bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of channel width on droplet generation inside T-junction microchannel
Authors: Jena Santosh Kumar , Srivastava Tushar , Bahga Supreet Singh , Kondaraju Sasidhar
Published: January 2023

In a T-junction microchannel, channel geometry plays a major role that affects the physics behind droplet generation. The effect of channel width on droplet size and frequency in a T-junction microchannel is investigated in the present study. The current work is an extension of our previous work, where a model was developed to predict the size of the droplets generated in a T-junction microchannel when both the continuous and dispersed phase channels have equal widths. In the present work, we extended the model to account for the varying width ratio between the dispersed and continuous phase channels. We performed in-house experiments by varying the channel width and viscosity ratios between the fluids to study the size of the droplets generated and to validate the proposed scaling law. We further investigated the effect of channel geometry on the frequency of droplet generation in the T-junction microchannels. The experimental results show that the droplet length increases with an increase in the width of the continuous phase channel. On the other hand, the droplet production frequency decreases with an increase in the width of the continuous phase channel. With variations in the width of the dispersed phase channel, similar behavior in droplet sizes and the frequency of droplet production is observed. The analysis of this study provides new insight into the effect of channel width on the droplet length and frequency. Overall, this research intends to provide a thorough understanding of the design of microchannels based on the geometry and manipulation of droplets with varying widths.
Enhanced carrier management via optimized SnO2 preparation and film coverage for improved device performance
Authors: Liu Xiangyang , Liu Xinsheng , Ma Zhaohua , Liang Siyang , Qin Chaoran , Zhi Guolin , Li Weikun
Published: January 2023

Optimized electron transport layers (ETLs) can highly promote charge extraction and reduce carrier depopulation. Herein, tin oxide (SnO2) nanocrystals were prepared with the addition of citric acid to suppress SnO2 aggregation and achieve complete film coverage. The dense and uniform SnO2 films with smaller grain sizes will apparently enhance the external quantum efficiency and alleviate the J–V hysteresis behavior. The improved SnO2 film coverage can also passivate traps at ETL/perovskite interfaces and markedly suppress charge recombination to promote rapid carrier injection from perovskite to SnO2. Surely, the optimized SnO2 shows better electrical properties and device performance than Alfa-SnO2. In addition, the diblock-polymer of (PEO)120-(PPO)30 was incorporated into perovskite films to passivate defects and improve device stability. A power conversion efficiency of 23.12% [a VOC of 1.164 V, a JSC of 24.46 mA cm−2, and a fill factor (FF) of 0.812] for the best-performing device is achieved. The charge dynamics (separation, transport, and extraction) were also analyzed using characterization techniques. The optimized device will largely enhance carrier management and light-harvesting performance, and the controlled SnO2 can also open up an effective way to achieve scalable preparation and commercialization of perovskite solar cells.
Electrophoretic motion of hydrophobic spherical particles in nanopore: Characteristics, separation, and resistive pulse sensing
Authors: Shafiei Souderjani Ali , Bakouei Mostafa , Saidi Mohammad Hassan , Taghipoor Mojtaba
Published: January 2023

Electrophoretic motion of hydrophobic particles has been scrutinized numerically in solid-state nanopores. The Poisson, Stokes, and Nernst–Planck equations are solved simultaneously, and the Newton–Raphson algorithm is used to compute the correct velocity at each point. For the hydrophobic surface characterization, the Navier-slip boundary condition with a wide range of slip lengths is applied to the nanoparticle's surface. The effects of the electric field intensity, the electrolyte concentration, and the particle's size on the electrophoretic velocity are examined. Then, the nanopore's size and surface charge density are manipulated to achieve the configuration for separating hydrophobic and hydrophilic particles based on their slip lengths. The results show that the hydrophobic and hydrophilic particles, under particular circumstances, would move in the opposite direction in a nanopore. Finally, the resistive pulses of the particles with various slip lengths are studied. The resistive pulse properties of the hydrophobic and the hydrophilic particles are completely distinguishable and show potential application for resistive pulse sensing as a tool for reckoning the particle's slip length.
An asymptotic matching approach to the approximate solution of the Blasius problem
Authors: Durante Danilo
Published: January 2023

The Blasius equation dates back to the early twentieth century and describes the boundary layer caused by a uniform flow over a flat plate. Due to the asymptotic condition on the first derivative of the solution, the problem is not an initial value one. The non-linear nature of the equation has led many authors to exploit approximation strategies to obtain an estimate of the solution. Several papers deal with series expansions, but the solutions are partly numerical and do not converge rapidly everywhere. In the present paper, a strategy is proposed to obtain an approximate solution of the Blasius problem in the closed form, i.e., without the use of series expansions. Motivated by the asymptotic behavior of the second derivative, a parametric definition of the third derivative of the Blasius solution is introduced and successive integrations are performed. By imposing the expected asymptotic conditions, a final approximate solution is obtained. This latter has the notable advantage of possessing the same behavior at 0 and at ∞ as the analytical solution up to the third derivative. It will also be shown how this result can be extended to the Falkner–Skan problem with non-zero pressure gradient and provide an accurate estimation of the thermal boundary layer over a flat plate under isothermal and adiabatic conditions.
Structural OFF/ON transitions of myosin in relaxed porcine myocardium predict calcium-activated force
Authors: Ma Weikang , McMillen Timothy S. , Childers Matthew Carter , Gong Henry , Regnier Michael , Irving Thomas
Published: January 2023

Contraction in striated muscle is initiated by calcium binding to troponin complexes, but it is now understood that dynamic transition of myosin between resting, ordered OFF states on thick filaments and active, disordered ON states that can bind to thin filaments is critical in regulating muscle contractility. These structural OFF to ON transitions of myosin are widely assumed to correspond to transitions from the biochemically defined, energy-sparing, super-relaxed (SRX) state to the higher ATPase disordered-relaxed (DRX) state. Here we examined the effect of 2’-deoxy-ATP (dATP), a naturally occurring energy substrate for myosin, on the structural OFF to ON transitions of myosin motors in porcine cardiac muscle thick filaments. Small-angle X-ray diffraction revealed that titrating dATP in relaxation solutions progressively moves the myosin heads from ordered OFF states on the thick filament backbone to disordered ON states closer to thin filaments. Importantly, we found that the structural OFF to ON transitions are not equivalent to the biochemically defined SRX to DRX transitions and that the dATP-induced structural OFF to ON transitions of myosin motors in relaxed muscle are strongly correlated with submaximal force augmentation by dATP. These results indicate that structural OFF to ON transitions of myosin in relaxed muscle can predict the level of force attained in calcium-activated cardiac muscle. Computational modeling and stiffness measurements suggest a final step in the OFF to ON transition may involve a subset of DRX myosins that form weakly bound cross-bridges prior to becoming active force-producing cross-bridges.
Ufmylation reconciles salt stress-induced unfolded protein responses via ER-phagy in
Arabidopsis
Authors: Li Baiying , Niu Fangfang , Zeng Yonglun , Tse Man Kei , Deng Cesi , Hong Liu , Gao Shengyu , Lo Sze Wan , Cao Wenhan , Huang Shuxian , Dagdas Yasin , Jiang Liwen
Published: January 2023

In plants, the endomembrane system is tightly regulated in response to environmental stresses for maintaining cellular homeostasis. Autophagosomes, the double membrane organelles forming upon nutrient deprivation or stress induction, degrade bulky cytosolic materials for nutrient turnover. Though abiotic stresses have been reported to induce plant autophagy, few receptors or regulators for selective autophagy have been characterized for specific stresses. Here, we have applied immunoprecipitation followed by tandem mass spectrometry using the autophagosome marker protein ATG8 as bait and have identified the E3 ligase of the ufmylation system Ufl1 as a bona fide ATG8 interactor under salt stress. Notably, core components in the ufmylation cascade, Ufl1 and Ufm1, interact with the autophagy kinase complexes proteins ATG1 and ATG6. Cellular and genetic analysis showed that Ufl1 is important for endoplasmic reticulum (ER)-phagy under persisting salt stress. Loss-of-function mutants of Ufl1 display a salt stress hypersensitive phenotype and abnormal ER morphology. Prolonged ER stress responses are detected in
ufl1
mutants that phenocopy the autophagy dysfunction
atg5
mutants. Consistently, expression of ufmylation cascade components is up-regulated by salt stress. Taken together, our study demonstrates the role of ufmylation in regulating ER homeostasis under salt stress through ER-phagy.
The fidelity of transcription in human cells
Authors: Chung Claire , Verheijen Bert M. , Zhang Xinmin , Huang Biao , Coakley Aeowynn , McGann Eric , Wade Emily , Dinep-Schneider Olivia , LaGosh Jessica , Anagnostou Maria-Eleni , Simpson Stephen , Thomas Kelly , Ernst Mimi , Rattray Allison , Lynch Michael , Kashlev Mikhail , Benayoun Berenice A. , Li Zhongwei , Strathern Jeffrey , Gout Jean-Francois , Vermulst Marc
Published: January 2023

To determine the error rate of transcription in human cells, we analyzed the transcriptome of H1 human embryonic stem cells with a circle-sequencing approach that allows for high-fidelity sequencing of the transcriptome. These experiments identified approximately 100,000 errors distributed over every major RNA species in human cells. Our results indicate that different RNA species display different error rates, suggesting that human cells prioritize the fidelity of some RNAs over others. Cross-referencing the errors that we detected with various genetic and epigenetic features of the human genome revealed that the in vivo error rate in human cells changes along the length of a transcript and is further modified by genetic context, repetitive elements, epigenetic markers, and the speed of transcription. Our experiments further suggest that BRCA1, a DNA repair protein implicated in breast cancer, has a previously unknown role in the suppression of transcription errors. Finally, we analyzed the distribution of transcription errors in multiple tissues of a new mouse model and found that they occur preferentially in neurons, compared to other cell types. These observations lend additional weight to the idea that transcription errors play a key role in the progression of various neurological disorders, including Alzheimer’s disease.
Molecular DNA dendron vaccines
Authors: Distler Max E. , Cavaliere John P. , Teplensky Michelle H. , Evangelopoulos Michael , Mirkin Chad A.
Published: January 2023

A foundational principle of rational vaccinology is that vaccine structure plays a critical role in determining therapeutic efficacy, but in order to establish fundamental, effective, and translatable vaccine design parameters, a highly modular and well-defined platform is required. Herein, we report a DNA dendron vaccine, a molecular nanostructure that consists of an adjuvant DNA strand that splits into multiple DNA branches with a varied number of conjugated peptide antigens that is capable of dendritic cell uptake, immune activation, and potent cancer killing. We leveraged the well-defined architecture and chemical modularity of the DNA dendron to study structure-function relationships that dictate molecular vaccine efficacy, particularly regarding the delivery of immune-activating DNA sequences and antigenic peptides on a single chemical construct. We investigated how adjuvant and antigen placement and number impact dendron cellular uptake and immune activation, in vitro. These parameters also played a significant role in raising a potent and specific immune response against target cancer cells. By gaining this structural understanding of molecular vaccines, DNA dendrons successfully treated a mouse cervical human papillomavirus TC-1 cancer model, in vivo, where the vaccine structure defined its efficacy; the top-performing design effectively reduced tumor burden (<150 mm
3
through day 30) and maintained 100% survival through 44 d after tumor inoculation.
Structural and functional insights into the chloroplast division site regulators PARC6 and PDV1 in the intermembrane space
Authors: Sun Qingqing , Cao Xueli , Liu Zihe , An Chuanjing , Hu Jinglei , Wang Yue , Qiao Meiyu , Gao Teng , Cheng Wenzhen , Zhang Yi , Feng Yue , Gao Hongbo
Published: January 2023

Chloroplast division involves the coordination of protein complexes from the stroma to the cytosol. The Min system of chloroplasts includes multiple stromal proteins that regulate the positioning of the division site. The outer envelope protein PLASTID DIVISION1 (PDV1) was previously reported to recruit the cytosolic chloroplast division protein ACCUMULATION AND REPLICATION OF CHLOROPLAST5 (ARC5). However, we show here that PDV1 is also important for the stability of the inner envelope chloroplast division protein PARALOG OF ARC6 (PARC6), a component of the Min system. We solved the structure of both the C-terminal domain of PARC6 and its complex with the C terminus of PDV1. The formation of an intramolecular disulfide bond within PARC6 under oxidized conditions prevents its interaction with PDV1. Interestingly, this disulfide bond can be reduced by light in planta, thus promoting PDV1–PARC6 interaction and chloroplast division. Interaction with PDV1 can induce the dimerization of PARC6, which is important for chloroplast division. Magnesium ions, whose concentration in chloroplasts increases upon light exposure, also promote the PARC6 dimerization. This study highlights the multilayer regulation of the PDV1–PARC6 interaction as well as chloroplast division.
Cryo-EM structure of human voltage-gated sodium channel Na
v
1.6
Authors: Fan Xiao , Huang Jian , Jin Xueqin , Yan Nieng
Published: January 2023

Voltage-gated sodium channel Na
v
1.6 plays a crucial role in neuronal firing in the central nervous system (CNS). Aberrant function of Na
v
1.6 may lead to epilepsy and other neurological disorders. Specific inhibitors of Na
v
1.6 thus have therapeutic potentials. Here we present the cryo-EM structure of human Na
v
1.6 in the presence of auxiliary subunits β1 and fibroblast growth factor homologous factor 2B (FHF2B) at an overall resolution of 3.1 Å. The overall structure represents an inactivated state with closed pore domain (PD) and all “up” voltage-sensing domains. A conserved carbohydrate–aromatic interaction involving Trp302 and Asn326, together with the β1 subunit, stabilizes the extracellular loop in repeat I. Apart from regular lipids that are resolved in the EM map, an unprecedented Y-shaped density that belongs to an unidentified molecule binds to the PD, revealing a potential site for developing Na
v
1.6-specific blockers. Structural mapping of disease-related Na
v
1.6 mutations provides insights into their pathogenic mechanism.
A nucleotide binding–independent role for γ-tubulin in microtubule capping and cell division
Authors: Berman Adi Y. , Wieczorek Michal , Aher Amol , Olinares Paul Dominic B. , Chait Brian T. , Kapoor Tarun M.
Published: January 2023

The γ-tubulin ring complex (γ-TuRC) has essential roles in centrosomal and non-centrosomal microtubule organization during vertebrate mitosis. While there have been important advances in understanding γ-TuRC-dependent microtubule nucleation, γ-TuRC capping of microtubule minus-ends remains poorly characterized. Here, we utilized biochemical reconstitutions and cellular assays to characterize the human γ-TuRC’s capping activity. Single filament assays showed that the γ-TuRC remained associated with a nucleated microtubule for tens of minutes. In contrast, caps at dynamic microtubule minus-ends displayed lifetimes of ∼1 min. Reconstituted γ-TuRCs with nucleotide-binding deficient γ-tubulin (γ-tubulinΔGTP) formed ring-shaped complexes that did not nucleate microtubules but capped microtubule minus-ends with lifetimes similar to those measured for wild-type complexes. In dividing cells, microtubule regrowth assays revealed that while knockdown of γ-tubulin suppressed non-centrosomal microtubule formation, add-back of γ-tubulinΔGTP could substantially restore this process. Our results suggest that γ-TuRC capping is a nucleotide-binding-independent activity that plays a role in non-centrosomal microtubule organization during cell division.
Real-time observation of functional specialization among phosphorylation sites in CFTR
Authors: Infield Daniel T. , Schene Miranda E. , Fazan Frederico S. , Galles Grace D. , Galpin Jason D. , Ahern Christopher A.
Published: January 2023

Phosphoregulation is ubiquitous in biology. Defining the functional roles of individual phosphorylation sites within a multivalent system remains particularly challenging. We have therefore applied a chemical biology approach to light-control the state of single candidate phosphoserines in the canonical anion channel CFTR while simultaneously measuring channel activity. The data show striking non-equivalency among protein kinase A consensus sites, which vary from <10% to >1,000% changes in channel activity upon phosphorylation. Of note, slow phosphorylation of S813 suggests that this site is rate-limiting to the full activation of CFTR. Further, this approach reveals an unexpected coupling between the phosphorylation of S813 and a nearby site, S795. Overall, these data establish an experimental route to understanding roles of specific phosphoserines within complex phosphoregulatory domains. This strategy may be employed in the study of phosphoregulation of other eukaryotic proteins.
Gravitational-gauge vector interaction in the Hořava–Lifshitz framework
Authors: Restuccia Alvaro , Tello-Ortiz Francisco
Published: January 2023

An anisotropic model describing gravity-vector gauge coupling at all energy scales is presented. The starting point is the 4+1 dimensional non–projectable Hořava–Lifshitz gravity theory subject to a geometrical restriction. Renormalizability arguments require all possible interactions in the potential up to terms with z = 4 spatial derivatives on the geometrical tensor fields: the Riemann and Weyl tensors. The latter being necessary on a 4+1 dimensional formulation. The dimensional reduction to 3+1 dimensions gives rise to a model invariant under foliation-preserving diffeomorphisms (FDiff) and U(1) symmetry groups. The reduced theory on the kinetic conformal point (

λ
=
1

/

3

), propagates the same spectrum of the Einstein–Maxwell theory. Moreover, at low energies, on the IR point α = 0, β = 1, its field equations are exactly the Einstein–Maxwell ones in a particular gauge condition. The Minkowski ground state is stable provided several restrictions on the coupling parameters are satisfied, they are explicitly obtained. The quantum propagators of the physical degrees of freedom are obtained and after an analysis of the first and second class constraints the renormalizability by power counting is proved, provided that the aforementioned restrictions on the coupling parameters are satisfied.
Global conformal diagram of a black hole with angular momentum
Authors: Argañaraz Marcos A , Moreschi Osvaldo M
Published: January 2023

We present the first explicit global conformal diagram of Kerr spacetime and discuss some implications on the causal structure. For this construction we use a new double null coordinate system for Kerr spacetime, which we have recently presented. These null coordinates are smooth everywhere and are naturally adapted to the horizons and to the null infinities. In this setting there naturally appears a family of spheres that are parameterized by r

s
, which are the intersections of both null coordinates, and r

s
can be thought of as the extension of the tortoise coordinate for the Kerr spacetime.
Performance comparison of x-ray absorption gratings fabricated by free deposition and centrifugal filling methods
Authors: Lei Yaohu , Li Xiqi , Xu Guiwen , Feng Chengming , Huang Jianheng , Liu Xin , Li Ji
Published: January 2023

Free deposition and centrifugal filling methods are commonly used to fill metal particles into grating trenches for long-period x-ray absorption gratings. However, there has been no comparative analysis on the performance of absorption gratings fabricated by the two filling methods, and the difference between the two methods is not well understood. This paper compares the free deposition and centrifugal filling methods through the x-ray absorptivity of absorption gratings and the arrangement of tungsten nanoparticles (TNs) in grating trenches. It has been found that both particle filling methods densely arrange TNs in grating trenches differently but give almost equal x-ray absorptivity to the resulting gratings. The experimental results indicate that a centrifugal filling method is efficient for manufacturing x-ray absorption gratings with stable absorptivity. Furthermore, to verify the feasibility of the centrifugal filling process in fabricating short-period TNs-based absorption gratings, an absorption grating with a 10 μm period is manufactured by removing large-size TNs using centrifugal force. Hence, it has the potential to be used for the fabrication of absorption gratings with periods of several micrometers.
Accelerating physics-informed neural network based 1D arc simulation by meta learning
Authors: Zhong Linlin , Wu Bingyu , Wang Yifan
Published: January 2023

Physics-informed neural networks (PINNs) have a wide range of applications as an alternative to traditional numerical methods in plasma simulation. However, in some specific cases of PINN-based modeling, a well-trained PINN may require tens of thousands of optimizing iterations during training stage for complex modeling and huge neural networks, which is sometimes very time-consuming. In this work, we propose a meta-learning method, namely Meta-PINN, to reduce the training time of PINN-based 1D arc simulation. In Meta-PINN, the meta network is first trained by a two-loop optimization on various training tasks of plasma modeling, and then used to initialize the PINN-based network for new tasks. We demonstrate the power of Meta-PINN by four cases corresponding to 1D arc models at different boundary temperatures, arc radii, arc pressures, and gas mixtures. We found that a well-trained meta network can produce good initial weights for PINN-based arc models even at conditions slightly outside of training range. The speed-up in terms of relative L2 error by Meta-PINN ranges from 1.1× to 6.9× in the cases we studied. The results indicate that Meta-PINN is an effective method for accelerating the PINN-based 1D arc simulation.
Ultralow-threshold quasi-CW lasing from FAPbBr3 perovskite first-order DFB laser
Authors: Chang Cheng , Lin Lih Y
Published: January 2023

Metal halide perovskites are emerging materials for integrated photonics. Here we report a quasi-CW pumped ultra-low ASE/lasing threshold formamidinium lead bromide (FAPbBr3) laser. The laser achieved stable lasing at 555 nm with a full width at half maximum (FWHM) of 0.6 nm, showing a low lasing threshold of 22.6 μJ cm−2 under 3.5 nanosecond quasi-CW excitation at room temperature. The material also showed an ultra-low ASE threshold of 46 μJ cm−2 under the same pumping condition. Through polymer doping, we showed that the material’s performance can be improved by increasing bimolecular recombination rate with reduced grain size.
Characterization of LiF:Mg,Ti thermoluminescence detectors in low-LET proton beams at ultra-high dose rates
Authors: Motta S , Christensen J B , Togno M , Schäfer R , Safai S , Lomax A J , Yukihara E G
Published: January 2023

Objective. This work aims at characterizing LiF:Mg,Ti thermoluminescence detectors (TLDs) for dosimetry of a 250 MeV proton beam delivered at ultra-high dose rates (UHDR). Possible dose rate effects in LiF:Mg,Ti, as well as its usability for dosimetry of narrow proton beams are investigated. Approach. LiF:Mg,Ti (TLD-100TM Microcubes, 1 mm × 1 mm × 1 mm) was packaged in matrices of 5 × 5 detectors. The center of each matrix was irradiated with single-spot low-LET (energy >244 MeV) proton beam in the (1–4500) Gy s−1 average dose rates range. A beam reconstruction procedure was applied to the detectors irradiated at the highest dose rate (Gaussian beam sigma <2 mm) to correct for volumetric averaging effects. Reference dosimetry was carried out with a diamond detector and radiochromic films. The delivered number of protons was measured by a Faraday cup, which was employed to normalize the detector responses. Main results. The lateral beam spread obtained from the beam reconstruction agreed with the one derived from the radiochromic film measurements. No dose rates effects were observed in LiF:Mg,Ti for the investigated dose rates within 3% (k = 1). On average, the dose response of the TLDs agreed with the reference detectors within their uncertainties. The largest deviation (−5%) was measured at 4500 Gy s−1. Significance. The dose rate independence of LiF:Mg,Ti TLDs makes them suitable for dosimetry of UHDR proton beams. Additionally, the combination of a matrix of TLDs and the beam reconstruction can be applied to determine the beam profile of narrow proton beams.
Development of optimised tissue-equivalent materials for proton therapy
Authors: Cook H , Simard M , Niemann N , Gillies C , Osborne M , Hussein M , Rompokos V , Bouchard H , Royle G , Pettingell J , Palmans H , Lourenço A
Published: January 2023

Objective. In proton therapy there is a need for proton optimised tissue-equivalent materials as existing phantom materials can produce large uncertainties in the determination of absorbed dose and range measurements. The aim of this work is to develop and characterise optimised tissue-equivalent materials for proton therapy. Approach. A mathematical model was developed to enable the formulation of epoxy-resin based tissue-equivalent materials that are optimised for all relevant interactions of protons with matter, as well as photon interactions, which play a role in the acquisition of CT numbers. This model developed formulations for vertebra bone- and skeletal muscle-equivalent plastic materials. The tissue equivalence of these new materials and commercial bone- and muscle-equivalent plastic materials were theoretical compared against biological tissue compositions. The new materials were manufactured and characterised by their mass density, relative stopping power (RSP) measurements, and CT scans to evaluate their tissue-equivalence. Main results. Results showed that existing tissue-equivalent materials can produce large uncertainties in proton therapy dosimetry. In particular commercial bone materials showed to have a relative difference up to 8% for range. On the contrary, the best optimised formulations were shown to mimic their target human tissues within 1%–2% for the mass density and RSP. Furthermore, their CT-predicted RSP agreed within 1%–2% of the experimental RSP, confirming their suitability as clinical phantom materials. Significance. We have developed a tool for the formulation of tissue-equivalent materials optimised for proton dosimetry. Our model has enabled the development of proton optimised tissue-equivalent materials which perform better than existing tissue-equivalent materials. These new materials will enable the advancement of clinical proton phantoms for accurate proton dosimetry.
Fatigue life analysis and damage evaluation in glass fiber reinforced composite materials based on recycled polyethylene terephthalate
Authors: Singh Ashwani Kumar , Bedi Raman
Published: January 2023

Viability of recycling polyethylene terephthalate (PET) can be enhanced by increasing its usage as a matrix material in manufacturing of composite materials. Structural applications of composite materials almost always involve fatigue loading and evaluation of fatigue behaviour is essential to explore the full potential of composite materials based on recycled PET. With an aim to increase the acceptability of recycled PET based resins, fatigue performance of glass fiber reinforced composite materials based on unsaturated polyester resin derived from recycled PET (rPET-UPR) has been evaluated in the present research. Glass fiber composites laminates of stacking sequence [0/(±45)2/0]Thave been fabricated using vacuum infusion process. Fatigue tests were performed at the stress ratio of 0.1, where the stress level varied from 40%–80% of the ultimate tensile strength (UTS). The results of fatigue tests show that the fatigue lives of composites based on rPET-UPR were lower as compared to virgin polyester matrix composites. However, Statistical analysis of the fatigue life data using two parameter Weibull distribution, established that there is no deleterious effect on the scatter observed in fatigue lives of these composites, as compared to composites based on virgin polyester resin. Due to higher degradation of rPET-UPR matrix as well as weak interfacial properties, 13% higher self generated temperature was observed during fatigue loading in comparison to virgin resin based composite materials. A three phase stiffness degradation curve has been observed for these composite materials indicating stiffness loss in the range of 20%–35% till the time of failure, which correlates well with the experimental damage observations. A nonuniform and rapid damage growth was observed at high-stress levels, whereas a more uniform damage zone was observed at the low-stress levels.
Neutrino propagation in the Earth and emerging charged leptons with nuPyProp
Authors: Garg Diksha , Patel Sameer , Reno Mary Hall , Reustle Alexander , Akaike Yosui , Anchordoqui Luis A. , Bergman Douglas R. , Buckland Isaac , Cummings Austin L. , Eser Johannes , Garcia Fred , Guépin Claire , Heibges Tobias , Ludwig Andrew , Krizmanic John F. , Mackovjak Simon , Mayotte Eric , Mayotte Sonja , Olinto Angela V. , Paul Thomas C. , Romero-Wolf Andrés , Sarazin Frédéric , Venters Tonia M. , Wiencke Lawrence , Wissel Stephanie
Published: January 2023

Ultra-high-energy neutrinos serve as messengers of some of the highest energy astrophysical environments. Given that neutrinos are neutral and only interact via weak interactions, neutrinos can emerge from sources, traverse astronomical distances, and point back to their origins. Their weak interactions require large target volumes for neutrino detection. Using the Earth as a neutrino converter, terrestrial, sub-orbital, and satellite-based instruments are able to detect signals of neutrino-induced extensive air showers. In this paper, we describe the software code nuPyProp that simulates tau neutrino and muon neutrino interactions in the Earth and predicts the spectrum of the τ-leptons and muons that emerge. The nuPyProp outputs are lookup tables of charged lepton exit probabilities and energies that can be used directly or as inputs to the nuSpaceSim code designed to simulate optical and radio signals from extensive air showers induced by the emerging charged leptons. We describe the inputs to the code, demonstrate its flexibility and show selected results for τ-lepton and muon exit probabilities and energy distributions. The nuPyProp code is open source, available on github.
Influences of plasma density perturbations on ion cyclotron resonance heating
Authors: Zhang J.H. , Zhang W. , Zhang X.J. , Qin C.M. , Yang Y.Q. , Shi L.
Published: January 2023

The scattering of waves in the ion cyclotron range by plasma density perturbations in the edge has been previously studied by Zhang et al with the help of antenna code RAPLICASOL (2020, Nucl. Fusion, 60, 096001). The further interesting question is whether the density perturbations have an effect on ion cyclotron resonance heating (ICRH) in the core. In this paper, finite element method based 2D full wave code integrating the core with the edge is used to study this issue. The analytical density perturbations are applied to study the influence of density perturbations on field distribution, power deposition, wave coupling, power partition among different species in the core, and the fraction of energy dissipation in the scrape-off layer. The influence of density perturbations becomes global and significant when the poloidal size of the density blob is comparable to the perpendicular wavelength. In addition, the strength of wave scattering is directly proportional to the amplitude and the radial size of the density blob. Finally, a typical experiment on the EAST is chosen and the influence of realistic density perturbations on ICRH is evaluated.
Shape and interfacial structure of droplets. Exact results and simulations
Authors: Squarcini Alessio , Tinti Antonio
Published: January 2023

We consider the fluctuating interface of a droplet pinned on a flat wall. For such a system we compare results obtained within the exact field theory of phase separation in two dimensions and Monte Carlo (MC) simulations for the Ising model. The interface separating coexisting phases splits and hosts drops whose effect is to produce subleading corrections to the order parameter profile and correlation functions. In this paper we establish the first direct measurement of interface structure effects by means of high-performance MC simulations which successfully confirm the field-theoretical results. Simulations are found to corroborate the theoretical predictions for interface structure effects whose analytical expression has recently been obtained. It is thanks to these higher-order corrections that we are able to correctly resettle a longstanding discrepancy between simulations and theory for the order parameter profile. In addition, our results clearly establish the long-ranged decay of interfacial correlations in the direction parallel to the interface and their spatial confinement within the interfacial region also in the presence of a wall from which the interface is entropically repelled.
Securing text using Rabin-p public key cryptosystem and Spritz algorithm in a hybrid cryptosystem: a tutorial
Authors: Budiman M A , Irvida T A
Published: January 2023

Security in the process of sending digital messages is very important to avoid being theft by unwanted parties. In order to protect the messages, modern cryptography techniques come into play. Public key cryptosystem based on the integer factorization such as Rabin-p could provide high confidentiality as long as the modulus is of a very large integer. On the contrary, having a longer modulus causes two problems: the longer the size of the ciphertext and the longer the time needed for the decryption process. In order to solve this problem, in this research, we combine Rabin-p cryptosystem and Spritz algorithm in a hybrid cryptosystem. Message is encrypted with Spritz algorithm, and the key of Spritz algorithm is then protected by Rabin-p cryptosystem. In this scheme, the encrypted message can be recovered back to the original message while maintaining small decryption time.
Effect of Nickel on the Hydroxide Ion Adsorption of Copper Sulfide: A viewpoint from a first-principle calculation
Authors: Irham M A , Muttaqien F , Bisri S Z , Iskandar F
Published: January 2023

Supercapacitor gains so much interest in recent years due to its capabilities to provide high power densities with high energy density possibilities. Several transition metal sulfides (TMS) give the best capacitance results nowadays, with Copper Sulfides (CuS) promising candidates on supercapacitor electrodes materials. Several approaches have been made to increase TMS-based supercapacitor performance, such as doping, surface functionalization, and nanostructuring. Even though several dopants already reported, other dopants have not yet explored. In this study, we study the nickel effect as dopant on the binding energy of electrolyte in the surface of CuS from first-principles viewpoints. In this study, we limit our investigation of surface interaction with electrolyte only for OH− ions. We prove that the binding energy of electrolyte is increased after introducing dopant in the surface of CuS, which could explain of dopant effect and background proof of future research in this field.
Bamboo marketing management (case study around PT Toba Pulp Lestari concesion)
Authors: Azhar I , Risnasari I , Hemmy A V
Published: January 2023

Bamboo belongs to the gramineae family (grasses), also called Giant Grass, clumps and consists of a number of stems (reeds) that grow gradually, from bamboo shoots to young stems and mature at the age of 4-5 years. And bamboo can be made into many products The purpose of this research is to analyze the marketing strategies of the community around the area of PT. Toba Pulp Lestari. The research method used in this study is descriptive qualitative because it aims to describe the situation on the ground. The results showed that from the analysis of the IFAS, EFAS, and Matrix SWOT shows that bamboo business has opportunities that can be utilized by the community. The strategy (W-O) that must be applied to the research location is to form farmer groups and cooperatives at the village level, provide market information to farmers, improve access/roads to and from villages and improve human resources.
MPU-6050 Wheeled Robot Controlled Hand Gesture Using L298N Driver Based on Arduino
Authors: Azhari  , Nasution T I , Azis P F A
Published: January 2023

Robots are intelligent machines that are controlled by computer applications to perform various operations and services to complete high-risk jobs such as fire, poison, sharp objects, viruses, etc. MPU-6050 Serves as a movement medium in robot electronic systems where the robot moves. Arduino nano functions as a controller on a system robot that includes the MPU-6050, Motor Driver L298N, and NRF24L01. NRF24L01 Serves as a communication medium that is connected between the robot movement system and the hand gesture movement system. The L298N Motor Driver moves according to the signal sent by the MPU-6050 sensor. The L298N Motor Driver functions as an output medium that is made to the DC motor. The L298N Motor Driver will instruct the DC motor to move according to the signal sent by the MPU-6050 module. From the data obtained, the MPU-6050 works at a Y angle with an analog signal of 27.42 ° while driving. The MPU-6050 has X and Y axes with error values at X of 0.32% and Y of 0.48%. NRF24L01 functions as a command to send and receive data signals that work with a maximum range of 30 meters with a speed of 0.457 m/s.
Design and regression analysis of solar tracker through system sun tracker
Authors: Hakim Lukman , Ikhsan Nasution Tulus , Geanita Esi
Published: January 2023

Designing and regression analysis of test result solar tracker has been done. The instrument use Arduino Uno as mikrokontroller, sensor LDR, motor servo, panel surya and LCD as viewer of result test. From result test about arduino uno that show output 1,0,1,0,1 since 5 secon. Testing panel surya show average voltage about 5.84 volt since 5 secon. Testing LCD show 0 for bright condition and 1 for dark condition. Testing motor servo show variation value in 5 steps. Regression Analysis from testing instrument are compare value of voltage from the standart measurer with instrument that design. The source energy that use to instrument is light sun. the data show the value of standar deviasi are (δ) 0,075, so

(

U

A
1

)

=

δ

n

=

0
,
075

20

=
0
,
017

. The equation of regression is (Yreg
) yaitu Yreg
) = a + bx = 0.0096 − 0.0035x. so the value of uncertainty approaching regreesion are UA2 0.013. with value of uncertainty approaching regreesion show the instrument of solar tracker is good work
Study vehicle routing problem using Nearest Neighbor Algorithm
Authors: Ferdiani Harahap Rio , Sawaluddin
Published: January 2023

Vehicle routing problem (VRP) has a key role in logistics management. VRP plays a role in designing the optimal route used by a number of vehicles placed at the depot to serve a number of customers with known requests. To solve the VRP, the nearest neighbor algorithm used to get the most optimal results. The Nearest Neighbor algorithm is a heuristic method which is done by starting the starting point than looking for the nearest point. In this paper, algorithm nearest neighbour can save the distance of 13,14% and cost 13,17%.
Combining Beaufort cipher and RSA-CRT algorithm in a hybrid scheme to secure images
Authors: Rachmawati D , Lubis A N
Published: January 2023

RSA algorithm is one type of algorithms in public-key cryptographic systems where the private keys are kept secret and the public keys can be disseminated. Beaufort Cipher algorithm is a type of classical symmetric algorithm. Meanwhile, the RSA-CRT is one variant of RSA cryptosystem. The RSA-CRT is not efficient for encrypting large files such as image files, since it uses modular exponentiation, which is slow, and the resulting ciphertext would be very much larger than the message. To avoid this problem, a hybrid cryptosystem scheme using RSA-CRT and Beaufort algorithm is designed to encrypt images. Beaufort Cipher algorithm is used for encryption and decryption of digital images, while RSA-CRT algorithm for decryption and decryption of beaufort cipher keys. The results showed that the size of the image (*.BMP) files and the encrypted image files are the same.
Hutchinson model of Holling type II with delay in prey
Authors: Angela Sitinjak Anna , Mawengkang Herman , Ramli Marwan , Tampubolon Rinaldo
Published: January 2023

The problems in daily life can be solved with mathematical models, such as the model of Lotka-Volterra to find out how growth of animals. This model can be modified into the Predator-Prey Model of Hutchinson with delay time and Response Function of Holling type II in which one as active predator and the other as prey, delay time is considered on prey population with assuming that supporting resources of prey are adequate and this type of response function is as interactions between populations of predator and prey. In this paper, linearization and eigenvalues are used to analyze the stability solution of the fixed point so that it can be known the effect of delay time and response function of this type. There are three fixed points are obtained without delay time with two fixed points are stable under certain conditions, but delay time can change the stability of the fixed point.
The sum of hamming distance for some composite graphs relative to vertex-edge incidence matrix
Authors: Ali Safri , Suwilo Saib , Mardiningsih
Published: January 2023

Given C be a vertex-edge incidence matrix of a graph Z. The Hamming distance between two rows C(x, :) and C(y, :) of C is the number of coloumn ℓ such that C (x, ℓ) ≠ C (y, ℓ). In this paper, we discuss the sum of Hamming distances between all pairs of rows of C. We present a formula for the sum of the number of edges and the number of vertices of the graph Z. We then use this formula to determine the sum of Hamming distance for composite graphs such as union of graphs, joint of graphs, corona product of graphs and cartesian product of graphs
Size reduction of the square microstrip patch antenna with Koch fractal for 1.575 GHz applications
Authors: Rambe A H , Angriani T , Fahmi F , Alim S
Published: January 2023

This paper discusses a square patch microstrip antenna with a resonant frequency of 1.575 GHz. The initial design of the antenna was carried out using a theoretical approach and then applied fractal Koch with 1-iteration and 2-iteration. The design optimization is done using the AWR simulator. Based on the optimal design results, the use of Koch fractals has been able to reduce the antenna size. In the first iteration, the antenna size can be reduced by 28% with a minimum return loss value of -33.36 dB at a frequency of 1.575 GHz. In the second iteration, the antenna size can be reduced by 42.4% from the design without fractals with a minimum return loss of -37.18 dB at a frequency of 1.575 GHz. The gain of each antenna design has almost the same value, namely 5.115 dB.
Compressive Strength Study based on Fly Ash Geopolymer Concrete at the age of 28 days under very High Temperature
Authors: Farida F M , Hardjasaputra H , Sofwan A , Surahman A
Published: January 2023

Due to creeping process at the burning material, material’s elastic modulus and yield strength will decrease.Three fire protection system are exist in handling the fire problem: active fire protection, passive fire protection, and safety management. In correlation with material problem due to fire, passive fire protection is a strategy to counter it. This paper presents the results of fire protection by using Suralaya fly ash geopolymer concrete. Three molaritas of geopolymer concrete mixture design are 2M, 4M, and 6 M. Sodium Silicate (Na2SiO3) and Sodium Hydroxide (NaOH) are used as alkaline activator. The results of the experiment were analysed by compressive strength for the optimum values. This study found that the value of compressive strength of steam curing is higher than that of water curing, the value of geopolymer concrete compressive strength of 2M is higher than that of 4M, and the value of geopolymer concrete compressive strength of 6M is higher than that of 4M.
Effect of buffers and pH in antenna sensitized Eu(III) luminescence
Authors: Nielsen Lea Gundorff , Sørensen Thomas Just
Published: January 2023

The photophysics of a europium(III) complex of 1,4,7,10-tetraazacycododecane-1,4,7-triacetic acid-10-(2-methylene)-1-azathioxanthone was investigated in three buffer systems and at three pH values. The buffers—phosphate buffered saline (PBS), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), and universal buffer (UB)—had no effect on the europium luminescence, but a lower overall emission intensity was determined in HEPES. It was found that this was due to quenching of the 1-azathioxanthone first excited singlet state by HEPES. The effect of pH on the photophysics of the complex was found to be minimal, and protonation of the pyridine nitrogen was found to be irrelevant. Even so, pH was shown to change the intensity ratio between 1-azathioxanthone fluorescence and europium luminescence. It was concluded that the full photophysics of a potential molecular probe should be investigated to achieve the best possible results in any application.
Thermal and mechanical characterization of polypropylene/basalt fiber/ethylene propylene diene monomer rubber hybrid composite
Authors: Poornima C , Mallik U S , Suresh R
Published: January 2023

The current study aims in enhancing the impact properties of polypropylene/basalt fiber composite reinforced with different wt% of ethylene propylene diene monomer (EPDM) elastomer to identify the optimum wt% of EPDM at which a balance in strength and toughness can be obtained. According to a dynamic mechanical study, the composite’s viscoelastic behaviour and damping properties improved as the EPDM weight percentage increased in comparison to virgin polypropylene. Scanning and transmission electron microscopy were utilized to see the composite’s fragmented surface. Finally, it was concluded that the presence of a renewable basalt fiber helped in obtaining stability between the strength and toughness of polypropylene-toughened composites. Finally for up to 20 wt% EPDM there was a balance in the composite stiffness and strength.