can also be used in tandem with geotechnical method, such as the Cone Penetration Test (CPT). In this study, a geoelectrical survey has been conducted in Gatot Subroto Street, Balikpapan. The survey uses 3 geoelectrical configurations: Dipole-Dipole, Wenner-Alpha, and Wenner-Schlumberger, which was performed using MAE type X-612EM+ with 24 electodes and 2 m spacing between electrodes. Soil quality assessment has also been conducted at the location from 0 to 29 m of depth using CPT. After geoelectrical survey had been done, the data would then be interpreted along with CPT data to project subsurface condition around the studied location. Based on the observation of the geoelectrical survey up to 6 m of depth, there are areas showing low resistivity value of <100 Ωm, characterizing that the layer is dominated by clay. In addition, groundwater potential is also found at a depth of ±2 m and characterized by a very low resistivity value of < 1.7 Ωm. Furthermore, CPT data classifies the soil layer from 0 to 19.40 m as very soft clay. These results infer strong correlation between geoelectrical and CPT data at the observed location.
Analytical comparison of electrode configuration on 2D geoelectric method for identification of water seepage in the lake body
Authors: Dwimanggala Tjiongnotoputera Kevin , Wafi Abdurrahman , Syarif Setiawan Nugroho , Mariyanto Mariyanto
Published: March 2021

The geoelectric method is a geophysical method based on the resistivity value of the material. The resistivity value gives an overview of the structure found at the observation site. The electrode configurations used are the Dipole-Dipole, Wenner-Alpha, Wenner-Schlumberger, and Pole-Dipole. The analytical measurement was carried out in the lake body with a track length of 48 meters. From the measurement results, we obtained a seepage of water in the lake body with a resistivity value <5 Ohmmeters. The observation site is dominated by clay type structure, which is found almost in all of the results of the geoelectric electrode configuration. Based on the results of the structural overview shows that the type of electrode configuration has advantages and disadvantages. The Wenner-Schlumberger configuration is very detailed with per layer structure and distribution but has the longest measurement time. Dipole-Dipole configuration has the advantage of being very sensitive to changes in vertical structure and the fastest measurement time, but not very good in horizontal structures. The Wenner-Alpha method is very sensitive to horizontal structural changes and has a moderate measurement time, but less sensitive to vertical structure changes. The pole-dipole configuration has a fast time and a moderate level of sensitivity at shallow depth. Based on the results, the Dipole-Dipole method is highly recommended because of the fast measurement time and the position of seepage can be found easier than the other methods.
The Electrical Resistivity Tomography Technique for Landslide Characterization in Blangkejeren Aceh
Authors: Zainal Muzakir , Munir Badrul , Marwan
Published: March 2021

Investigation of geophysical methods describes elements and geological geometry based on the physical properties of the subsurface. In the past decade, the application of resistivity methods has experienced a rapid increase in describing geological structures and settings. The Electrical Resistivity Tomography technique used to describe the geometry of a complex landslide in Blangkejeren, Aceh province, Indonesia. This area is highly influenced by the landscape with slopes, high-rainfall, and tectonic activity of the Sumatran fault which can lead to soil movement. The type of landslides in this area is largely controlled by geo-structural characteristics; rotational and translational slides, as well as the phenomenon of the gravitational slope of high steepness. As a preliminary study, the acquisition of resistivity data was conducted at two locations with a length of each measuring path 330 meters and electrodes spacing 6 meters. The Supersting R8/IP instrument unit with Wenner-Schlumberger array is used to obtain data that has a sensitivity to vertical and lateral changes. The resistivity distribution along the path is obtained from both profiles that are perpendicular to the landslide field. ERT modeling results at both locations showed subsurface structures based on resistivity values such as; slate, clay, and sandy clay. The contrast resistivity between each layer makes it easier to describe the characteristics of the landslide slip plane geometry which is affected by the slope angle. The resistivity method has physical properties that are very sensitive to porosity and groundwater which is the main parameter in a landslide. Finally, it should be noted that the use of the ERT technique as an effective and efficient method in conducting landslide studies as a disaster mitigation effort.
Development of Inhomogeneity Measurement System for Type T Thermocouple with Local Heating Method
Authors: Nugraha Heri , Prajitno Prawito , Achmadi Aditya , Sindhu Tistomo Arfan , Sukarto Wismogroho Agus , Imaduddin Agung , Dwi Yudanto Sigit , Herbirowo Satrio , Hendrik  , Roberto Rahadian
Published: March 2021

The voltage of thermocouple during process contribution is determined by the absolute thermal electromotive force coefficient in each wire and the temperature difference across the section. This paper described the development of a system as a local heating method for measurements of inhomogeneities in type T thermocouples with various temperature scanning using hot air. The system could control automatically measurement voltage, temperature, distance, and speed of the stepper motor for moving the hot air scanning along with the thermocouple and control with temperature monitoring. Both the measuring and reference junctions were using an ice bath kept at 0 °C. In this paper calculation of interpretation of the measurement results of inhomogeneity using movable heating zone system of type T thermocouples and the system could detected inhomogeneity of thermocouple and there have different characteristics of voltage and seebeck effect.
Photoplethysmogram peaks detection based on moving window integration and threshold for heart rate calculation on android smartphone
Authors: Utomo T P , Nuryani N
Published: March 2021

We present a photoplethysmogram peaks detection and heart rate calculation on android smartphone. Photoplethysmogram signal is obtained and extracted from a video stream of fingertip that is taken from smartphone camera. Then, photoplethysmogram peak is detected based on moving window integration and threshold. The heart rate value is calculated from the detected peak. We design an Android Application for processing photoplethysmogram data and calculating the Heart Rate. The photoplethysmogram signal and detected peak could be saved in smartphone’s storage and uploaded to the existing database. Peak detection and peak to peak time interval calculation are successfully conducted. The performance of the peak detection is calculated in terms of accuracy, sensitivity, and positive predictive. Positive predictive, accuracy, and sensitivity of peak detection are 99.19%, 92.45%, 93.17%, respectively.
SNR on the Four Probe Measurement System at Earth Surface
Authors: Hidayat Samsul , Santoso Didik R , Maryanto Sukir , Nadhir Ahmad
Published: March 2021

In the real world, the presence of noise is undeniable. Electric fields, magnetic fields, temperature changes, atomic structures, and so forth are contributing to the reality and the magnitude of noise. Data acquisition of physical quantities in nature is always needed, which subsequently is required for the interpretation in the laboratory. For this reason, the presence of noise needs to be eliminated or known. In the four-probe measurement system, the two electrodes are injecting current, while the other two electrodes are used for acquisition of the arising voltage. The voltage that arises is greatly influenced by the natural environment and the conductor cables, which are usually in long spans and unprotected. For this reason, noise minimization is very needed. This study aims to compare several types of conductors in reducing noise and reducing attenuation. The study was conducted in an open field with a 20-meter cable, and the front-end amplifier was varied to get the highest SNR.
nRF24L01 Distance and Error Link when Operated on Orange Plant Garden
Authors: Bayu Adetya Falen , Hidayat Samsul , Al Fansyuri Buyung
Published: March 2021

The environmental conditions of the plantation area significantly affect the quantity and quality of fruit. Not only that, but the survival of plants will also be supported by the support of environmental conditions. Nowadays, wireless technology is proliferating. Wi-fi, remote control, cell phones are wireless technology products. Wireless technology was developed on the use of electromagnetic waves as a career for the data transmission. Electromagnetic waves are strongly influenced by the medium in its propagation but do not need a medium to propagate. Data will not be received/sent if electromagnetic waves are obstructed. Buildings, metal plates, leaves, trees will provide different attenuation of the electromagnetic waves. Wireless technology is beneficial if applied in plantation areas. In this study, research has been conducted on data errors due to the environment and distances that are out of reach. The primary device as a sender and receiver of data is the nRF24L01 module, which works at 2.4 GHz frequency. Data cannot be sent/received at close range because it is blocked by a building, and can reach one kilometer when used on the outskirts of the Malang Balitjestro orange plantation.
Design a battery management system (BMS) with an automatic cut off system on LFP (LiFePO4) battery type for powerbank application
Authors: Nur Putra Agustina Muhammad , Dwijo Sutomo Artono , Widiyandari Hendri
Published: March 2021

A battery is a cell device that can store energy and be converted into a constant voltage. Overcharging and over-discharging conditions on the battery are often a problem. This research designed a Battery Management System (BMS) to monitor battery performance with an automatic Cut Off system. The prototype system uses a voltage divider circuit in the voltage measurement process, one channel relay as the process of cutting off the electric current and Arduino UNO microcontroller as a data processor. Testing on five cell LiFePO4 (LFP) 3.2 volt battery with 1200 mAh capacity using the charging and discharging method in measuring the battery voltage. The results of measuring the voltage in the charging process take 2 hours 25 minutes to reach a voltage of 3.26 V obtained an average error value of each cell measurement of 0.44%. While the discharging process, to reach the voltage of 2.00 V, required an emptying time of 7 hours 15 minutes for output without step-up and 2 hours 46 minutes for the output with step-up obtained an average measurement error value of each cell 1.11% and 1.39%.
Photoluminesence study of undoped GaAs at temperatures 300 K and 77 K
Authors: Amaliya V F , Yuniati A , van Dommelen P
Published: March 2021

This work presents an experimental study of photoluminescence spectra from GaAs thin layer at temperature 300 K and 77 K. PL spectra were used to investigate the characteristics of the material, such as the photon energy, gap energy, and the type of radiation transition. The apparatus used in the experiment are green laser with a wavelength of 532.0 nm, laser power supply, 500 mm focus lens, ocean optics USB 2000 spectrometer, fiber optic cable, USB cable, and the computer software installed ocean view and origin pro. The characterization was carried out at temperatures of 300 K and 77 K with power variation in the range 40 mW - 150 mW. The emitted spectrum was analyzed by observing the wavelength and calculating the photon energy and the gap energy. The results showed that laser power variation does not affect the emitted wavelength. However, it is affected by temperature. The emitted wavelength is 840 nm at 300 K and 790 nm at 77 K. The value of gap energy at 300 K is 1.422 eV while at temperature 77 K is 1.519 eV. The photon energy at temperatures 300 K and 77 K were 1.465 eV and 1.560 eV, respectively. The type of transition is a band-to-band transition at 300 K and Free Exciton (FE) at 77K. These results are consistent with existing theories, so the characterization of undoped GaAs has done successfully.
Effect of pyrolysis temperature on bio-fuel quality produced from pine bark (Pinus merkusii) by pyro-catalytics method
Authors: Jahiding M , Arsyad W O S , Rif’ah S M , Rizki R S , Mashuni
Published: March 2021

This study aims to determine the effect of pyro-catalytic temperature on the quality of bio-fuel. Bio-fuel quality analysis includes: density, viscosity, calorific value, and composition of hydrocarbon compounds using Gas Chromatrography-Mass Spectrometry (GC-MS). The pyro-catalytic process was carried out at a temperature variation of 400, 500 and 600° C with each addition of 5% zeolite catalyst to the mass of the sample used. Results showed the best bio-fuels were obtained at a temperature of 500° C with viscosity of 21.39 cP, density of 0.9884 gr / ml and calorific value of 10.367 kcal / kg. Analysis composition of fuel content in bio-fuel using GC-MS obtained acetic acid, phenol, furfural, pyridine, creosol, benzene, ethanol and cathecol with a fuel percentage of 66.51% at 500° C, so as to produce bio-fuel from Pine bark (Pinus mercusii) can be used as an energy source (alternative fuel).
Determination of Electron Excitation Temperature in an RF-DC Hollow Cathode Nitrogen Plasma
Authors: Windajanti J M , Santjojo D J D H , Pamungkas M A , Abdurrouf
Published: March 2021

An RF-DC nitrogen glow discharge generated inside a rectangular hollow cathode was investigated as a source of nitrogen atoms. The plasma was produced at a frequency of 2 MHz at a low-pressure condition at the range of 30 to 100 Pa. The power generator was controlled at the RF voltage of 150 V and DC bias voltage of -500 V. The atomic nitrogen species have been detected by employing an optical emission spectroscopy technique. The use of a rectangular hollow cathode proves that the increase of nitrogen atoms species at a wavelength range of 700-900 nm was produced from the dissociation process of molecular nitrogen species. The present work aims to determine the electron excitation temperature based on the OES spectra. The excitation temperature was calculated by using the Boltzmann plot method. The result is the excitation temperature determined at the range of 0.59 to 0.71 eV. The excitation temperature in the hollow cathode was decreased with the increasing pressure.
Effect of Nd3+ substitution on the BHmax properties of barium-strontium hexaferrite permanent magnet
Authors: Gunanto Y E , Izaak M P , Sitompul H , Adi W A
Published: March 2021

This paper describes the effect of the substitution of Nd3+ ions in Barium-Strontium Hexaferrite (Ba0.6Sr0.4)1-xNdxFe12O19 with x = 0.01, 0.03 and 0.05, on the energy of the product. All samples were made from raw materials of barium (II) carbonate, strontium (II) carbonate, neodymium (III) oxide, and iron (III) oxide which each have a purity of > 99% which was processed by the solid-state reaction method using high energy milling with a rotating speed of 750 rpm.The crystal structure and phase formed are characterized using an X-ray diffractometer. Scanning electron microscopy is used for surface morphology analysis and permagraph is used for hysteresis characterization so that the product energy can be calculated. X-ray diffraction analysis showed that all phase samples have an orthorhombic structure and space group P nma. Surface morphology is almost homogeneous with heterogeneous shapes and the average particle size ranges from 200-800 nm. The maximum product energy obtained is 165.4kGOe in the sample x = 0.05.