Search

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Charging the LiCoO2 (LCO) cathode to a higher voltage, for example 4.5 V compared to the commonly used 4.2 V, is now intensively pursued so as to achieve a higher specific capacity. However, it suffers severe surface structural degradation and detrimental interfacial side reactions between cathode and electrolyte, which lead to the fast capacity fading during long-term cycling. Here, a surface coating strategy was developed for the protection of 4.5 V LCO by constructing a manganese oxides (MOs) nanoshell around LCO particles, which was achieved through a solution-based coating process with success in controlling the growth kinetics of the coating species. We found that the introduction of the MOs nanoshell is highly effective in alleviating the organic electrolyte decomposition at the cathode surface, thus ensuring a much more stable LiF-rich cathode-electrolyte interface and an obvious lower interfacial resistance during electrochemical cycling. Meanwhile, this protection layer can effectively improve the structural stability of the cathode by hindering the cracks formation and structural degradation of LCO particles. Therefore, the MOs modified LCO exhibited excellent rate performance and a high discharge capacity retention of 81.5% after 100 cycles at 1 C compared with the untreated LCO (55.2%), as well as the improved thermal stability and cyclability at the elevated temperature. It is expected that this discovery and fundamental understanding of the surface chemistry regulation strategy provide promising insights into improving the reversibility and stability of LCO cathode at the cut-off voltage of 4.5 V. [ABSTRACT FROM AUTHOR]

Purpose: A substantial need for effective and safe treatment options is still unmet for patients with heavily pre-treated human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). Herein, we assessed the efficacy and safety of pyrotinib plus trastuzumab and chemotherapy in patients with heavily treated HER2-positive MBC. Methods: In this single-arm exploratory phase II trial, patients with HER2-positive MBC previously treated with trastuzumab plus lapatinib or pertuzumab, received pyrotinib plus trastuzumab and chemotherapy. The primary end point was progression-free survival (PFS) in the total population (TP). Secondary end points included PFS in the subgroup with brain metastases (Sub-BrM), confirmed objective response rate (ORR), clinical benefit rate (CBR), disease control rate (DCR), exploration of predictive factors of PFS, and safety. Results: Between November 1, 2018, and March 31, 2021, 40 patients were eligible for this study. The median PFS reached 7.5 months (95% confidence interval [CI] 4.7 to 9.9 months) and 9.4 months (95% CI 6.6 to 12.1 months) in the TP and Sub-BrM, respectively. ORR was 50.5% (20/40). CBR was 75.5% (30/40) and DCR reached 97.5% (39/40). Cox univariate and multivariate analyses demonstrated that liver or/and lung metastases was the significant adverse prognostic factor for PFS (p = 0.018; p = 0.026; respectively). The most frequent grade 3 or 4 treatment-related adverse events were diarrhea, neutropenia and leukopenia. No new safety signals were observed. Conclusion: Pyrotinib plus trastuzumab and chemotherapy offered a promising option with manageable safety profile for heavily pre-treated HER2-positive MBC, especially for those without liver or/and lung metastases. [ABSTRACT FROM AUTHOR]

This paper explores the impact of sovereign defaults on lending countries and evaluates government intervention policies in a dynamic infinite-horizon model. When banks in the lending country hold risky foreign bonds, the default risk in the foreign country has a spillover effect on the output volatility of the lending country. A macroprudential tax on the purchase of foreign bonds reduces the lending country's exposure to foreign sovereign risk and output volatility. Households gain in welfare as a result, but bankers lose because taxes lower banks' profitability. The effect on overall welfare is mixed, depending on which group dominates. It is beneficial ex post to implement bailout policies when the government redistributes resources from households to banks after default, but bailouts encourage banks to take on risk by holding more sovereign bonds ex ante, leading to greater output fluctuations in the lending country. [ABSTRACT FROM AUTHOR]

This paper proposes a modified two-dimensional (2-D) shear-lag model considering unidirectional or bidirectional interfacial damage to analyze the stress transfer mechanism of rectangular patch-reinforced composites under tensile load. The semi-analytical solutions for bidirectional normal stresses and interfacial shear stresses are provided, accounting for interfacial orthotropic anisotropy and the stiffness variation in the damage stage. The study examines the influence of material parameters, including the difference in Poisson's ratios between the substrate and patch, thickness ratio, and aspect ratio, on interfacial damage in composite materials. The results show a good agreement between the stress distribution solutions predicted by the proposed 2-D model and finite element results. The model provides an effective solution to the 2-D stress problem in rectangular patch-reinforced composites with interface damage. [ABSTRACT FROM AUTHOR]

Objective: To produce high concentrations of hyperoside from quercetin using recombinant Escherichia coli with in situ regeneration of UDP-galactose. Results: Sucrose synthase from Glycine max (GmSUS) was co-expressed with UDP-glucose epimerase from E. coli (GalE) in E. coli for regenerating UDP-galactose from UDP and sucrose. Glycosyltransferase from Petunia hybrida (PhUGT) was introduced to synthesize hyperoside from quercetin through the regeneration system of UDP-galactose. Co-expressing with molecular chaperones GroEL/ES successfully enhanced the catalytic efficiency of the recombinant strain, which assisted the soluble expression of PhUGT. By using a fed-batch approach, the production of hyperoside reached 863.7 mg L−1 with a corresponding molar conversion of 93.6% and a specific productivity of 72.5 mg L−1 h−1. Conclusion: The method described herein for hyperoside production can be widely applied for the synthesis of isorhamnetin-3-O-galactoside, kaempferol-3-O-galactoside and other flavonoids. [ABSTRACT FROM AUTHOR]

Objective: To enhance biotin production in Escherichia coli by engineering a heterologous biotin synthetic pathway. Results: Biotin operon genes from Pseudomonas putida, which consisted of a bioBFHCD cluster and a bioA gene, was engineered into Escherichia coli for biotin production. The introduction of bioW gene from Bacillus subtilis, encoding pimeloyl-CoA synthetase and sam2 gene from Saccharomyces cerevisiae, encoding S-adenosyl-L-methionine (SAM) synthetase contributed to the heterologous production of biotin in recombinant E. coli. Furthermore, biotin production was efficiently enhanced by optimization of the fermentation compositions, especially pimelic acid and L-methionine, the precursor related to the pimeloyl-CoA and SAM synthesis, respectively. The combination of overexpression of the heterologous biotin operon genes and enhanced supply of key intermediate pimeloyl-CoA and SAM increased biotin production in E. coli by more than 121-fold. With bioprocess engineering efforts, biotin was produced at a final titer of 92.6 mg/L in a shake flask and 208.7 mg/L in a fed-batch fermenter. Conclusion: Through introduction of heterologous biotin synthetic pathway, increasing the supply of precursor pimeloyl-CoA and cofactor SAM can significantly enhance biotin production in E. coli. [ABSTRACT FROM AUTHOR]

Traditional denoising methods based on fixed transforms are not suited for exploiting their complicated characteristics and attenuating noise due to their lack of adaptability. Recently, a novel method called morphological component analysis (MCA) was proposed to separate different geometrical components by amalgamating several irrelevance transforms. For studying the local singular and smooth linear components characteristics of seismic data, we propose a novel method that excels particularly in attenuating random and coherent noise while preserving effective signals. The proposed method, which combines MCA, dictionary learning (DL), and deep noise reduction consists of three steps: first, we separate the local singular and smooth linear components from the seismic signal using MCA. Second, we apply a DL method on these two components to suppress noise and obtain the denoised signal and noise. In the final step, we apply the DL method to the noise to obtain a little of the seismic signal. Afterwards, we integrate the two seismic signals to obtain the final denoised seismic signal. Numerical results indicate that the proposed method can effectively suppress the undesired noise, maximally preserve the information of geologic bodies and structures, and improve the signal-to-noise ratio (S/N) of the data. We also demonstrate the superior performance of this approach by comparing with other novel dictionaries such as discrete cosine transforms (DCTs), undecimated discrete wavelet transforms (UDWTs), or curvelet transforms. This algorithm provides new ideas for data processing to advance quality and S/N of seismic data. [ABSTRACT FROM AUTHOR]

Porous silicon (Si) nanostructures have aroused much interest as lithium-ion battery anodes because of the large space to accommodate the volume change in lithiation and delithiation and shorter ion transfer distance. However, fabrication of porous structures tends to be difficult to control and complex, so, the final electrochemical performance can be compromised. Herein, a modest magnesiothermic reduction (MMR) reaction is demonstrated to produce blackberry-like porous Si nanospheres (PSSs) controllably using magnesium silicide (Mg2Si) as Mg source and SiO2 nanospheres as the reactant. This improved MR method provides good control of the kinetics and heat release compared to the traditional MR (TMR) method using Mg powder as the reactant. The PSSs obtained by MMR reaction has higher structural integrity than that fabricated by TMR. After encapsulation with reduced graphene oxide, the Si/C composite exhibits superior cycling stability and rates such as a high reversible capacity of 1034 mAh·g−1 at 0.5C (4200 mAh·g−1 at 1.0C) after 1000 cycles, capacity retention of 79.5%, and high rate capacity of 497 mAh·g−1 at 2.0C. This strategy offers a new route to fabricate high-performance porous Si anodes and can be extended to other materials such as germanium. [ABSTRACT FROM AUTHOR]

Objective: To investigate the shared mechanisms of scutellarin in angina pectoris (AP) and ischemic stroke (IS) treatment. Methods: A network pharmacology approach was used to detect the potential mechanisms of scutellarin in AP and IS treatment by target prediction, protein-protein interaction (PPI) data collection, network construction, network analysis, and enrichment analysis. Furthermore, molecular docking simulation was employed to analyze the interaction between scutellarin and core targets. Results: Two networks were established, including a disease-target network and a PPI network of scutellarin targets against AP and IS. Network analysis showed that 14 targets, namely, AKT1, VEGFA, JUN, ALB, MTOR, ESR1, MAPK8, HSP90AA1, NOS3, SERPINE1, FGA, F2, FOXO3, and STAT1, might be the therapeutic targets of scutellarin in AP and IS. Among them, NOS3 and F2 were recognized as the core targets. Additionally, molecular docking simulation confifirmed that scutellarin exhibited a relatively high potential for binding to the active sites of NOS3 and F2. Furthermore, enrichment analysis indicated that scutellarin might exert a therapeutic role in both AP and IS by regulating several important pathways, such as coagulation cascades, mitogen-activated protein kinase (MAPK) signaling pathway, phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway, Toll-like receptor signaling pathway, hypoxia inducible factor-1 (HIF-1) signaling pathway, forkhead box O (FoxO) signaling pathway, tumor necrosis factor (TNF) signaling pathway, adipocytokine signaling pathway, insulin signaling pathway, insulin resistance, and estrogen signaling pathway. Conclusions: The shared underlying mechanisms of scutellarin on AP and IS treatment might be strongly associated with its vasorelaxant, anticoagulant, anti-inflammatory, and antioxidative effects as well as its effect on improving lipid metabolism. [ABSTRACT FROM AUTHOR]

In this study, a new adaptive morphological filter is developed based on the mathematical morphology algorithm and characteristics of the subtle differences in the waveform morphology in seismic data. The algorithm improves the traditional morphological dilation and corrosion operations. In this study, we propose a multiscale adaptive operator based on the principle of morphological structural "probes" and present the corresponding mathematical proof. Simulation experiments and actual seismic data processing results show that compared with traditional morphological filters, the constructed OCCO-based multistructure adaptive morphological filter can suppress noise to the greatest extent. Moreover, it can effectively improve the SNR of the images, and offers great application prospects. [ABSTRACT FROM AUTHOR]

Medicinal plants have been studied for potential endophytic interactions and numerous studies have provided evidence that seeds harbor diverse microbial communities, not only on their surfaces but also within the embryo. Adenosine deaminase (ADA) is known as a potential therapeutic target for the treatment of lymphoproliferative disorders and cancer. Therefore, in this study, 20 types of medicinal plant seeds were used to screen endophytic fungi with tissue homogenate and streak. In addition, 128 morphologically distinct endophyte strains were isolated and their ADA inhibitory activity determined by a spectrophotometric assay. The strain with the highest inhibitory activity was identified as Cochliobolus sp. Seven compounds were isolated from the strain using a chromatography method. Compound 3 showed the highest ADA inhibitory activity and was identified as 5-hydroxy-2-hydroxymethyl-4H-pyran-4-one, based on the results of 1H and 13C NMR spectroscopy. The results of molecular docking suggested that compound 3 binds to the active site and the nonspecific binding site of the ADA. Furthermore, we found that compound 3 is a mixed ADA inhibitor. These results indicate that endophytic strains are a promising source of ADA inhibitors and that compound 3 may be a superior source for use in the preparation of biologically active ADA inhibitor compounds used to treat cancer. [ABSTRACT FROM AUTHOR]

This study employed a data envelopment analysis (DEA) by using slacks-based measure (SBM) with undesirable outputs to assess the industrial environmental efficiency of western China during the period of 2001–2015. The Malmquist index was further used to examine the changes in the industrial environmental efficiency of the analyzed region. The result showed that western China presented a low industrial environmental efficiency throughout the period of 2001–2015. Chongqing City was the only province that exhibited strong economic and environmental coordination. The level of technical development was identified as a key determinant of industrial environmental efficiency. This study provided policy implications on emissions reduction and the improvement of industrial efficiency. Limitations of the approach were provided to lay foundation for future studies. [ABSTRACT FROM AUTHOR]

Objective: To strengthen NADH regeneration in the biosynthesis of L-2-aminobutyric acid (L-ABA).Results: L-Threonine deaminase (L-TD) from Escherichia coli K12 was modified by directed evolution and rational design to improve its endurance to heat treatment. The half-life of mutant G323D/F510L/T344A at 42 °C increased from 10 to 210 min, a 20-fold increase compared to the wild-type L-TD, and the temperature at which the activity of the enzyme decreased by 50% in 15 min increased from 39 to 53 °C. The mutant together with thermostable L-leucine dehydrogenase from Bacillus sphaericus DSM730 and formate dehydrogenase from Candida boidinii constituted a one-pot system for L-ABA biosynthesis. Employing preheat treatment in the one-pot system, the biosynthesis of L-ABA and total turnover number of NAD+/NADH were 0.993 M and 16,469, in contrast to 0.635 M and 10,531 with wild-type L-TD, respectively.Conclusions: By using the engineered L-TD during endured preheat treatment, the one-pot system has achieved a higher productivity of L-ABA and total turnover number of coenzyme. [ABSTRACT FROM AUTHOR]

The attenuation factor or quality factor (Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a method to calculate the Q-factor based on the prestack Q-factor inversion and the generalized S-transform. The proposed method specifies a standard primary wavelet and calculates the cumulative Q-factors; then, it finds the interlaminar Q-factors using the relation between Q and offset (QVO) and the Dix formula. The proposed method is alternative to methods that calculate interlaminar Q-factors after horizon picking. Because the frequency spectrum of each horizon can be extracted continuously on a 2D time-frequency spectrum, the method is called the continuous spectral ratio slope (CSRS) method. Compared with the other Q-inversion methods, the method offers nearly effortless computations and stability, and has mathematical and physical significance. We use numerical modeling to verify the feasibility of the method and apply it to real data from an oilfield in Ahdeb, Iraq. The results suggest that the resolution and spatial stability of the Q-profile are optimal and contain abundant interlaminar information that is extremely helpful in making lithology and fluid predictions. [ABSTRACT FROM AUTHOR]

Purpose: We present a systematic review of the recent literatures regarding the arthroscopic and open technique in fragment fixation for osteochondritis dissecans (OCD) of the humeral capitellum and an analysis of the subjective and objective outcomes between these two procedures.Methods: PubMed and EMBASE were reviewed for suitable articles relating to fragment fixation for OCD, both open and arthroscopic. We included all studies reporting on the clinical outcomes of these two procedures that were published in the English language. Data extracted from each study included level of evidence, number of patients, surgical techniques, length of follow-up, clinical outcome measures including outcome scores, range of motion (ROM), return to sports, osseous union and complications. We analyzed each study to determine the primary outcome measurement.Results: A total of ten studies met our inclusion criteria. Among all studies, 35 arthroscopic procedures and 107 open procedures were performed. After the procedure, 70 patients (86.4%) in the open group returned to their sports, and 32 patients (91.4%) in the arthroscopic group returned to their sports. In the arthroscopic group, patients gained 14.1 degrees of flexion and 9.5 degrees of extension after surgery. In the open group, patients gained 8 degrees of flexion and 5.7 degrees of extension. Five patients (4.7%) had complications in the open group. No complication was found in the arthroscopic group.Conclusions: Both open and arthroscopic lesion debridement with fragment fixation are successful in treating unstable OCD. The arthroscopic technique may be a better choice than the open procedure, but we need high-level evidence to determine the superiority of the open or arthroscopic techniques in treating elbow OCD.Level Of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Ischemic strokes occur as a result of an obstruction within a blood vessel supplying blood to the brain and accounts for about 87 % of all cases. During the cerebral ischemia, most of the neurons undergo the necrosis and apoptosis upon the exposure to the dramatic blood flow reduction. Although, it is known that both the intrinsic and extrinsic pathways are involved in the neuronal apoptosis of ischemic brain injury. The complex underlying mechanisms remains less known. MicroRNAs are a class of endogenous small non-coding RNAs and the role of miRNAs in the pathophysiology of stroke has been studied. In this study, we found that miR-9 is downregulated in the mice with middle cerebral artery occlusion (MCAO) brain and oxygen-glucose deprivation (OGD) neurons. Application of miR-9 gamer could restore the neurological scores and reduces the infarct volume, brain water content, and the behavioral impairments. Moreover, upregulation of miR-9 suppresses the neuronal apoptosis in MCAO brain and OGD neurons. Furthermore, we identified that Bcl2l11 as the direct target of miR-9 and manipulation of miR-9 induces the corresponding changing of Bcl2l11 protein level. Finally, we found that the protein level of Bcl2l11 is increased in the MCAO brain and OGD neurons. Our study demonstrated the critical role of miR-9 in the neuronal apoptosis of ischemic brain injury. [ABSTRACT FROM AUTHOR]

Aging is a natural process accompanied with many disorders, including the memory decline. The underlying mechanisms for the age-related memory decline are complicated. Previous work suggested that oxidative stress, inflammatory disturbance, and the neurotropic absence play important roles in the age-related disorders. Thus, to seek a drug to target those abnormalities might be a possible protective approach for aging. Here, we reported that supplements with exogenous erythropoietin (EPO) for 4 weeks could partially rescue the spatial and fear memory impairments in aged rats. The EPO treatment also suppresses the oxidative stress and inflammatory response. Most importantly, EPO supplement restores the mRNA and protein levels of brain-derived neurotrophic factor (BDNF), the critical neurotropic factor for synaptic plasticity and memory. Our study strongly suggests the potential usage of EPO in an anti-aging agent clinically. [ABSTRACT FROM AUTHOR]

Malignant astrocytomas are the most common primary brain tumors. The critical characterizes of astrocyomas are their aggressive and infiltrative in the brain, which leads to uncontrollable by conventional forms of therapy. MicroRNAs are small RNAs that had been found to regulate their targets by specific binding to the 3′-untranslated region (3′UTR) of mRNA. Recent advances in understanding the molecular biology of these tumors have revealed that microRNA (miRNA) disruption may play important roles in the pathogenesis of astrocytomas. And some of the miRNA alterations were found in the serum of astrocytoma patients. In this study, we studied the expression profile of miR-128, in the different stages of astrocytoma tissues and two human astrocytoma cell lines, A172 and T98G cells. We found that the levels of miR-128 are decreased in the A172 and T98G cells when compared to normal human astrocyte (NHA). Furthermore, the levels of miR-128 decreased gradually to the pathological stages of astrocytomas. We also identified that TROVE2 is a novel target of miR-128 by the luciferase reporter system. Furthermore, the expression levels of TROVE2 are dramatically increased with the pathological stages increasing. Finally, the levels of TROVE2 are negatively correlated with miR-128 in astrocytoma tissues. Our data provided novel evidence for the miR-128 and TROVE2 in the development of human astrocytomas. [ABSTRACT FROM AUTHOR]

A simple and effective polymer fluorescent thermosensitive system was successfully developed based on the synergistic effect of excimer/monomer interconversion of pyrene derivatives and electrostatic interaction between polyelectrolyte and charged fluorophore. As for the system, the excimer-monomer conversion, thermosensitive behavior and thermo-responsive reversibility were investigated experimentally. Temperature variation and temperature-distribution induced fluorescence changes can be observed directly by naked eyes. Thus, this polymer system holds promise for serving as a fluorescent thermometer. [ABSTRACT FROM AUTHOR]

Background: It was reported that the nuclear receptor coactivator amplified in breast cancer1 (AIB1) could regulate cancer cell invasion and migration in a nuclear receptor signaling-independent manner. Meanwhile, the process of epithelial mesenchymal transition (EMT) is critical for tumor invasion and metastasis. The present study aimed to determine the role of AIB1 and EMT markers in human pancreatic adenocarcinoma. Methods: AIB1, ZO-1, E-cadherin, vimentin, and N-cadherin protein expression in 76 pancreatic adenocarcinomas were assessed using immunohistochemistry and analyzed for clinicopathological significance. Results: The frequency of AIB1 overexpression in pancreatic adenocarcinomas with lymph node metastasis is 68 % (19/28), which is significantly higher than in pancreatic adenocarcinomas without lymph node metastasis (42 %; 20/48). In addition, the frequency of low expression of E-cadherin in pancreatic carcinomas with lymph node metastasis (68 %; 19/28) was significantly higher than in tumors without lymph node metastasis (44 %; 21/48). Correlation analysis demonstrated that the overexpression of AIB1 was inversely correlated with low expression of E-cadherin in pancreatic adenocarcinomas. Conclusion: Overexpression of AIB1 might promote invasion and metastasis of cancer cells and is associated with down-regulation of E-cadherin in pancreatic adenocarcinomas. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is an enteric pathogen of humans and animals, and pigs have been considered an important reservoir of this virus. Recent evidence has indicated the cross-species transmission of hepatitis E virus (HEV) from pigs to humans, causing zoonosis, mostly via consumption of uncooked or undercooked animal meat/viscera. In this study, we have developed a one-step RT-LAMP assay for rapid detection of swine HEV. Specific primer sets targeting the ORF3 gene were designed. The sensitivity of the RT-LAMP assay was 10 copies/μl of RNA template, which was tenfold higher than that of RT-nPCR. The specificity of this assay was demonstrated by the lack of amplification of DNA/RNA from other swine viruses. Furthermore, a total of 41 bile samples were subjected to RT-LAMP and RT-nPCR. Eighteen positive samples were detected by RT-nPCR, while 36 positive samples were detected by RT-LAMP, indicating that the sensitivity of the RT-LAMP assay was higher than that of the conventional RT-nPCR assay. The RT-LAMP assay reported here may be used for diagnosis of swine HEV, not only in laboratories but also under field conditions. [ABSTRACT FROM AUTHOR]

In this article, the traffic hydrodynamic model considering the driver’s reaction time was applied to the traffic analysis at the intersections on real roads. In the numerical simulation with the model, the pinch effect of the right-turning vehicles flow was found, which mainly leads to traffic jamming on the straight lane. All of the results in accordance with the empirical data confirm the applicability of this model. [ABSTRACT FROM AUTHOR]

In this paper, the properties of a reconfigurable device which realizes the omnidirectional band gaps (OBGs), nonreciprocity (NR) and polarization beam splitting (PBS) based on the one-dimensional (1-D) magnetized plasma photonic crystals (MPPCs) nested with quasi-periodic Pell and Thue–Morse sequences are theoretically investigated by the transfer matrix method (TMM). The obtained results show that the OBGs, the NR region, and the scope of PBS can be notably manipulated by the plasma frequency, plasma cyclotron frequency, incident angle, and the plasma collision frequency. More specifically, the higher plasma frequency is needed for accomplishing the property of OBGs while the better performance of NR can be achieved with a larger incident angle and a higher plasma cyclotron frequency. Also, the lower plasma frequency and higher plasma cyclotron frequency are suitable for the splendid performance of PBS. The augment of the plasma collision frequency is adverse to the properties as mentioned above. Due to the Voigt magneto-optical effect generating from the magnetized plasma layers, the time-reversal symmetry is destroyed which is beneficial for obtaining the properties of NR and PBS. Besides, owing to the nested technology which breaks the spatial symmetry of the structure further, compared with the conventional 1-D single quasi-periodic structures, the proposed nested MPPCs have a preeminent strength in achieving the three functions through modulating the corresponding physical parameters. These findings provide theoretical guidance for the design and application of the multifunctional devices. [ABSTRACT FROM AUTHOR]

Kinesin-3 and kinesin-1 molecular motors are two families of the kinesin superfamily. It has been experimentally revealed that in monomeric state kinesin-3 is inactive in motility and cargo-mediated dimerization results in superprocessive motion, with an average run length being more than 10-fold longer than that of kinesin-1. In contrast to kinesin-1 showing normally single-exponential distribution of run lengths, dimerized kinesin-3 shows puzzlingly Gaussian distribution of run lengths. Here, based on our proposed model, we studied computationally the dynamics of kinesin-3 and compared with that of kinesin-1, explaining quantitatively the available experimental data and revealing the origin of superprocessivity and Gaussian run length distribution of kinesin-3. Moreover, predicted results are provided on ATP-concentration dependence of run length distribution and force dependence of mean run length and dissociation rate of kinesin-3. [ABSTRACT FROM AUTHOR]

Intracellular transport is performed often by multiple motor proteins bound to the same cargo. Here, we study theoretically collective transport of the cargo by two kinesin motors. We propose that the motor has only the elastic interaction with the cargo via the linker connecting them and has no interaction with another motor. With parameters values for single motors from the available single-molecule data, we show that at linker's elastic strength K ≈ 0. 25 pN/nm the theoretical data of both velocity and run length of the two-motor assembly under no load are identical to the available experimental data. The run length distribution is single exponential. The single-motor-bound state of the assembly dominates the transport. Both the force dependence of the velocity of the cargo driven by single load-bearing motor and that by two load-bearing motors in the assembly are consistent with the experimental data. The stall force of the assembly is larger than the sum of stall forces of two uncoupled motors. Moreover, we predict that the stall force increases with the increase of K and becomes saturated at large K, with the saturated value being 1.5-fold larger than the sum of stall forces of the two uncoupled motors. [ABSTRACT FROM AUTHOR]

An oracle that correctly predicts the outcome of every particle physics experiment, the products of every possible chemical reaction or the function of every protein would revolutionize science and technology. However, scientists would not be entirely satisfied because they would want to comprehend how the oracle made these predictions. This is scientific understanding, one of the main aims of science. With the increase in the available computational power and advances in artificial intelligence, a natural question arises: how can advanced computational systems, and specifically artificial intelligence, contribute to new scientific understanding or gain it autonomously? Trying to answer this question, we adopted a definition of 'scientific understanding' from the philosophy of science that enabled us to overview the scattered literature on the topic and, combined with dozens of anecdotes from scientists, map out three dimensions of computer-assisted scientific understanding. For each dimension, we review the existing state of the art and discuss future developments. We hope that this Perspective will inspire and focus research directions in this multidisciplinary emerging field., Competing Interests: Competing interestsThe authors declare no competing interests., (© Springer Nature Limited 2022, Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)