Dual Chains Research Articles

DBPBFT: A hierarchical PBFT consensus algorithm with dual blockchain for IoT

The Internet of Things (IoT) is composed of smart devices connected to a network that can send and receive large amounts of data with other devices, generating a lot of data for processing and analysis. Due to the fact that every transaction in blockchain is recorded, placed in a data block, and added to an immutable and secure data chain, blockchain is becoming one of the most promising solutions for enhancing IoT security issues. As more devices become intelligent, the scale of IoT systems, including residential IoT and industrial IoT, is on the rise. Consequently, the issue of resource consumption, stemming from the escalating system communication overhead, is becoming more pronounced. In order to improve the efficiency of the consensus process for residential IoT and reduce the overhead caused by the consensus process, this paper proposes a hierarchical PBFT consensus algorithm With Dual Blockchain for IoT (DBPBFT). Compared to industrial IoT, DBPBFT is more suitable for residential IoT with small scope and clear data classification. DBPBFT separates the responsibilities of dual chains, improving system scalability while also enhancing blockchain security. A chain is divided into several small groups, each responsible for a type of data, reducing system overhead and communication overhead. To avoid unnecessary view-change as much as possible, before consensus begins, each group will select the current view primary node based on reputation values. The simulation results show that the DBPBFT algorithm is superior to traditional algorithms. In terms of reducing communication overhead, compared with EPBFT and DPNPBFT, DBPBFT has increased by 73.8% and 53.1%, respectively. In terms of consensus efficiency, DBPBFT has improved by 34% compared to DPNPBFT.

From global to national: The role of urban agglomerations in China's new development paradigm.

Urban agglomerations (UAs), which serve as pivotal hubs for economic and innovative convergence, play a crucial role in enhancing internal circulation and strengthening external linkages. This study utilizes the China city-level multi-regional input-output tables, incorporating the Dagum Gini coefficient and kernel density estimation methods, to perform a thorough quantitative analysis. Disparities within the national and global value chains ("dual value chains") of Chinese UAs from 2012 to 2017 were assessed. Additionally, the logarithmic mean Divisia index (LMDI) method was applied to disaggregate the drivers of both national and global intermediate inputs (NII and GII). The study's key findings include the following: (1) The national value chain (NVC) within UAs exhibits robust growth, contrasting with the decline in the global value chain (GVC). (2) The inter-UA disparity contribution rate significantly surpasses the combined rates of intra-UA contribution and super-variation density. (3) Distinct evolutionary peak trends are discerned among various UAs within the "dual value chains", highlighting diverse spatial polarization characteristics and expansiveness. (4) The growth of the NVC has transitioned from a negative to a positive impact on NII, while the decline in GVC has substantially counteracted GII growth. Economic and demographic factors notably drive positive improvements in both NII and GII, whereas the efficiency of outflows presents a negative driving effect. Based on these findings, this study offers strategic recommendations to facilitate the effective integration of UAs into the new development paradigm, thereby providing a scientific basis for related decision-making processes.

Enhanced Performance and Stability of Poly(carbazole)-Based Anion Exchange Membranes via Synergistic Dual Side Chains for Fuel Cell Applications

Enhanced Performance and Stability of Poly(carbazole)-Based Anion Exchange Membranes via Synergistic Dual Side Chains for Fuel Cell Applications

Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains

Building well-developed ion-conductive highways is highly desirable for anion exchange membranes (AEMs). Grafting side chain is a highly effective approach for constructing a well-defined phase-separated morphological structure and forming unblocked ion pathways in AEMs for fast ion transport. Fluorination of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine groups. However, their electronic effect on the alkaline stability of side chains and membranes is rarely reported. Here, fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane properties. The poly(binaphthyl-co-p-terphenyl piperidinium) AEM (QBNpTP) has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho- and meta-terphenyl based AEMs. Importantly, by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone, the prepared AEM (QBNpTP-QFC) presents an enhanced conductivity (150.6 mS cm−1) and a constrained swelling at 80 °C. The electronic effect of fluorinated side chains is contemplated by experiments and simulations. The results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms, increasing OH− attack on the C atom and improving the stability of piperidinium cations. Hence QBNpTP-QFC possesses a robust alkaline stability at 80 °C (95.3% conductivity retention after testing in 2 M NaOH for 2160 h). An excellent peak power density of 1.44 W cm−2 and a remarkable durability at 80 °C (4.5% voltage loss after 100 h) can be observed.

Synthesis and applications of a Y‐inimer with two orthogonal controlled free radical polymerization initiators

AbstractWe report the synthesis of a Y‐shaped inimer that contains two orthogonal initiators for ATRP and NMP. The inimer is synthesized through a one‐pot multi‐component reaction that vastly simplifies the typically cumbersome synthesis of similar compounds. The Y‐inimer has the versatility to be homopolymerized into a backbone for A/B Janus bottlebrush synthesis or copolymerized with glycidyl methacrylate (GMA) and cross‐linked into an ultra‐thin coating for mixed A/B brush growth from planar surfaces. Importantly, the Y‐shaped nature of the inimer ensures growth of A and B brushes are consistently in a 1:1 ratio. We demonstrate the application of the Y‐inimer in the synthesis of a PMMA/PS Janus bottlebrush as well as two different mixed A/B polymer brushes, one with the ability to microphase separate, and a second mixed polyelectrolyte brush with opposite charges. The inimer is compatible with various A/B monomer systems and offers a universal approach to the “grafting‐from” polymerization of dual vinyl polymer side chains. This study provides a unique way of utilizing multi‐component reactions in polymer chemistry to access complex functional architectures.

Ammoniated Zinc Oxide Nanoparticles for Preparing High-Melt-Performance Poly(lactic acid) Bearing Dual Hybrid Long-Branched Chains by Degrading and Restructuring Chains

Ammoniated Zinc Oxide Nanoparticles for Preparing High-Melt-Performance Poly(lactic acid) Bearing Dual Hybrid Long-Branched Chains by Degrading and Restructuring Chains

Optimal and heuristic policies for production and inventory controls in dual supply chains with fluctuating demands

AbstractIn the context of fast‐fashion business, we study the joint control of production, inventory, and unilateral transshipment in dual supply chains in which one supply chain is a responsive supply chain for fashion products and the other is an efficient supply chain for basic products in a fluctuating demand environment (FDE). Our research focuses on: (1) formulating an appropriate model for this complex problem; (2) characterizing the structured optimal policy, which can be used to develop effective heuristic policies; and (3) generalizing our studies for more applications. To address these issues, we formulate a discrete‐time finite‐horizon stochastic dynamic program model in which FDE is represented by a world state evolving in accordance with the discrete‐time Markov chain. The supply chain for the fashion product is modeled by a two‐stage tandem production system with a make‐to‐stock (MTS) stage for the fabric and a subsequent MTS stage for finished fashions. In parallel, the supply chain for the basic products is also modeled by a two‐stage tandem production system with a MTS stage for the fabric and a subsequent make‐to‐order (MTO) stage for finished basics. Further, the two supply chains are coupled via the unilateral transshipment of fabric with random transshipment time. By value iteration, we characterize the optimal policy for the single‐product problem with a set of monotone switching surfaces. The results are extended to the multi‐product multi‐supplier case. Further, based on the structure of the optimal policy, we develop a heuristic policy for the multi‐dimensional dynamic program model. From a practice perspective, we demonstrate the value of transshipment and controlled transshipment, analytically and numerically, and therefore justify the establishment of two separate local manufacturing bases in dual supply chains. Additionally, to achieve both quick response and efficiency, we show that the total cost can be reduced significantly if sufficient fabric is prepared just in time (JIT) for in‐season production at the beginning of a season.

Design, synthesis, and biological evaluation of a potential long-acting glucagon-like peptide-1 (GLP-1) analog

By binding to its receptor, glucagon-like peptide-1 (GLP-1) plays various physiological roles, including activating glucose-dependent insulin secretion, inhibiting gastric emptying, and reducing appetite. This suite of activities makes GLP-1 and its analogs an attractive choice for treating type 2 diabetes mellitus in the context of overweight or obesity. This study used different types and lengths of fatty acids to design dual fatty acid side chains for GLP-1 receptor agonists including decanoic, dodecanoic, tetradecanoic, hexadecanoic, dodecanedioic, tetradecanedioic, hexadecanedioic, and octadecanedioic acids. Sixteen GLP-1 receptor agonists (conjugates 13–28) with dual fatty acid side chains were obtained by liquid-phase synthesis. After structural confirmation using high-resolution mass spectrometry, peptide mapping, and circular dichroism, the biological activities of the conjugates were screened. First, the conjugates were screened for albumin binding and activity in GLP-1R-CRE-bla CHO-K1 cells. Albumin binding results suggested a synergistic effect between the two fatty acids in the conjugates. Next, conjugates 18, 19, and 21 selected after primary screening were assessed for receptor affinity, activity in INS-1 cells, plasma stability across different species, and efficacy and pharmacokinetics in normal and db/db mice. One candidate (conjugate 19) was found to have albumin binding of >99 %, good receptor affinity, activities of INS-1 cells, and plasma stability. We found that cellular activities in GLP-1R-CRE-bla CHO-K1 cells and pharmacodynamics and pharmacokinetics in normal and db/db mice for conjugate 19 were superior to those of semaglutide.

Tracing the regional dual value chains: Measurement on the production position and evidence from China

When there is insufficient internal and external impetus for developing countries’ economy, building a domestic and international dual circulation is conducive to promoting the regional industrial growth. On the basis of regional embedded international input-output tables, this paper extends the measurement framework of production position and proposes the concept of the dual value chain, which measure production position that unifies the national and global value chains from forward and backward industrial linkages. We decompose the national and global value chains into three categories and investigate the production position characteristics of China with a multi-dimensional perspective. Consistent evidence shows that a feasible path of technological progress in optimizing the production in value chains in which technological progress plays a crucial role on the pure national value chain across the high-tech manufacturing sector, the eastern and central regions. Their posterior probabilities are 0.96, 0.21and 0.86, respectively. Moreover, the impact on the dual production is nonnegligible that the posterior probability of technological progress on the eastern and central regions is 0.40 and 0.92. In addition, the impact of the Chinese economic stimulus program and technological progress on the economic crisis has a certain moderating effect. Our proposed evaluation framework sheds new light that national value chain production can boost economic growth，and further promote the coordinated of regional industries for developing countries.

Integrating space syntax with spatial interaction

In this paper, we attempt to compare space syntax with spatial interaction. At one level, these two approaches to urban spatial structure are non-comparable. Space syntax is largely a descriptive technique for visualising spatial relations at the level of connections between places while spatial interaction is a predictive model that forecasts how much travel there will be between places. Space syntax articulates the system in terms of whether or not a physical link, usually at the level of the street, exists while spatial interaction predicts movements between all origins and destinations which are places often anchored in terms of the street network, but which at the level of prediction, assume connections between all places. Space syntax is grounded at a fine spatial scale while spatial interaction defines places as aggregates of activity in larger zones than the scale of the street system. The main output of space syntax is a connectivity matrix of step lengths between streets whereas in spatial interaction, such networks are predetermined, measurable in terms of Euclidean distance or generalised cost of travel, and the output is the volume of travel prior to this being assigned usually to a street network.There is however a fundamental way of relating the implicit network graph of spatial interaction to the explicit planar graph of the street network. We begin by assuming the planar graph of the network is conceived of as a primal problem of spatial interaction while the dual graph linking streets in the planar graph is the graph which is used in space syntax. We exploit this duality and show how we can move easily between spatial interaction as the primal and space syntax as the dual. This is rooted in a more fundamental graph – the bipartite graph which is a list of streets/arcs and their intersections/nodes from which the primal and dual emerge naturally. We explore various accessibility measures and show how they relate and correlate. We then go one step further and consider how various processes of random walking take place in these networks examining the steady states of the primal and dual problems in terms of the likelihood of a random walker visiting any node or street. We thus define primal and dual Markov chains that enable us to generate these probabilities. This provides a basic framework for comparing primal and dual in comparing spatial interaction with space syntax. We illustrate these measures on simple and easy to articulate graphs, extending this to a synthetic network of nearest neighbour links in Greater London based on 699 nodes and 1972 symmetric ‘streets’ between zones. This is a preliminary attack on the problem of linking these two approaches although many challenges remain.

Integrated Development of the Yangtze River Delta Region: Status, Problems and Optimization

The Yangtze River Delta region is a region with one of the highest degrees of regional integrations in China, and the prosperous growth of this area has a significant bearing on China’s economic progress. In recent years, China’s development has faced drastic changes in the global development environment in the general environment of reverse globalization and post-epidemic era, in this regard, China has put forward the development strategy of internal and external double circulation based on the domestic grand circulation, which further requires the rapid development of regional integration to reduce the barriers to factor flow within the existing domestic administrative regions and promote the formation of a large market; promote the contraction and restructuring of industrial chains and supply chains to enhance their security and adaptability in the face of environmental changes. This paper concludes the development and current problems of regional integration in the Yangtze River Delta, including the inadequate oversight and appraisal mechanisms and guarantees mechanisms for interregional cooperation, the lack of integration of dual chains, the urgent need to enhance the construction of ecofriendly ecological sustainability, and a proposal.

Cross-Linking Network of Soft–Rigid Dual Chains to Effectively Suppress Volume Change of Silicon Anode

Polyacrylic acid (PAA) is a promising binder for the high-capacity Si anode. However, the one-dimensional structure of PAA could cause the linear molecular chains to slide from the Si surface during the charge-discharge processes, leading to insufficient suppression of the massive volume expansion of the Si anode. Herein, a soft-rigid dual chains' network of PAA-sodium silicate (PAA-SS) was successfully constructed by cross-linking PAA and SS in situ at room temperature. The soft chains of PAA and the rigid chains of polysilicic acid synergistically ensure the enhanced adhesion property and mechanical strength. Therefore, the Si electrode with PAA-SS binder delivers a discharge capacity of 1559 mAh/g after 150 cycles at 4.2 A/g (1C) with an initial Coulombic efficiency of 93.2%. Moreover, the PAA-SS based SiC-500 electrode exhibits a discharge capacity of 441 mAh/g with the capacity retention of 88.2% after 500 cycles at 0.5 A/g, implying the PAA-SS binder's great industrial prospect in Si based electrodes.

Photoactivatable Materials for Versatile Single-Cell Patterning Based on the Photocaging of Cell-Anchoring Moieties through Lipid Self-Assembly.

Versatile methods for patterning multiple types of cells with single-cell resolution have become an increasingly important technology for cell analysis, cell-based device construction, and tissue engineering. Here, we present a photoactivatable material based on poly(ethylene glycol) (PEG)-lipids for patterning a variety of cells, regardless of their adhesion abilities. In this study, PEG-lipids bearing dual fatty acid chains were first shown to perfectly suppress cell anchoring on their coated substrate surfaces whereas those with single-chain lipids stably anchored cells through lipid-cell membrane interactions. From this finding, a PEG-lipid with one each of both normal and photocleavable fatty acid chains was synthesized as a material that could convert the chain number from two to one by exposure to light. On the photoconvertible PEG-lipid surface, cell anchoring was activated by light exposure. High-speed atomic force microscopy measurements revealed that this photocaging of the lipid-cell membrane interaction occurs because the hydrophobic dual chains self-assemble into nanoscale structures and cooperatively inhibit the anchoring. Light-induced dissociation of the lipid assembly achieved the light-guided fine patterning of multiple cells through local photoactivation of the anchoring interactions. Using this surface, human natural killer cells and leukemia cells could be positioned to interact one-by-one. The cytotoxic capacity of single immune cells was then monitored via microscopy, showing the proof-of-principle for applications in the high-throughput analysis of the heterogeneity in individual cell-cell communications. Thus, the substrate coated with our photoactivatable material can serve as a versatile platform for the accurate and rapid patterning of multiple-element cells for intercellular communication-based diagnostics.

Dual and Multi-channel closed-loop supply chains: A state of the art review

Dual and Multi-channel closed-loop supply chains: A state of the art review

Research on Pricing and Service Level Strategies of Dual Channel Reverse Supply Chain Considering Consumer Preference in Multi-Regional Situations.

Facing the increasingly serious waste electrical and electronic equipment (WEEE) recycling problem, recycling enterprises actively introduce online recycling channels, build dual channel reverse supply chains (DRSC), and use high-level recycling price and service levels to enhance consumers’ recycling enthusiasm and recycling amount. Nevertheless, in China, where the imbalance of regional development is widespread, the recycling center, third-party recycler (TPR), and third-party platform (TPP) are faced with the choices of pricing and service level when facing multi-regional consumers. This paper mainly answers the following questions: (1) When the recycling center and TPP introduce online recycling channels in multi-regional situations, how should they set online recycling price, transfer price, and service level? (2) When consumer preference for online channels changes in a certain region, how should recycling enterprises adjust their optimal pricing and service level decisions for different regions to maximize their own profits? How do the profits of recycling enterprises change? In order to solve the above problems, in this paper, we propose three pricing and service level decision models for the recycling center with online channels, namely, keeping prices unchanged, unifying all prices, and maximizing its own profits. By using the Stackelberg game to solve the model, we get the optimal pricing, service level decisions, as well as the maximum profits of the recycling center, TPP, and TPR when consumer preference changes. By analyzing the results of the model, we find that the change of consumer preference for online channels in a certain region will affect the decision and profits of multi-regional recycling enterprises. Specifically, consumer preference for online channels in a certain region will not only lead to an increase in the profits of the recycling center and TPP and a decrease in the profit of local TPRs, but also an increase in the profit of TPRs in other regions. In addition, at the beginning of introducing online channels, the recycling center can adopt two strategies to avoid conflicts among channels: keeping offline transfer prices unchanged and unifying all transfer prices, but the former promotes its economic profits more significantly.

Rapid transport of germ-mimetic nanoparticles with dual conformational polyethylene glycol chains in biological tissues.

Polyethylene glycols (PEGs) can improve the diffusivity of nanoparticles (NPs) in biological hydrogels, while extended PEG chains severely impede cellular uptake of NPs. Inspired by invasive germs with flagellum-driven mucus-penetrating and fimbriae-mediated epithelium-adhering abilities, we developed germ-mimetic NPs (GMNPs) to overcome multiple barriers in mucosal and tumor tissues. In vitro studies and computational simulations revealed that the tip-specific extended PEG chains on GMNP functioned similarly to flagella, facilitating GMNP diffusion (up to 83.0-fold faster than their counterparts). Meanwhile, the packed PEG chains on the bodies of GMNP mediated strong adhesive interactions with cells similarly to the fimbriae, preserving cellular uptake efficiency. The in vivo results proved the superior tumor permeability and improved oral bioavailability provided by the GMNP (21.9-fold over administration of crystalline drugs). These findings offer useful guidelines for the rational design of NPs by manipulating surface polymer conformation to realize multiple functions and to enhance delivery efficacy.

Arenicolins: C-Glycosylated Depsides from Penicillium arenicola.

During investigation of the secondary metabolism of four strains of Penicillium arenicola, two new depsides, arenicolins A (1) and B (2), were isolated and characterized. Their structures were established mainly by analysis of NMR and HRMS data and by comparison with known compounds. These depsides incorporate intriguing structural features, including dual alkyl side chains and a C-glycosyl unit, with 1 also containing an acylated 2-hydroxymethyl-4,5,6-trihydroxycyclohexenone moiety. Although the arenicolins were produced by all strains tested, arenicolin A (1) was obtained using only one of five medium compositions employed, while arenicolin B (2) was produced in all media tested. Neither compound showed antibacterial or antifungal activity, but 1 exhibited cytotoxicity toward mammalian cell lines, including colorectal carcinoma (HCT-116), neuroblastoma (IMR-32), and ductal carcinoma (BT-474), with IC50 values of 7.3, 6.0, and 9.7 μM, respectively.

Competition strategy and governance policy for the dual international supply chains under trade war

ABSTRACT Against the backdrop of the full-blown trade war, this study investigates the price discrimination strategies and tariff policies for the dual international supply chains in trade war via game-theoretical modeling and numerical and sensitivity analyses approaches. Three key findings from the study are: (1) both the free trade and trade war scenarios are bilateral and stable, and the free trade scenario is preferable to the trade war scenario. (2) in free trade scenario, the combination of free competition strategy and ‘actionless governance’ policy forms a ‘win-win’ state, which is the best choice for all trade stakeholders from the perspective of long-term sustainable development. (3) in trade war scenario, the combination of aggressive price discrimination strategy and tit-for-tat tariff counterattack policy forms a ‘prisoner’s dilemma’ state.

Cluster Self-Organization of Intermetallic Systems: 124-Atom Cluster 0@12@32@80 and 44-Atom Cluster 0@12@32 for the Self-Assembly of Li48Na80Ga332-oF920 Crystal Structure

A combinatorial and topological analysis has been performed and self-assembly of the Li48Na80Ga332-oF920 crystal structure has been simulated (sp. gr. Fmmm, a = 24.666 A, b = 15.974 A, c = 45.271 A, V = 17 837 A3) using computer methods (the TOPOS program package). It is found that there are 11 827 versions of cluster representation of an atomic 3D net with the number of structural units from 4 to 14. Two framework-forming icosahedral clusters ico-K124 and ico-K44 are determined. The chemical composition of the shells of the three-layer 124-atom nanocluster ico-K124 is 0@12(Ga12)@32(Li20Ga12)@80(Li4Na16Ga60), its diameter is 17 A, and the symmetry is mmm. The chemical composition of the shells of the two-layer 44-atom nanocluster ico-K44 is 0@12(Ga12)@32(Li20Ga12), its diameter is 11 A, and the symmetry is 2/m. The symmetry and topology code of self-assembly of the crystal structure has been reconstructed from iсо-K124 and ico-K44 nanocluster precursors in the following form: primary chain → layer → framework. Ga7 clusters and dual chains of Ga atoms occupy 3D-framework voids.

Asymptotic Correlations in Gapped and Critical Topological Phases of 1D Quantum Systems

Topological phases protected by symmetry can occur in gapped and—surprisingly—in critical systems. We consider non-interacting fermions in one dimension with spinless time-reversal symmetry. It is known that the phases are classified by a topological invariant omega and a central charge c. We investigate the correlations of string operators, giving insight into the interplay between topology and criticality. In the gapped phases, these non-local string order parameters allow us to extract omega . Remarkably, ratios of correlation lengths are universal. In the critical phases, the scaling dimensions of these operators serve as an order parameter, encoding omega and c. We derive exact asymptotics of these correlation functions using Toeplitz determinant theory. We include physical discussion, e.g., relating lattice operators to the conformal field theory. Moreover, we discuss the dual spin chains. Using the aforementioned universality, the topological invariant of the spin chain can be obtained from correlations of local observables.