bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural basis for diamide modulation of ryanodine receptor
Authors: Ma Ruifang , Haji-Ghassemi Omid , Ma Dan , Jiang Heng , Lin Lianyun , Xu Tong , Murayama Takashi , Moussian Bernard , Van Petegem Filip , Yuchi Zhiguang
Published: November 2021

Diamide insecticides target insect ryanodine receptors (RYRs) and cause dysregulation of calcium signaling in insect muscles and neurons, generating worldwide sales over 2 billion US dollars annually. Several resistance mutations have been reported to reduce the efficacy of the diamides, but the exact binding sites and mechanism of resistance mutations were not clear. Recently, we solved the cryo-electron microscopy (cryo-EM) structure of RYR in complex with the anthranilic diamide chlorantraniliprole (CHL). CHL binds to the pseudo–voltage-sensor domain (pVSD) of RYR, a site in proximity to the previously identified resistance mutations. Mutagenesis studies in silico, in mutant cell lines, and in transgenic Drosophila strains revealed the key residues involved in diamide coordination and the molecular mechanism under species-selectivity and resistance mutations. We also proposed that CHL may alleviate the loss-of-function effects of some central core disease (CCD) mutations by increasing the opening probability (Po) of RYR1. In addition, we solved the crystal structures of several RYR domains from the diamondback moth and the bee, revealing insect-specific structural features which could be potentially targeted by novel insecticides. Interestingly, we found that the phosphorylation of insect RYR is temperature dependent, facilitated by the low thermal stability and dynamic structure of the insect RYR. Our structures provide a foundation for developing novel pesticides to overcome the resistance crisis.
Lifetime of autofluorescence: A novel method to determine murine skeletal muscle fiber types
Authors: Manno C. , Tammineni E. , Oropeza Y. , Figueroa L. , Rios E.
Published: November 2021

This work describes a simple way to identify fiber types in living muscles by fluorescence lifetime imaging microscopy (FLIM). We quantified the mean values of lifetimes derived from a two-exponential fit (τ1 and τ2) in freshly dissected mouse FDB and soleus muscles. While τ1 values did not change between muscles, the distribution of τ2 shifted to higher values in FDB. To understand the origin of this difference, we obtained maps of autofluorescence lifetimes in cryosections of both muscles and paired them with immunofluorescence images of myosin heavy chain isoforms (MHC), which allow identification of fiber types. In soleus, τ2 was 3.1 ns for type I (SEM = 0.009, n = 49), 3.4 ns for type IIA (SEM = 0.01, n = 30), and 3.3 ns for type IIX (SEM = 0.01, n = 21). In FDB muscle, τ2 was 3.17 ns for type I (SEM = 0.04, n = 18), 3.5 ns for type IIA (SEM = 0.03, n = 27), and 3.62 ns for type IIX (SEM = 0.03, n = 22). From the distribution of measures, it follows that an FDB fiber with τ2 >3.3 ns is expected to be of type II, and of type I otherwise. This simple classification method has first- and second-class errors estimated at 0.06 and 0.27, respectively. Studies in progress aim at further elucidating the reasons for the different lifetimes, not just among fiber types but between fibers of the same type in the two muscles. Preliminary results point at differences in both the oxidation-reduction and protein-bound versus free states of flavins as causes for the observed divergence of fluorescence lifetimes. Lifetime maps of autofluorescence therefore constitute a tool to identify fiber type that, being practical, fast, and noninvasive, can be applied in living tissue without compromising other experimental interventions.
Species dependent cardiac electrophysiological effects elicited by various potassium channel blocking drugs
Authors: Árpádffy-Lovas Tamás , Naveed Muhammad , Mohammed Aiman Saleh A. , Virág László , Baczkó István , Varró András
Published: November 2021

Rodents are commonly used as models in electrophysiology. However, distinct differences exist between large animals and rodents in terms of their ion channel expression and action potential shapes, possibly limiting the translational value of findings obtained in rodents. We aimed for a direct comparison of the possible impact of selective inhibition of ion channels on the cardiac repolarization in preparations from human hearts and from model species. We applied the standard microelectrode technique at 37°C on cardiac ventricular preparations (papillary muscles and trabecules) from human (n = 63), dog (n = 47), guinea pig (n = 53), rat (n = 43), and rabbit (n = 16) hearts, paced at 1 Hz. To selectively block the IKur current, 1 µM XEN-D101; IK1 current, 10 µM barium chloride; IKr current, 50 nM dofetilide; IKs current, 500 nM HMR-1556; and Ito current, 100 µM chromanol-293B were applied directly to the tissue bath. The block of IKur and IK1 elicited significantly more prominent prolongation of APD in rats (35.6% and 67.9%, respectively) when compared with the other species, including that of human (1.0% and 2.6%, respectively). On the other hand, IKr block did not affect APD in rat preparations (1.6%), whereas it elicited marked prolongation in other species (9.0–47.7%), especially being pronounced in human preparations (60.3%). IKs inhibition elicited similar but minor APD prolongation (0.3–11.4%) in all species. Inhibition of Ito moderately lengthened APD in dog (22.3%) and rabbit (17.5%) preparations but elicited no change of APD in human preparations. In contrast, block of Ito caused marked APD prolongation in rat preparations (33.2%). Our findings suggest that the specific inhibition of various ion channels elicits fundamentally different effects in rodent ventricular action potential when compared with those of other species, including human. Therefore, from a translational standpoint, rodent models in cardiac electrophysiological and arrhythmia research should be used with great caution.
Preconditioning contractions prevent Ca2+-dependent proteolysis of STAC3 and prolonged force depression after eccentric contractions
Authors: Naito Azuma , Ashida Yuki , Himori Koichi , Tamai Katsuyuki , Kimura Iori , Yamada Takashi
Published: November 2021

Preconditioning contractions (PCs) have been shown to markedly improve recovery from force depression after damaging eccentric contractions (ECCs). Here, we examined the mechanism underlying the effects of PCs with special focus on the SH3 and cysteine rich domain 3 (STAC3) that is essential for the transduction of action potential to the Ca2+ release from the sarcoplasmic reticulum. Rat medial gastrocnemius (MG) muscles were removed immediately (REC0), 1 d (REC1), and 4 d (REC4) after exposure to 100 repeated in vivo damaging ECCs. PCs with 10 repeated nondamaging ECCs were applied 2 d before the damaging ECCs. Damaging ECCs induced in vivo isometric torque depression at 50 and 100 Hz stimulation frequencies at REC1 and REC4, which was accompanied by a significant reduction in the amount of STAC3, an activation of calpain 1, and an increased number of Evans Blue dye positive fibers in MG muscles. Importantly, PCs attenuated all these deleterious alterations induced by damaging ECCs. Moreover, mechanistic experiments performed on normal muscle tissue exposed to various concentration of Ca2+ showed a Ca2+-dependent proteolysis of STAC3, which was prevented by calpain inhibitor MDL-28170. In conclusion, PCs improve recovery from force depression after damaging ECCs, presumably by inhibiting the loss of STAC3 due to the increased permeability of cell membrane and subsequent activation of calpain 1.
Possible mechanisms underlying the dynamic assembly of calcium entry units: The role of temperature and pH
Authors: Girolami Barbara , Serano Matteo , Pietrangelo Laura , Protasi Feliciano
Published: November 2021

Skeletal muscle function is regulated by intracellular Ca2+ levels. Two main mechanisms control movements of Ca2+ ions from intracellular stores (i.e., the sarcoplasmic reticulum; SR) and from extracellular space: (1) excitation–contraction (EC) coupling and (2) store-operated Ca2+ entry (SOCE). SOCE allows recovery of extracellular Ca2+ during prolonged muscle activity, when the SR undergoes depletion. We recently discovered that prolonged exercise leads to formation of calcium entry units (CEUs), intracellular junctions located at the I band that are formed by two distinct elements: SR stacks and transverse tubules (TTs). Assembly of CEUs during exercise promotes the interaction between STIM1 and Orai1, the two main proteins that mediate SOCE, and increases muscle resistance to fatigue in the presence of extracellular Ca2+. The molecular mechanisms underlying the exercise-dependent remodeling of SR and TT leading to CEU assembly remain to be fully elucidated. Here, we first verified whether CEUs can assemble ex vivo (in the absence of blood supply and innervation), subjecting excised EDL muscles from mice to an ex vivo incremental fatigue protocol (80 Hz tetanus stimulation lasting 45 min): the data collected demonstrate that CEUs can assemble ex vivo in isolated EDL muscles. We then evaluated if intracellular parameters that are affected by exercise, such as temperature and pH, may influence the assembly of CEUs. We found that higher temperature (36°C versus 25°C) and lower pH (7.2 versus 7.4) promotes formation of CEUs increasing the percentage of fibers containing SR stacks, the number of SR stacks/area, and the elongation of TTs at the I band. Importantly, increased assembly of CEUs at higher temperature (36°C) or at lower pH (7.2) correlated with increased fatigue resistance of EDL muscles in the presence of extracellular Ca2+, suggesting that CEUs assembled ex vivo are functional.
Septin-7 is indispensable in skeletal muscle regeneration
Authors: Telek Andrea , Fodor Janos , Dobrosi Nora , Szabo Laszlo , Gönczi Monika , Dienes Beatrix , Csernoch Laszlo
Published: November 2021

Septins are considered as the fourth component of the cytoskeleton, with septin-7 isoform playing a critical role in myogenic cell division and fusion. Skeletal muscle regeneration is a highly orchestrated process that requires many steps, including proper cell division to achieve functional recovery. Here, the role of septin-7 was investigated in this complex process. To this end, muscle injury was induced in wild type BL6/C57 and septin-7–conditional (mer-Cre-mer) knock-down mice by in vivo BaCl2 injection to the left m. tibialis anterior muscle (TA) of the mice (the right m. tibialis anterior muscle was nontreated control). Mice were sacrificed 4 and 14 d later to reflect the early (monitored by PAX7 level) and late (monitored by myogenin level) phases of muscle regeneration. Western blotting was used to follow the changes of septin-7, PAX7, and myogenin expression at the protein level, while changes of mRNA were detected by qPCR. Morphological differences were visualized by HE staining. Levels of septin-7 protein increased 4 and 14 d after injury in BL6/C57 mice and mRNA expression of SEPT7 showed significant elevation both 4 and 14 d after injection in Cre+ mice only, considered to be a compensatory increase of mRNA expression of SEPT7 in order to ensure the appropriate regeneration process. Furthermore, up-regulation of septin-7 protein was more pronounced on day 14 in both Cre− and Cre+ mice, which may indicate its importance in the later phase of regeneration. Level of PAX7 and myogenin were also increased 4 and 14 d after injury in BL6/C57, Cre−, and Cre+ mice, respectively. Taken together, our data suggest the importance of septin-7 in skeletal muscle regeneration.
Gating of RYR2 channels from the arrhythmic RYR2-P2328S mouse heart and some unexpected actions of flecainide
Authors: Dulhunty Angela F. , Fraser James A. , Huang Christopher L.-H. , Salvage Samantha C.
Published: November 2021

The P2328S mutation in mice is associated with arrhythmia and spontaneous diastolic calcium release in atrial and ventricular myocytes and there is a corresponding leftward shift in the Ca2+-activation curve for mutant RYR2 channels from homozygous mouse hearts (Salvage et al. 2019. J Cell Sci. https://doi.org/10.1242/jcs.229039). P2328 is located in helical domain 1 (HD1) of RYR2. Local structural changes likely result when structurally active proline residues are replaced by structurally inert serine residues. We speculate that local structural changes in HD1 lead to sequential intradomain and interdomain stearic changes through the protein to the distant channel gate, which favor the open pore conformation. The drug flecainide prevents arrhythmia in humans and mouse models of CPVT by blocking NaV1.5 and RYR2 channels. Conventionally, flecainide blocks RYR2 channels in a voltage-dependent manner. We did not observe voltage-dependent pore block. This was possibly because, in contrast to previous studies, the only channel modulators that we used to produce end-diastolic control channel activity were 1 µM cytoplasmic Ca2+ and 1 mM luminal Ca2+. We observed previously unreported, voltage-independent increases in WT and P2328S channel activity at low flecainide concentrations, followed by a decline in activity at higher concentrations. The increase in activity dominated the effect of flecainide on P2328S channels. These effects suggested high-affinity flecainide binding to an activation site and lower-affinity binding to an inhibition site, both distant from the channel pore (Salvage et al. 2021. Cells. https://doi.org/10.3390/cells10082101). Unlike channel block by flecainide, the drug under our conditions stabilized intrinsic sub-conductance activity at +40 mV and −40 mV. Since flecainide effectively reduces CPVT arrythmia clinically and in animal models, we conclude that voltage-independent inhibition and voltage-dependent channel block prevail under cellular conditions. However, channel activation is important to note as it may be unmasked in other circumstances such as acquired cardiac disorders, mutations, or additional drug applications.
Realization of High-Fidelity Controlled-Phase Gates in Extensible Superconducting Qubits Design with a Tunable Coupler
Authors: Ye Yangsen , Cao Sirui , Wu Yulin , Chen Xiawei , Zhu Qingling , Li Shaowei , Chen Fusheng , Gong Ming , Zha Chen , Huang He-Liang , Zhao Youwei , Wang Shiyu , Guo Shaojun , Qian Haoran , Liang Futian , Lin Jin , Xu Yu , Guo Cheng , Sun Lihua , Li Na , Deng Hui , Zhu Xiaobo , Pan Jian-Wei
Published: November 2021

High-fidelity two-qubit gates are essential for the realization of large-scale quantum computation and simulation. Tunable coupler design is used to reduce the problem of parasitic coupling and frequency crowding in many-qubit systems and thus thought to be advantageous. Here we design an extensible 5-qubit system in which center transmon qubit can couple to every four near-neighboring qubits via a capacitive tunable coupler and experimentally demonstrate high-fidelity controlled-phase (CZ) gate by manipulating central qubit and one near-neighboring qubit. Speckle purity benchmarking and cross entropy benchmarking are used to assess the purity fidelity and the fidelity of the CZ gate. The average purity fidelity of the CZ gate is 99.69±0.04% and the average fidelity of the CZ gate is 99.65±0.04%, which means that the control error is about 0.04%. Our work is helpful for resolving many challenges in implementation of large-scale quantum systems.
Observation of the Pinning-Induced Crystal-Hexatic-Glass Transition in Two-Dimensional Colloidal Suspensions
Authors: Sun Xiaoyan , Wang Huaguang , Feng Hao , Zhang Zexin , Ma Yuqiang
Published: November 2021

Identification of the glass formation process in various conditions is of importance for fundamental understanding of the mechanism of glass transitions as well as for developments and applications of glassy materials. We investigate the role of pinning in driving the transformation of crystal into glass in two-dimensional colloidal suspensions of monodisperse microspheres. The pinning is produced by immobilizing a fraction of microspheres on the substrate of sample cells where the mobile microspheres sediment. Structurally, the crystal-hexatic-glass transition occurs with increasing the number fraction of pinning ρ
pinning, and the orientational correlation exhibits a change from quasi-long-range to short-range order at ρ
pinning = 0.02. Interestingly, the dynamics shows a non-monotonic change with increasing the fraction of pinning. This is due to the competition between the disorder that enhances the dynamics and the pinning that hinders the particle motions. Our work highlights the important role of the pinning on the colloidal glass transition, which not only provides a new strategy to prevent crystallization forming glass, but also is helpful for understanding of the vitrification in colloidal systems.
Improved electronic structure prediction of chalcopyrite semiconductors from a semilocal density functional based on Pauli kinetic energy enhancement factor
Authors: Ghosh Arghya , Jana Subrata , Niranjan Manish K , Behera Sushant Kumar , Constantin Lucian A , Samal Prasanjit
Published: November 2021

The correct treatment of d electrons is of prime importance in order to predict the electronic properties of the prototype chalcopyrite semiconductors. The effect of d states is linked with the anion displacement parameter u, which in turn influences the bandgap of these systems. Semilocal exchange–correlation functionals which yield good structural properties of semiconductors and insulators often fail to predict reasonable u because of the underestimation of the bandgaps arising from the strong interplay between d electrons. In the present study, we show that the meta-generalized gradient approximation (meta-GGA) obtained from the cuspless hydrogen density (MGGAC) (2019 Phys. Rev. B 100 155140) performs in an improved manner in apprehending the key features of the electronic properties of chalcopyrites, and its bandgaps are comparative to that obtained using state-of-art hybrid methods. Moreover, the present assessment also shows the importance of the Pauli kinetic energy enhancement factor, α = (τ − τ

W
)/τ
unif in describing the d electrons in chalcopyrites. The present study strongly suggests that the MGGAC functional within semilocal approximations can be a better and preferred choice to study the chalcopyrites and other solid-state systems due to its superior performance and significantly low computational cost.
Large valley polarization in a novel two-dimensional semiconductor H-ZrX2 (X = Cl, Br, I)
Authors: Guo Jiatian , Lu Zhutong , Wang Keyu , Zhao Xiuwen , Hu Guichao , Yuan Xiaobo , Ren Junfeng
Published: November 2021

Inspired by the new progress in the research field of two-dimensional valleytronics materials, we propose a new class of transition metal halides, i.e. H-ZrX2 (X = Cl, Br, I), and investigated their valleytronics properties under the first-principles calculations. It harbors the spin-valley coupling at K and K′ points in the top of valence band, in which the valley spin splitting of ZrI2 can reach up to 115 meV. By carrying out the strain engineering, the valley spin splitting and Berry curvature can be effectively tuned. The long-sought valley polarization reaches up to 108 meV by doping Cr atom, which corresponds to the large Zeeman magnetic field of 778 T. Furthermore, the valley polarization in ZrX2 can be lineally adjusted or flipped by manipulating the magnetization orientation of the doped magnetic atoms. All the results demonstrate the well-founded application prospects of single-layer ZrX2, which can be considered as great candidate for the development of valleytronics and spintronics.
Force measurements near a natural frequency of a measurement system using inverse filters
Authors: Brooks S A , Brooks J D , Green M A
Published: November 2021

Accurate time-resolved force measurements for complex experimental systems are important for minimizing erroneous and misleading data. These measurements become difficult when a natural frequency of the system is in or near the expected frequency domain of the time-varying force being applied. In the cases where it is not possible to avoid this occurrence, the experimenter typically abandons the setup. This work presents an inverse filter method to compensate for the dynamic response of the measurement system. A two degree-of-freedom measurement system is used to obtain force measurements with dominant forcing frequencies above and below the first natural frequency of the system. The results show that inverse filtering can be used along with digital low pass filters to correct amplification and phase shift due to the dynamic response of the measurement system to within ±4.0

%

of total forcing amplitude and ±5.0∘. A simple cam follower mechanism is proposed as a method of low-frequency dynamic testing.
Enhancing the generalizability of predictive models with synergy of data and physics
Authors: Shen Yingjun , Song Zhe , Kusiak Andrew
Published: November 2021

Wind farms require predictive models for predictive maintenance. There is a need to predict values of non-observable parameters beyond ranges reflected in available data. A predictive model developed for one machine many not perform well for another similar machine. This is usually due to a lack of generalizability of data-driven models. To increase the generalizability of predictive models, this research integrates data mining with first-principle knowledge. Physics-based principles are combined with machine learning algorithms through feature engineering, strong rules and divide-and-conquer. The proposed synergy concept is illustrated with a wind turbine blade icing prediction and achieves significant predictive accuracy across different turbines. The proposed process should be widely accepted by wind energy predictive maintenance practitioners because of its simplicity and efficiency. Furthermore, the testing scores of KNN, CART and DNN algorithms are increased by 44.78%, 32.72% and 9.13%, respectively, with our proposed process. We demonstrate the importance of embedding physical principles within the machine learning process, and also highlight an important point that the need for more complex machine learning algorithms in industrial big data mining is often much less than it is in other applications, making it essential to incorporate physics and follow the ‘less is more’ philosophy.
An advanced electrical heating technique for double-sided Y(Gd)BCO coated conductor: gaining high engineering current density based on MOCVD
Authors: Yang Fan , Zhao Ruipeng , Tao Bowan , Chen Xi , Huang Tao , Fei Xi , Chen Tingyu , Xia Tao , Chang Yongtao
Published: November 2021

An advanced electrical heating technique was proposed and adopted for the reel-to-reel deposition of double-sided Gd
x
Y1−x
Ba2Cu3O7−δ
(Y(Gd)BCO) films on the surface of LaMnO3/epitaxial-MgO/IBAD-MgO/Y2O3/Al2O3/Hastelloy tapes based on the metal organic chemical vapor deposition process. In this technique, heating current is introduced into alloy tape to produce heat through the electric brushes. The use of thin Hastelloy tapes is an effective method to obtain a high engineering current density. However, the reduction of the substrate thickness will directly attenuate its mechanical strength, which will lead to the deformation of tapes at high temperature based on original electric heating device. More seriously, the electrical contact between the alloy substrate and the brush will deteriorate, which could cause ignition and ablation at the edge of the tapes. Therefore, in order to improve mechanical and electrical stability, we redesigned a novel electrical heating device to deposit Y(Gd)BCO films. Furthermore, through adopting the multiple-deposition process based on the new electrical heating device, the J
e of Y(Gd)BCO film can reach 900 A mm−2 (at self-field, 77 K), which has been significantly improved compared with the J
e before optimization.
Gaussian information bottleneck and the non-perturbative renormalization group
Authors: Kline Adam G , Palmer Stephanie E
Published: November 2021

The renormalization group (RG) is a class of theoretical techniques used to explain the collective physics of interacting, many-body systems. It has been suggested that the RG formalism may be useful in finding and interpreting emergent low-dimensional structure in complex systems outside of the traditional physics context, such as in biology or computer science. In such contexts, one common dimensionality-reduction framework already in use is information bottleneck (IB), in which the goal is to compress an ‘input’ signal X while maximizing its mutual information with some stochastic ‘relevance’ variable Y. IB has been applied in the vertebrate and invertebrate processing systems to characterize optimal encoding of the future motion of the external world. Other recent work has shown that the RG scheme for the dimer model could be ‘discovered’ by a neural network attempting to solve an IB-like problem. This manuscript explores whether IB and any existing formulation of RG are formally equivalent. A class of soft-cutoff non-perturbative RG techniques are defined by families of non-deterministic coarsening maps, and hence can be formally mapped onto IB, and vice versa. For concreteness, this discussion is limited entirely to Gaussian statistics (GIB), for which IB has exact, closed-form solutions. Under this constraint, GIB has a semigroup structure, in which successive transformations remain IB-optimal. Further, the RG cutoff scheme associated with GIB can be identified. Our results suggest that IB can be used to impose a notion of ‘large scale’ structure, such as biological function, on an RG procedure.
The Optimum Storage Conditions on the Quality of the Stingless bee Honey
Authors: Meechai Imron , Chelong Isma-ae , Chedoloh Romlee
Published: November 2021

Honey of stingless bee has a higher moisture content than bees. Long-term storage may cause fermentation processes to change the physicochemical properties and taste. Thus, the aim of this research was evaluation of the optimum storage condition on the quality of stingless bee honey. Stingless bee honey (Tetragonular larviceps) was contained in plastic bottle and kept at ambient temperature (30-35°C) and low temperature (4-8°C) for 0-45 days. Before and after storage honey were analyzed the physicochemical properties and sensory investigation for comparison of quality. The results showed that temperatures and storage times have affected on the reducing sugar content, pH, conductivity, color, moisture content with significant difference (p<0.05). While, temperatures and storage times have unaffected on the °Brix value (p>0.05). Additionally, the physicochemical properties of honey were according with previously quality report. The sensory investigation indicated that the smell natural flavor, consistency, taste and sourness were not significant difference (p>0.05). In contrast, the color and overall preference were significant difference (p<0.05). For honey quality, Thus, the honey might keep at 4-35°C for ≤45 day of this study.
Porous Activated Carbon Binder-free Scleria sumatrensis Stem-Based for Supercapacitor Application
Authors: Taer Erman , Akbar Tsalis Muhammad Ali , Apriwandi  , Yanti Novi , Awitdrus  , Lazuardi  , Taslim Rika
Published: November 2021

Green, sustainable and effective development technique to obtain high porous activated carbon biomass based is important to boosting supercapacitor performance with environmentally friendly effect as conversion system and energy storage devices. We reported porous activated carbon binder-free Scleria sumatrensis stem-based as electrode material high performance of symmetric supercapacitor. Precursor biomass of Scleria sumatrensis stem was converted into porous carbon through simple ZnCl2 impregnated with different concentration of 0.4M, 0.5M, 0.6M, and 0.7M at high-temperature phyrolysis. All samples confirmed good amorphous carbon with small amounts of oxidative compounds. In two-electrode system, the optimum sample of ACSS0.6 significantly boosting the specific capacitance as high as 142.62 F g−1 at scan rate of 1 mV s−1. Furthermore, the optimum energy density was found to be 19.80 Wh kg−1 at a maximum power density of 71.35 W kg−1 in 1 M H2SO4 aqueous electrolyte. These results confirm that the porous activated carbon binder-free Scleria sumatrensis stem-based through simple ZnCl2 impregnated as an electrode material to boosting the electrochemical behavior of supercapacitors.
Mangifera foetida L. (Macang) Source of Potent Antiviral Activity of Against Dengue Virus Serotype 2 (Anti DENV2)
Authors: Fitmawati  , Safitri Maya , Kholifah S.N. , Emrizal  , Roza Rodesia Mustika
Published: November 2021

The new discovery about the potential ofMangifera foetidaL. as an antiviral will help conservation efforts in nature while maintaining and increasing its biodiversity value. This study aims to characterize the in vitro potential of three varieties ofM. foetidaL. against the dengue virus. Dengue virus is infected in Vero cells, viral replication was measured using the Viral ToxGlo Assay method. The selectivity ability ofMangifera foetidaL. stem bark extract to inhibit the dengue virus was seen from the Selectivity Index (SI) value. The standard curve between the concentration of the compound (μg/mL) and % cell viability was analyzed by linear regression using Microsoft Excel 2010 software. The results showed that the selectivity index (SI) value ofM. foetidaL stem bark extract of Limus, Manis and Batu varieties were 7.58, 6.82 and 16.43, respectively. It was concluded that the extract of Macang stem bark of the Limus, Manis and Batu varieties had the potential to be used as an antiviral for dengue.
Synthesis, in vitro Antioxidant Activity, and Toxicity Evaluation of Hydrazone Derivatives Naphthalene-1-ylmethylene hydrazine
Authors: Jasril  , Juwiyatri E , Fauza S N , Afriana N
Published: November 2021

Hydrazone is a versatile organic compound that has a basic structure (-NHN=CH-) called the azomethine group. This structure is responsible for the physical and chemical of hydrazone, which makes this compound has variety bioactivities such as antioxidant, antitumor, and anticancer. In this work, two hydrazone derivatives from 1-naphthaldehyde and hydrazine (phenylhydrazine/hydrazine hydrate) have been synthesized under microwave irradiation. Their antioxidant activity and toxicity were evaluated by DPPH and BSLT method, respectively. Structures of the synthesized compounds were confirmed based on spectroscopic data included UV, FTIR, HRMS, and 1H-NMR. Based on the DPPH assay, hydrazone from phenylhydrazine has strong antioxidant (IC50 28.90 μg/mL) but inactive antioxidant for hydrazine hydrate (IC50 >1000 μg/mL). However, both compounds have a high toxicity effect on Artemia Salina Leach with each LC50 1.45 and 47.20 μg/mL, hence they have the potential to be developed into anticancer drugs.
Activated Carbons (AC) Prepared by Direct CO2Activation of Parsea Americana seeds Biomass for Supercapacitor Electrodes
Authors: Farma Rakhmawati , Anakis Ramadani Putri , Apriyani Irma
Published: November 2021

Biomass converted into activated carbon (AC) by using physical activation method can form micro-meso pore structure and maintain the interconnected natural pore network of biomass. AC is prepared from the biomass ofParsea Americanaseeds (PAS) through a process of pre-carbonization, chemical activation, carbonization and physical activation which is activated at temperatures of 700°C, 800°C, and 900°C. Characterization of physical properties of AC electrodes consisted of X-ray diffraction, Scanning Electron Microscope-Energy Dispersive X-ray and characterization of electrochemical properties of supercapacitor cells using Cyclic Voltametry. The results showed that the microstructure of the AC electrode has a semicrystalline structure characterized by the presence of two sloping peaks at an angle of 2θ around 24° and 44° which corresponded to the hkl (002) and (100) planes, where the lowest Lc value was produced by the PAS-900 sample. The PAS-900 sample had aggregates or lumps with smaller size in small amounts in the presence of micro-mesopores and had the highest carbon content of 94.50% with the highest capacitance value of 203.12 F/g. The temperature of 900°C is the best activation temperature in the process of manufacture AC electrodes fromParsea Americanaseeds biomass for supercapacitor cell applications.
Of ZnO Nanoparticle using Sandoricum Koetjape Peel Extract as Bio-stabilizer under Microwave Irradiation
Authors: Rini A S , Rati Y , Maisita S W
Published: November 2021

The use of sentul (Sandoricum koetjape) peel extract as a biostabilizer in the synthesis of zinc oxide (ZnO) nanoparticles has been carried out as an environmentally friendly production. This research was conducted by reacting a 0.2 M of Zn precursor (zinc nitrate hexahydrate) solution with Sentul peel extract (10g/l). The samples were varied based on the ratio of the volume of the Zn solution to the Sentul peel extract, i.e., 1:4, 2:3, 1:1, 3:2, and 4:1 where each sample was assigned a ZSk initial code. The ZnO synthesis used a microwave technique with a power of 360 Watt. Morphological, structural, optical absorption, and functional groups were analyzed based on the results of the characterization of SEM, XRD, UV-Vis, and FTIR Spectroscopy. SEM images show the morphology of ZnO particles in the form of semi-hollow spheres and macaron-like shapes. The particle size decreases with the addition of the volume of the Zn solution. The XRD diffraction pattern shows the diffraction peaks that correspond to the hkl plane of the wurtzite hexagonal structure of ZnO. The highest optical absorption of the UV-Vis spectrum occurred in the wavelength range of 300-360 nm. The FTIR spectrum represents the involvement of the O-H functional groups derived from the polyphenolic compound of sentul peel extract.
Modeling of Clavulanic Acid Production from Streptomyces clavuligerus using a Continuous Operation Mode
Authors: Ariza L , Rubio J , Moreno V , Niño L , Gelves G
Published: November 2021

Clavulanic acid is a β-lactam inhibitor produced by fermentation with Streptomyces clavuligerus cells, and it is usually used to prevent resistance to certain antibiotics. However, CA production is limited at the bioreactor level due to its low performance. The latter generates expensive processes and challenging to operate on a large scale. In this research, a mathematical model is proposed to simulate the clavulanic acid production from an operation strategy based on continuous mode. The preceding, to identify trends allowing to improve the productivity of the mentioned metabolite. Results are compared to the traditional operating batch mode. According to the results found, the final concentration of the β-lactam inhibitor could be increased by up to 60% regarding the simulated data in batch mode. Results obtained demonstrate the importance of computational techniques in bioprocess engineering since bioprocess simulation focuses on identifying critical operating parameters as a starting point in antibiotic production optimization.
Modelling of DHA Production from S. Limacinum ouc88: fed-batch perspectives
Authors: Contreras B , Basto D , Gelves G
Published: November 2021

Biotechnology and its need to improve industrial processes have shown the need for techniques that allow processes optimization. Computer simulation offers the advantage of determining production prospects without significant resources and experimentation time. That is why a kinetic study of DHA (docosahexaenoic acid) production from Schizochytrium limacinum OUC88 was developed in this investigation. Based on the above, a mathematical approach to simulate DHA production in a fed-batch model is proposed in this work, using Matlab software. The experimental data for determining kinetic parameters were taken from previous investigations, and a simulated DHA level in the fed-batch mode of 150 g/L was reached. On the contrary, the simulated results in batch mode present only a maximum value of 30 g/L, demonstrating the effectiveness of the fed-batch implementation with perspectives on improving processes.
Computer-Aided Evaluation of Ethanol Production from a Continuous Operating Mode using Simulink
Authors: Alvarado K , Niño L , Gelves G
Published: November 2021

Fossil fuels have become a great energy source worldwide. However, its prolonged use has caused severe environmental pollution problems. Biofuels generated from biomass as a product of microbial biotechnology emerge as an alternative to the use of compounds derived from oil. Therefore, their production results in complex experiments and source investment. That is why engineering studies implementation using mathematical models and simulation techniques should be specified in bioprocesses. The latter focused on optimizing the process parameters, maximizing productivity, generating greater profitability, and reducing cost. This research aimed at the computer-assisted evaluation of obtaining bioethanol from Saccharomyces cerevisiae to determine the most critical factors in the production process using a continuous mode. It was determined that the feed rate significantly influences the bioethanol volumetric productivity.
Solution of the Schrödinger torsion equation in the basis set of Mathieu functions: verification by numerical experiment
Authors: Belov A N , Turovtsev V V , Fedina Yu A , Orlov Yu D
Published: November 2021

The efficiency of the algorithm for the numerical solution of the Schrödinger torsion equation in the basis of Mathieu functions has been considered. The computational stability of the proposed algorithm is shown. The energies of torsion transitions determined in the basis sets of plane waves and Mathieu functions have been compared with the results of spectroscopy. A conclusion about the applicability of the algorithm using the basis set of Mathieu functions to the solution of the Schrödinger equation with a periodic potential has been derived.
Distribution of thermophysical and mechanical properties of titanium nickelide in the welding zone
Authors: Burkhovetskiy V V , Kamaev A O , Kiselev A Yu , Kurushkin D V , Khanaev V M , Khlopkov E A , Chernyavskaya N V , Shkuratov B E , Ostropiko E S , Vyunenko Yu N
Published: November 2021

The paper analyzes the behavior of the deformation characteristics of welded joints made of TiNi alloy with a shape memory effect. Comparison of the level of tensile strength of welded samples made by the TIG method in an Ar and He atmosphere was carried out using a Instron 5985 universal machine. The study of the material structure in the weld zone and the heat-affected zone was carried out on longitudinal sections using a JSM-6490LV electron microscope. To estimate the mechanical parameters PMT-3 microhardness tester was used. The calorimetric parameters of the welded samples were obtained using a differential scanning calorimeters METTLER TOLEDO 822e and TA Instruments Q20. To analyze the gradient properties at the weld zone and the heat-affected zone, the temperature fields were calculated using the thermal conductivity equation included in the model of the residual stress mechanism.
Symmetric 2-adic complexity of generalized cyclotomic sequences of order six with period p
n
Authors: Edemskiy V A , Koltsova S A
Published: November 2021

In this paper, the symmetric 2-adic complexity of generalized cyclotomic sequences of order six with period equals a power of an odd prime is studied. The estimate of symmetric 2-adic complexity of these sequences is obtained. It is shown that above sequences have high symmetric 2-adic complexity and the 2-adic complexity of this class of sequences is large enough to resist the attack of the rational approximation algorithm for feedback with carry shift registers.
Mathematical model for determining characteristic points on the radial knife of the geokhod executive body
Authors: Efremenkov A B , Aksenov V V , Sadovets V Yu , Preis E V , Pashkov D A
Published: November 2021

The article presents a mathematical model for determining the values of the characteristic points of the knife executive body (EB) of the geokhod. For this, the boundary conditions for determining the characteristic points on the radial knife of the geokhod executive body are indicated. The result of the work are the obtained expressions for determining: P

a.c
is the the projection of the component of the soil cutting force, depending on the cutting width, onto the main axis of rotation of the geokhod, R

e.a.c
is the projection of the component of the cutting force of the soil on the plane, which is located perpendicular to the main axis of rotation of the geokhod. Based on the work carried out, tasks for further research were identified.
Dependency of regret on accuracy of variance estimation for different versions of UCB strategy for Gaussian multi-armed bandits
Authors: Garbar S V
Published: November 2021

We consider two variations of upper confidence bound strategy for Gaussian two-armed bandits. Rewards for the arms are assumed to have unknown expected values and unknown variances. It is demonstrated that expected regret values for both discussed strategies are continuous functions of reward variance. A set of Monte-Carlo simulations was performed to show the nature of the relation between variance estimation and losses. It is shown that the regret grows only slightly when the estimation error is fairly large, which allows to estimate the variance during the initial steps of the control and stop this estimation later.
Thermodynamics and phase diagram calculation of the binary arsenic-tellurium system in the framework of the generalized lattice model
Authors: Gerasimov N V , Zakharov M A
Published: November 2021

In this work we describe how to efficiently calculate thermodynamic properties and T-x diagram of binary As-Te solution in the generalized lattice model. All the thermodynamic parameters of the As-Te solution are obtained within framework of the generalized lattice model. The binary phase diagram of As-Te system is calculated and good agreement with experimental data is obtained.
Digital technologies used in technical diagnostics, assessment of technical condition, maintenance and repair of mining machines and equipment
Authors: Gericke B L , Sushko A E , Gericke P B , Efremenkov A B
Published: November 2021

The article deals with the organization of a single technological space for technical diagnostics, maintenance, and repair of mining equipment. The digital technology that unites all services related to production, diagnostics of technical condition, maintenance and repair of mining equipment is based on the SAFE PLANT software package, which provides globality, scalability, versatility, integrability, modularity, distribution, and functionality. The article reflects the results of the implementation of the system at an industrial enterprise.
Thermodynamics as a consequence of mechanics
Authors: Granovskii Ya I
Published: November 2021

In this paper the transition from the microscopic description to macroscopic one is considered. Transformation of Mechanics into Thermodynamics follows as its consequence. Retardation of interactions and their role in irreversibility of both theories are analyzed. The mechanical analogue of entropy is found.
Mathematical description of the processes of synthesis of digital multispectral images
Authors: Kalitov M A , Kornyshev N P
Published: November 2021

The article discusses the features of the formation of digital multispectral images corresponding to narrow registration zones. The processes of signal transformations are analyzed during the synthesis of such images from the original multispectral images with overlapping spectral flux registration zones. Questions of the mathematical description of the differential and multiplicative method for the synthesis of spectrozonal images are discussed. Analytical expressions are given that correspond to signal transformations of the original digital multispectral images in their differential and multiplicative synthesis.
Mathematical model for determining the forces of interaction of geokhod systems with geo-environment and with each other
Authors: Khoreshok A A , Pashkov D A , Efremenkov A B
Published: November 2021

The article gives an example of constructing a generalized mathematical model of the interaction processes occurring in geokhod mining. An example of the solution of a particular problem is given, the determination of the values of the forces arising from the interaction of the blade of an external mover with geoenvironment.
Universal strategies for the two-alternative big data processing
Authors: Kolnogorov A V
Published: November 2021

We consider the two-alternative processing of big data in the framework of the two-armed bandit problem. We assume that there are two processing methods with different, fixed but a priori unknown efficiencies which are due to different reasons including those caused by legislation. Results of data processing are interpreted as random incomes. During control process, one has to determine the most efficient method and to provide its primary usage. The difficulty of the problem is caused by the fact that its solution essentially depends on distributions of one-step incomes corresponding to results of data processing. However, in case of big data we show that there are universal processing strategies for a wide class of distributions of one-step incomes. To this end, we consider Gaussian two-armed bandit which naturally arises when batch data processing is analyzed. Minimax risk and minimax strategy are searched for as Bayesian ones corresponding to the worst-case prior distribution. We present recursive integro-difference equation for computing Bayesian risk and Bayesian strategy with respect to the worst-case prior distribution and a second order partial differential equation into which integro-difference equation turns in the limiting case as the control horizon goes to infinity. We also show that, in case of big data, processing of data one-by-one is not more efficient than optimal batch data processing for some types of distributions of one-step incomes, e.g. for Bernoulli and Poissonian distributions. Numerical experiments are presented and show that proposed universal strategies provide high performance of two-alternative big data processing.
Microprocesses at the brass surface after impact of scanning beam of pulse-frequency ultraviolet nanosecond laser
Authors: Malinskiy T , Mikolutskiy S , Rogalin V , Khomich Yu , Zheleznov V , Kaplunov I , Ivanova A
Published: November 2021

A mode of laser heat treatment of the brass surface prior to conducting of diffusion bonding is proposed. We used the frequency-pulse radiation of a nanosecond ultraviolet laser at a pulse energy density W = 0.15 - 0.52 J/cm2. The metal sample was moved relative to a stationary laser beam along a raster trajectory (“snake”) so that adjacent spots were overlapped with an overlap ratio of ⩾ 99 %. The impact of radiation on brass was carried out in a subthreshold mode excluding crater formation. The process took place while the metal remained in a condensed state. A regular rough structure with a height of individual uplifts of the order of 1 micron was formed on the surface of the brass. article is devoted to creation of aerosolized detergent compositions, needful for use during operation of high-precision metal mirrors, as a rule, in field conditions. The created detergent compositions with inhibitory properties allow, simultaneously with carrying out the process of physicochemical cleaning of optical surface from technological impurities, to ensure its protection from the influence of adverse climatic factors during storage, transportation, installation and exploitation of the element with the possibility of its alignment. The high climatic resilience of the protective films investigated in this article, which are formed during the cleaning of the optical surface, is shown. In this case, the optical characteristics of the processed elements after climatic tests do not get worse.