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In today's fast-paced and ever-changing environment, the need for algorithms with enhanced global optimization capability has become increasingly crucial due to the emergence of a wide range of optimization problems. To tackle this issue, we present a new algorithm called Random Particle Swarm Optimization (RPSO) based on cosine similarity. RPSO is evaluated using both the IEEE Congress on Evolutionary Computation (CEC) 2022 test dataset and Convolutional Neural Network (CNN) classification experiments. The RPSO algorithm builds upon the traditional PSO algorithm by incorporating several key enhancements. Firstly, the parameter selection is adapted and a mechanism called Random Contrastive Interaction (RCI) is introduced. This mechanism fosters information exchange among particles, thereby improving the ability of the algorithm to explore the search space more effectively. Secondly, quadratic interpolation (QI) is incorporated to boost the local search efficiency of the algorithm. RPSO utilizes cosine similarity for the selection of both QI and RCI, dynamically updating population information to steer the algorithm towards optimal solutions. In the evaluation using the CEC 2022 test dataset, RPSO is compared with recent variations of Particle Swarm Optimization (PSO) and top algorithms in the CEC community. The results highlight the strong competitiveness and advantages of RPSO, validating its effectiveness in tackling global optimization tasks. Additionally, in the classification experiments with optimizing CNNs for medical images, RPSO demonstrated stability and accuracy comparable to other algorithms and variants. This further confirms the value and utility of RPSO in improving the performance of CNN classification tasks. [ABSTRACT FROM AUTHOR]

The Kelvin relation, relating the Seebeck coefficient and the Peltier coefficient, is a theoretical basis of thermoelectricity. It was first derived by Kelvin using a quasi-thermodynamic approach. However, Kelvin's approach was subjected to much criticism due to the rude neglect of irreversible factors. It was only later that a seemingly plausible proof of the Kelvin relation was given using the Onsager reciprocal relation with full consideration of irreversibility. Despite this, a critical issue remains. It is believed that the Seebeck and Peltier effects are thermodynamically reversible, and therefore, the Kelvin relation should also be independent of irreversibility. Kelvin's quasi-thermodynamic approach, although seemingly irrational, may well have touched on the essence of thermoelectricity. To avoid Kelvin's dilemma, this study conceives the physical scenarios of equilibrium thermodynamics to explore thermoelectricity. Unlike Kelvin's quasi-thermodynamic approach, here, a completely reversible thermodynamic approach is used to establish the reciprocal relations of thermoelectricity, on the basis of which the Kelvin relation is once again derived. Moreover, a direct thermodynamic derivation of the Onsager reciprocal relations for fluxes defined as the time derivative of an extensive state variable is given using the method of equilibrium thermodynamics. The present theory can be extended to other coupled phenomena. [ABSTRACT FROM AUTHOR]

As the basic unit and micro-site of grassroots governance, rural communities are facing many cultural obstacles that restrict rural modernization. Focused on rural communities, this study sorts out the requirements of Chinese-style modernization on rural communities and the actual performance of coping with the cultural obstacles of Chinese-style modernization. It finds that the causes of these cultural dilemmas are mainly due to the disconnection of the system in the process of modernization, the deviation between concept penetration and the actual situation. On this basis, this paper proposes the corresponding cultural solution strategies. These strategies start from the top-level design of the national system, cultivate the concept of modern cultural inheritance, construct a modern cultural development system, shape a modern cultural integration mechanism, and improve modern cultural governance and service models. They are of great significance to continuously cultivating the rural cultural self-confidence of the peasant masses, meeting the spiritual needs of the peasant masses, realizing the value goals of the peasant masses, and promoting the realization of Chinese-style modernization. [ABSTRACT FROM AUTHOR]

Hybrid energy harvesting systems are broadly applied in various fields due to the advantage of improving energy harvesting efficiency. In actual environment, there are many complex phenomena exhibiting jump, flights, rare transition features, and intermittent features, which can be described by systems subjected to non-Gaussian Lévy process. Sometimes, it is difficult to build mathematical models of complex hybrid energy harvesting systems precisely, especially for those driven by non-Gaussian Lévy noise. With the development of simulation capabilities and observing techniques recently, massive noise measurement data or simulating data can be feasibly obtained and there are many existing techniques devoted to discovering governing laws from abundant data. In this paper, we aim to extract the system equations from observed data influenced by non-Gaussian Lévy noise via using a data-driven method. The expressions of drift term, diffusion term and Lévy term can be approximated with the help of Fokker-Planck equation and non-local Kramers-Moyal formulae, and the coefficients of the expressions are learned by utilizing a sparse regression approach in the least square sense. Three examples are given to demonstrate the effectiveness of the method. Results show that the approach can well be applied to not only hybrid energy harvesting systems under Gaussian Brownian process but also the systems subjected to non-Gaussian Lévy process. Additionally, the relations between the demarcation parameter and an indicator denoted as Ratio for different time steps are analyzed, and results demonstrate that the indicator can be regarded as the criterion of selecting the appropriate demarcation parameter. [ABSTRACT FROM AUTHOR]

At present, the traditional scheduling mode of power grids generally dispatches according to the power generation cost within the safe range. Transmission costs are evenly distributed to customers according to their load ratios. There are no methods for the rational distribution of transmission costs according to the utilization degree of generation and load to transmission network resources. This traditional scheduling mode will render transmission cost distribution unfair, and it is difficult to guide reasonable load distribution in time and space. Therefore, an optimal economic scheduling method for power systems based on the whole-system-cost electricity price is proposed in this paper. For the power generation and the transmission sides, the whole-system-cost electricity price model was constructed according to the power flow tracking method. For the load side, a demand-side response model of users' responses to electricity price changes was established. Finally, the IEEE 57 node standard model was used to simulate optimal economic scheduling. The results show that the proposed method can guide the rational distribution of power flow. The power flow is shifted moderately from far away to near the power generation center, allowing for the load demand to be guided to meet nearby customers' demands and preventing the line from blocking, the latter of which is conducive to ensuring the safety of the power grid. [ABSTRACT FROM AUTHOR]

In order to solve the problem of randomness and volatility caused by the rapid growth of renewable energy (RE), energy storage systems (ESSs)—as an important means of regulation—can effectively improve the flexible regulation capacity of power systems utilizing a high proportion of RE. Most of the current ESS capacity configuration procedures are carried out based on the typical scenario method or time series production simulation. This method tends to determine the size of the ESS configuration through multiple trial simulations. Uncertainty of simulation prediction data can result in the existence of an excess capacity or lack of configured capacity. In addition, this method reflects the ESS demand under specific targets, but it fails to fully utilize RE generation characteristics. The configuration process lacks the mathematical mechanism of RE consumption, and the calculation process is too complicated. In view of the shortcomings of traditional ESS optimal configuration methods, this paper examines the mathematical mechanism of RE consumption and proposes the ESS optimal configuration analysis method based on "equal area criterion". First, the principle of RE consumption is analyzed and the "RE consumption characteristic curve" is proposed according to RE characteristics. In addition, a working principle diagram of RE consumption, including ESS, is constructed to visually show the consumption capacity of RE and the working position of ESS. Then, the ESS optimal configuration process, based on the "equal area criterion", is proposed to achieve an accurate match between ESS capacity demand and RE consumption targets. Finally, the power grid of a region in China is taken as an example. We prove that the proposed method can save 1.41 × 103 MWh of ESS capacity and provide a more "mathematical" and "convenient" systematic solution for RE consumption and ESS optimization compared to the production simulation method. [ABSTRACT FROM AUTHOR]

Transnational political communication today is being reconfigured by digital technologies and global power transition. Authoritarian state actors such as China are increasingly active on global social media platforms such as Twitter to directly advance their preferred frames with foreign publics in Western democracies, most notably in what could be called Chinese Twiplomacy contesting narrative globally over contentious issues. This paper problematises such Twiplomacy from authoritarians to Western democracies as 'networked transnational frame contestation', arguing that the political and cultural distance between the sending and target countries, the networked affordance of social media, and the national prism of the target countries, all contribute importantly to the complexity of such frame contestation. Through a case study on China's Twiplomacy in contesting coronavirus narrative in the UK, this paper further provides empirical evidence on how 'networked transnational frame contestation' works between politically and culturally distant countries. Using a mixed-method approach combining social network analysis and discourse analysis, this study finds that China's emotion-evoking discursive strategy draws traction but the authoritarian nature of the highly centralised networkedness and that of its discursive strategy, together with the strong cultural discordance with British publics, lead to networked recontextualisation of its intended frames in Britain. British publics, heavily relying on British political elites and press for foreign affairs, invoke shared cultural reference to recontextualise Chinese frames into culturally resonant counterframes. This study proposes a paradigm of 'networkedness within cascades' to understand frame contestation between politically and culturally distant countries. [ABSTRACT FROM AUTHOR]

The randomness of the power supply side and the load side of comprehensive energy systems is increasingly prominent. It is very difficult to meet demand through traditional planning methods. To solve this problem, this paper explores the coordinated planning of a power system under uncertain characteristics using the multilinear Monte Carlo method. The uncertain characteristic model and probability density function of the system's power supply side and load side are established. Taking the optimal operating cost and the maximum wind power consumption as the system planning objectives, a system coordination planning scheme is established, and it is solved by multilinear Monte Carlo simulation. The superiority of this method is verified by taking the modified IEEE 39-bus test system as an example. This method can provide a reference for system planning. [ABSTRACT FROM AUTHOR]

Cisplatin (CPT) is one of the standard treatments for hepatocellular carcinoma (HCC). However, its use is limits as a monotherapy due to drug resistance, and the underlying mechanism remains unclear. To solve this problem, we tried using canagliflozin (CANA), a clinical drug for diabetes, to reduce chemoresistance to CPT, and the result showed that CANA could vigorously inhibit cell proliferation and migration independent of the original target SGLT2. Mechanistically, CANA reduced aerobic glycolysis in HCC by targeting PKM2. The downregulated PKM2 directly bound to the transcription factor c-Myc in the cytoplasm to form a complex, which upregulated the level of phosphorylated c-Myc Thr58 and promoted the ubiquitination and degradation of c-Myc. Decreased c-Myc reduced the expression of GLS1, a key enzyme in glutamine metabolism, leading to impaired glutamine utilization. Finally, intracellular glutamine starvation induced ferroptosis and sensitized HCC to CPT. In conclusion, our study showed that CANA re-sensitized HCC to CPT by inducing ferroptosis through dual effects on glycolysis and glutamine metabolism. This is a novel mechanism to increase chemosensitivity, which may provide compatible chemotherapy drugs for HCC. [Display omitted] • Canagliflozin suppresses hepatocellular carcinoma via PKM2 but not SGLT2. • Canagliflozin-triggered inhibition of aerobic glycolysis induces impaired glutamine utilization in hepatocellular carcinoma. • PKM2 was confirmed to function as a PKM2-c-Myc complex on canagliflozin treatment. • Canagliflozin combined with cisplatin has a synergistic effect on hepatocellular carcinoma and overcome cisplatin resistance. [ABSTRACT FROM AUTHOR]

Thermodynamics contains rich symmetries. These symmetries are usually considered independent of the structure of matter or the thermodynamic state where matter is located and, thus, highly universal. As Callen stated, the connection between the symmetry of fundamental laws and the macroscopic properties of matter is not trivially evident. However, this view is now being challenged. Recently, with symmetry to the ideal gas equation of state (EOS), an ideal dense matter EOS has been proposed, which has been verified to be in good agreement with the thermodynamic properties of high-density substances. This indicates that there is a certain symmetry between the thermodynamic properties of substances in their high- and low-density limits. This paper focuses on the distinctive features and the significance of this symmetry. It is a new class of symmetry that is dependent on the thermodynamic state of matter and can be incorporated into the existing symmetrical theoretical system of thermodynamics. A potential path for developing the EOS theory arising from this symmetry is discussed. EOS at high densities could be developed by correcting or extrapolating the ideal dense matter EOS based on this symmetry, which might fundamentally solve the difficulty of constructing EOS at high densities. [ABSTRACT FROM AUTHOR]

A general and simple equation of state (EOS) is a rich source for research and discussion. Experience shows that high-density matter exhibits simple regularities and some "universal" EOSs have been established. Here, we present an ideal dense matter EOS that is symmetric to the ideal gas EOS by means of Oettingen's dual approach. The ideal dense matter EOS makes no assumptions about the structure of matter and is, therefore, general. Thermodynamic symmetry requires that the ideal dense matter EOS has better agreements with matter at higher densities, which is supported by some empirical equations and actual property data of various substances. Two derivative variables that have historically been overlooked, i.e., the specific work at constant entropy and the specific work at constant temperature, are rejuvenated in the ideal dense matter EOS. Additionally, we find another physical constant related to thermodynamic property of matter symmetric to the ideal gas constant and further give its estimated values for several common substances. Thermodynamic symmetry suggests that the ideal dense matter EOS has the same theoretical location as the ideal gas EOS. It is another basis for the EOS theory and enriches the dual framework of thermodynamics. [ABSTRACT FROM AUTHOR]

Urban agglomerations are regions where the economy and population are highly concentrated, which are also spatial units with more concentrated carbon emissions. A detailed decomposition of driving factors based on changes in carbon emissions of urban agglomerations can provide a reference for better carbon reduction policies. In this paper, we establish an evaluation framework of carbon emission drivers of urban agglomeration from the perspective of CO2 generation and removal using a system dynamics method. The key influencing factors and optimal emission reduction measures of carbon emissions in urban agglomerations are explored. The results are as follows: (1) The industrial structure is the key influencing factor of carbon emissions; (2) compared with no implementation of any policies, the total carbon emissions and carbon emission intensity of integrated policies all significantly decrease, with a decrease of 43.68% and 53.32%, respectively in 2035; (3) energy structure adjustment has a significant effect in reducing carbon emissions and carbon emission intensity; (4) the role of increasing investment in technological innovation in ensuring achievement of "carbon peak" should not be ignored. It is found that integrated policies often exhibit a better emission reduction effect, but this effect is not a simple summation of the effects of each single policy. [ABSTRACT FROM AUTHOR]

The integrated energy system is a complex energy system that involves multi-stakeholder and multi-energy coordinated operations. The key to improving its scale and sustainable development is to construct a better-integrated energy system dispatching method which is suitable for the power market. However, the randomness of the supply side and load side of the integrated energy system brings further challenges to system planning and scheduling. Therefore, the optimal scheduling method of an integrated energy system considering the uncertainty of supply and demand in the market environment is studied in this paper. Firstly, the uncertainty models of the supply side and load side of the integrated energy system are established. Then, the optimal scheduling model based on robust chance constraint is established. The reserve capacity constraint is set as a chance constraint with a certain confidence level to maximize the system profit in the power market. Finally, simulations show that the proposed method not only guarantees the robustness of the system but also improves the economy of the system. The method provides ideas for exploring the development mechanism and strategy of integrated energy systems in the electricity market environment. [ABSTRACT FROM AUTHOR]

Background: Streptococcus pneumoniae is a gram-positive opportunistic pathogen, and infection risks of S. pneumoniae can be profoundly augmented by its acquired multidrug-resistance (MDR). The rapid development of MDR in S. pneumoniae was attributed to the international dissemination of a small number of multidrug-resistant "clones." Clonal complex (CC) 271 is a prevalent MDR CC in the world and the most prevalent CC in China. However, the evolutionary trajectories of multidrug-resistant S. pneumoniae CC271 in China still are largely unknown. Methods: We investigated a collection of 1312 S. pneumoniae isolates collected from 28 tertiary hospitals in China from 2007 to 2020. Recombination prediction and recombination-masked phylogenetic analysis were combined to determine the population structure and mode of evolution of CC271. Data from the Global Pneumococcal Sequencing program (GPS) were combined to understand the global distribution of clones identified in this study. Bayesian analysis were recruited to analysis the evolutionary dynamics of dominant clones within CC271 in China. Results: The phylogenomic analysis resulted in the discovery of two globally distributed clones, ST271-A and ST271-B. ST271-A was a derivative of ST236 and an ancestor of ST271-B and ST320, refining the internal phylogenetic relationship of CC271. ST271-B was the most dominant clone in China, with higher β-lactam resistance especially for cephalosporins comparing to other MDR clones. Bayesian skyline plot showed a rapid expansion of 19F ST271-B from 1995 to 2000, which correlates with the widespread use of cephalosporins in the 1990s in China. 19A ST320, a vaccine-escape clone, is the second largest population in China. The Bayesian skyline plot showed that the 19A ST320 began to expand rapidly around 2001, which appeared to coincide with the prevalence of 19A after application of PCV7 in 2000 in the USA. We also observed frequent transmission of 19A ST320 between countries. It suggests that mass vaccination in some countries could affect the prevalence of clones in unvaccinated countries in the context of high-frequency international transmission. Conclusions: Our results refined the internal phylogenetic relationship of CC271, showing that the 19F ST271-B and 19A ST320 evolved independently from ST271-A, with different histories and driving forces for their evolution and dissemination in China. [ABSTRACT FROM AUTHOR]

Long-distance dispersal (LDD) beyond the range of a species is an important driver of ecological and evolutionary patterns, but insufficient attention has been given to postdispersal establishment. In this review, we summarize current knowledge of the post-LDD establishment phase in plant colonization, identify six key determinants of establishment success, develop a general quantitative framework for post-LDD establishment, and address the major challenges and opportunities in future research. These include improving detection and understanding of LDD using novel approaches, investigating mechanisms determining post-LDD establishment success using mechanistic modeling and inference, and comparison of establishment between past and present. By addressing current knowledge gaps, we aim to further our understanding of how LDD affects plant distributions, and the long-term consequences of LDD events. Dispersal is a central process in the ecology and evolution of living organisms, reducing inbreeding and competition, shaping local spatial dynamics, and allowing tracking of establishment opportunities in changing environments. Long-distance dispersal (LDD), beyond the range of a species, is rare and cannot be studied directly, but it is a central process in biogeography, contributing to both the assembly of natural biotas over millions of years and the spread of invasive species during the Anthropocene. Studies of plant LDD at biogeographical scales have focused on the initiation and transport stages but have paid little attention to the subsequent establishment stage, although establishment is necessary for LDD to impact biogeography. Establishment success is influenced by many factors, including propagule pressure, functional traits, extreme events and anthropogenic disturbances, interactions with predators, competitors and mutualists, niche flexibility, and Allee effects. We integrate quantitative LDD frameworks with phylogeographic tools to provide a general framework for estimating the probability of colonizing a new site. This integration between biogeography and movement ecology is expected to yield important new tools and insights into the interplay between ecology, evolution, and biogeography in shaping patterns of biodiversity. [ABSTRACT FROM AUTHOR]

Stomatal closure is regulated by plant hormones and some small molecules to reduce water loss under stress conditions. Both abscisic acid (ABA) and polyamines alone induce stomatal closure; however, whether the physiological functions of ABA and polyamines are synergistic or antagonistic with respect to inducing stomatal closure is still unknown. Here, stomatal movement in response to ABA and/or polyamines was tested in Vicia faba and Arabidopsis thaliana, and the change in the signaling components under stomatal closure was analyzed. We found that both polyamines and ABA could induce stomatal closure through similar signaling components, including the synthesis of hydrogen peroxide (H2O2) and nitric oxide (NO) and the accumulation of Ca2+. However, polyamines partially inhibited ABA‐induced stomatal closure both in epidermal peels and in planta by activating antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), to eliminate the ABA‐induced increase in H2O2. These results strongly indicate that polyamines inhibit abscisic acid‐induced stomatal closure, suggesting that polyamines could be used as potential plant growth regulators to increase photosynthesis under mild drought stress. [ABSTRACT FROM AUTHOR]

In 2019, Schilling et al. claimed that they achieved the supercooling of a body without external intervention in their thermoelectric experiments, thus arguing that the second law of thermodynamics was bent. Kostic suggested that their claim lacked full comprehension of the second law of thermodynamics. A review of history shows that what Clausius referred to as the second law of thermodynamics is the theorem of the equivalence of transformations (unfairly ignored historically) in a reversible heat–work cycle, rather than "heat can never pass from a cold to a hot body without some other change" that was only viewed by Clausius as a natural phenomenon. Here, we propose the theorem of the equivalence of transformations for reversible thermoelectric cycles. The analysis shows that the supercooling phenomenon Schilling et al. observed is achieved by a reversible combined power–refrigeration cycle. According to the theorem of equivalence of transformations in reversible thermoelectric cycles, the reduction in body temperature to below the ambient temperature requires the body itself to have a higher initial temperature than ambient as compensation. Not only does the supercooling phenomenon not bend the second law, but it provides strong evidence of the second law. [ABSTRACT FROM AUTHOR]

The accurate determination of fracture toughness (KIc) in rock is of great significance to the study of rock fracture characteristics. However, the effect of contact friction in the loading process on the test results of fracture toughness is rarely considered, and the tested KIc in previous studies is generally higher than the inherent KIc of the material. Based on the ABAQUS software, the influence of friction on the test results of KIc was investigated under different material elastic moduli, loading conditions and specimen sizes by the finite element analysis in this study. The results show that for the specimen with the notch semi-circular bend configuration, if the presence of friction is considered, the changes of load level, the span of roller support and the specimen size can significantly affect the test results of fracture toughness, except the elastic modulus of the material; if the influence of friction is not considered, there will be a large deviation in the research results of the size effect of fracture toughness in rock. As the friction coefficient increases, the estimated value of the fracture energy increases, while the fracture process zone length decreases for the specimen with an infinite size. [ABSTRACT FROM AUTHOR]

This article introduces a novel near-field focus (NFF) lens antenna with a three-dimensional (3-D) focus-steering capability operating at terahertz (THz) frequencies. The antenna consists of a pair of thin discrete dielectric lenses (DDLs) placed above a stationary feed horn. First, we demonstrate that the DDL doublet’s in- plane synchronous counter-rotation and co- rotation could scan its focus radially and azimuthally, respectively. A multi-focus synthesis method that compensates the required transmission phases at multi-focus points is developed to further improve its NFF-steering performance. The DDL-based antenna can realize 3-D focus-scanning using a combination of rotation and linear translation mechanisms. The 3-D printing is adopted to fabricate the THz antenna to simplify the manufacturing process and reduce the cost. Both numerical and experimental results demonstrate that the 15 mm-diameter antenna prototype can scan its focus in a 3-D cylindrical space with a diameter of 29 mm and a length of 8 mm at 300 GHz. The proposed 3-D focus-scanning antenna with a large field of view (FoV) of 72° will open new avenues for fast 3-D THz imaging applications. [ABSTRACT FROM AUTHOR]

The ideal gas equation of state (EOS) model is a well-known low-density limiting model. Recently, an ideal dense matter EOS model for the high-density limit symmetric to the ideal gas model has been developed. Here, by mathematically interpolating between the ideal gas and ideal dense matter limiting models, we establish a global model containing two EOS in the form of P-V-T and P-S-T for arbitrary ranges of densities. Different from empirical or semi-empirical EOS, the coefficients in the global EOS have a clear physical meaning and can be determined from a priori knowledge. The proposed global model is thermodynamically consistent and continuous. It reduces to the ideal gas model when approaching the low-density limit and to the ideal dense matter model when approaching the high-density limit. Verifications for 4He show that the global model reproduces the large-range behavior of matter well, along with providing important insight into the nature of the large-range behavior. Compared to the third-order virial EOS and the Benedict–Webb–Rubin EOS, the global P-V-T EOS has higher descriptive accuracy with fewer coefficients over a wide range of data for N2. The global model is shown to work well in extreme applied sciences. It predicts a linear, inverse relationship between entropy and volume when the temperature-to-pressure ratio is constant, which can explain the entropy-production behavior in shock-Hugoniots. [ABSTRACT FROM AUTHOR]

Traffic tunnels are important engineering structures in transportation, and their stability is critical to traffic safety. In particular, when these tunnels are in an earthquake-prone area, the rupture process under seismic excitation needs to be studied in depth for safer tunnel design. In this paper, based on a construction project on the Nairobi-Malaba railway in East Africa, a laboratory shaking table test with 24 working cases of seismic excitation on a mountain tunnel is designed, and the acoustic emission (AE) technique is employed to investigate the tunnel rupture process. The results show that the high frequency components between 20 and 30 kHz of AE signals are the tunnel rupturing signals under the seismic excitation under such conditions. The tunnel vault and the arch foot are prone to rupture during the seismic excitation, and the initial rupture in the arch foot and vault of the tunnel occur under the horizontal and vertical Kobe wave seismic excitation, respectively, with a maximum acceleration of 0.4 g. After the rupture initiation, the tunnel arch foot continues to rupture in the subsequent working cases regardless of whether the excitation direction is horizontal or vertical, while the tunnel vault does not rupture continuously with the implementation of the subsequent excitations. Moreover, the Kobe seismic wave has a higher degree of damage potential to underground structures than the El seismic wave. [ABSTRACT FROM AUTHOR]

The accurate determination of fracture toughness (KIc) in rock is of great significance to the study of rock fracture characteristics. However, the effect of contact friction in the loading process on the test results of fracture toughness is rarely considered, and the tested KIc in previous studies is generally higher than the inherent KIc of the material. Based on the ABAQUS software, the influence of friction on the test results of KIc was investigated under different material elastic moduli, loading conditions and specimen sizes by the finite element analysis in this study. The results show that for the specimen with the notch semi-circular bend configuration, if the presence of friction is considered, the changes of load level, the span of roller support and the specimen size can significantly affect the test results of fracture toughness, except the elastic modulus of the material; if the influence of friction is not considered, there will be a large deviation in the research results of the size effect of fracture toughness in rock. As the friction coefficient increases, the estimated value of the fracture energy increases, while the fracture process zone length decreases for the specimen with an infinite size. [ABSTRACT FROM AUTHOR]

The incidence and disability rate of spinal cord injury (SCI) worldwide are high, imposing a heavy burden on patients. Considerable research efforts have been directed toward identifying new strategies to effectively treat SCI. Governor Vessel electro‐acupuncture (GV‐EA), used in traditional Chinese medicine, combines acupuncture with modern electrical stimulation. It has been shown to improve the microenvironment of injured spinal cord (SC) by increasing levels of endogenous neurotrophic factors and reducing inflammation, thereby protecting injured neurons and promoting myelination. In addition, axons extending from transplanted stem cell‐derived neurons can potentially bridge the two severed ends of tissues in a transected SC to rebuild neuronal circuits and restore motor and sensory functions. However, every single treatment approach to severe SCI has proven unsatisfactory. Combining different treatments—for example, electro‐acupuncture (EA) with adult stem cell transplantation—appears to be a more promising strategy. In this review, we have summarized the recent progress over the past two decades by our team especially in the use of GV‐EA for the repair of SCI. By this strategy, we have shown that EA can stimulate the nerve endings of the meningeal branch. This would elicit the dorsal root ganglion neurons to secrete excess amounts of calcitonin gene‐related peptide centrally in the SC. The neuropeptide then activates the local cells to secrete neurotrophin‐3 (NT‐3), which mediates the survival and differentiation of donor stem cells overexpressing the NT‐3 receptor, at the injury/graft site of the SC. Increased local production of NT‐3 facilitates reconstruction of host neural tissue such as nerve fiber regeneration and myelination. All this events in sequence would ultimately strengthen the cortical motor‐evoked potentials and restore the motor function of paralyzed limbs. The information presented herein provides a basis for future studies on the clinical application of GV‐EA and adult stem cell transplantation for the treatment of SCI. [ABSTRACT FROM AUTHOR]

To realize the hyperstatic performance index of a magnetically suspended flywheel and simultaneously suppress the vibration force caused by mass imbalance and sensor runout, a compound control method based on a repetitive controller and displacement force compensation of the synchronous force is proposed. First, the mechanism of different interference vibration forces is analyzed by establishing a model of the magnetically suspended flywheel. The analysis shows that the x–y direction is symmetric, and the flywheel structure has symmetry. Second, considering the symmetry of the x- and y-directions, the x-direction is taken as an example for analysis, the parameter design and stability analysis are carried out, and the range of parameters of the compound repetitive control method is obtained. Finally, a flywheel with different speeds is simulated. It was found that the vibration force of each frequency can be suppressed by the compound control method, and the inhibition rate of the vibration force can reach as much as 95%. The results show that the unbalanced vibration and vibration force caused by the sensor runout can be effectively suppressed by using the compound repetitive control method. [ABSTRACT FROM AUTHOR]

Accurate load model significantly influences the numerical simulations of power system. The load model obtained by the component‐based method does not adequately reflect the load time‐varying characteristics, and the measurement‐based method relies on fault data, but system faults rarely occur. Inspired by the theory of non‐intrusive load monitoring, the load component decomposition and online modelling method based on the small disturbance response characteristic matching is proposed. An optimization model for the load component decomposition based on the curve fitting of small disturbance response characteristics is established. The construction method of a typical load model library is given and a neural network‐based solution is designed. The proposed method can determine the load components that constitute the synthesis load model and their proportions by only analysing the small disturbance real‐time measurement data. To verify the effectiveness of the proposed method, the distribution of the decomposition errors was analysed by the Monte Carlo simulation. Furthermore, the accuracy of the synthesis load model was verified by a fault simulation using the CEPRI 36‐node system. Experimental results show that the proposed method can provide accurate load compositions and dynamically update the synthesis load model for the online power system simulation, planning and operation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of metal ions on microwave absorption properties of soap was studied. • The larger the metal ion radius, the greater the heating rate. • Divalent metal soap cannot be heated to the goal temperature by absorbing microwaves. • Microwave pyrolysis promotes aromatization and the release of CO, H 2 and CH 4. • The radius of metal ions affects the strengthening effect of microwaves. The pyrolysis of metal soaps to produce hydrocarbon rich fuel has been studied extensively. However, the combined effects of microwave radiation and metal ion types on hydrocarbon production have not been addressed. In this study, the microwave and conventional pyrolysis experiments were conducted on five metal soaps (Li soap, Na soap, K soap, Ca soap, Mg soap). The results demonstrated that the metal ions at the carboxyl end of the soap enhanced the polarity of the reactants, leading to a rapid increase in temperature under microwave conditions. With the ion radius increasing, the heating rate increased gradually. Compared with conventional pyrolysis, microwave pyrolysis exhibited a more rapid heating rate, a higher degree of carbon chain fracture, and a greater abundance of small olefin compounds, which promoted aromatization reaction and the release of CO, H 2 and CH 4. In addition, the composition of the pyrolysis products derived from different metal soaps is affected by the characteristics of metal ions. As the radius of metal ions increased, the oxygen content in the liquid products decreased gradually, while the carbon content increased. The strengthening effect of microwave was further analyzed. With the increase in the radius of metal ions, the strengthening effect of microwaves on olefins formation was gradually weakened, while the inhibiting effect on alkanes formation was gradually enhanced. The structure of carboxylate network is affected by the radius of metal ions, which results in the regular change of the strengthening effect of microwave on olefins and other products. This study is highly significant in guiding the pyrolysis of soapstock waste to prepare olefins and alkanes with high efficiency and low energy consumption. [ABSTRACT FROM AUTHOR]

Oxaliplatin has been included as a basal drug in various chemotherapy regimens for colorectal cancer (CRC), a global health concern. However, acquired resistance to oxaliplatin affects the prognosis. This study aimed to determine whether the consumption of a KD increases the sensitivity of CRC cells to oxaliplatin via the inhibition of a classical stem cell marker, Krupple-like factor 5 (KLF5). KLF5 functions as a transcription factor for the leukemia inhibitory factor (LIF) and directly binds to its promoter region. LIF upregulation induces dephosphorylation of metal regulatory transcription factor 1 (MTF1), which is recruited to the promoter area of Ferroportin (FPN1), the only cellular iron exporter. FPN1 upregulation reduces the labile iron pool (LIP) and ferroptosis in CRC cells. KLF5 knockdown inhibits the LIF/MTF1/FPN1 axis and induces iron overload, thereby conferring sensitivity to oxaliplatin to CRC cells. KD mimicked KLF5 silencing and sensitized CRC cells to oxaliplatin via a similar mechanism. Thus, potential correlations were observed among ketogenesis, stemness, and iron homeostasis. This finding can be used to formulate a new strategy for overcoming oxaliplatin resistance in patients with CRC. • Ketogenic diet sensitizes colorectal cancer to oxaliplatin by inducing ferroptosis. • Ketogenic diet accelerates iron accumulation via the inhibition of KLF5-LIF-FPN1 axis. • Highly-conserved KLF5-LIF transcriptional program is not only functioned as a promoter of cancer stemness, but also a regulator of iron homeostasis. • MTF1 responds to up-regulated LIF and translocates to nuclear inducing FPN1 expression [ABSTRACT FROM AUTHOR]

[Display omitted] Long non-coding RNAs (lncRNAs) have been identified as decisive regulators of liver fibrosis. Hepatic stellate cells (HSCs), major hepatic cells contributing to liver fibrosis, undergo metabolic reprogramming for transdifferentiation and activation maintenance. As a crucial part of metabolic reprogramming, glutaminolysis fuels the tricyclic acid (TCA) cycle that renders HSCs addicted to glutamine. However, how lncRNAs reprogram glutamine metabolism in HSCs is unknown. For this research, we characterized the pro-fibrogenic function of small nucleolar host gene 11 (SNHG11). Our data showed that in carbon tetrachloride (CCl 4 , 7 μL/g, intraperitoneally) treated C57BL/6J mice, SNHG11 expression was highly up-regulated in fibrotic livers and activated primary HSCs. SNHG11 knockdown attenuated the accumulation of fibrotic markers α-SMA and Col1A1 in liver fibrosis tissues and activated HSCs. Western blot and qRT-PCR assays demonstrated that glutaminase (GLS), the rate-limiting enzyme for glutaminolysis, was a downstream target of SNHG11. Furthermore, SNHG11 upregulated glutaminolysis in HSCs through the activation of the Wnt/β-catenin signaling pathway. The results highlighted that SNHG11 is a glutaminolysis-regulated lncRNA that promotes liver fibrosis. A novel insight into the metabolic mechanism that reprograms glutaminolysis in HSCs could be exploited as anti-fibrotic targets. [ABSTRACT FROM AUTHOR]

The prevalences of diabetes mellitus and obesity are increasing yearly and has become a serious social burden. In addition to genetic factors, environmental factors in early life development are critical in influencing the prevalence of metabolic disorders in offspring. A growing body of evidence suggests the critical role of early methyl donor intervention in offspring health. Emerging studies have shown that methyl donors can influence offspring metabolism through epigenetic modifications and changing metabolism-related genes. In this review, we focus on the role of folic acid, betaine, vitamin B12, methionine, and choline in protecting against metabolic disorders in offspring. To address the current evidence on the potential role of maternal methyl donors, we summarize clinical studies as well as experimental animal models that support the impact of maternal methyl donors on offspring metabolism and discuss the mechanisms of action that may bring about these positive effects. Given the worldwide prevalence of metabolic disorders, these findings could be utilized in clinical practice, in which methyl donor supplementation in the early life years may reverse metabolic disorders in offspring and block the harmful intergenerational effect. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive polymers undergo changes under different environmental conditions. Among them, phenylboronic acid (PBA) containing polymers (PBA‐polymers) are unique, because they can selectively react with diols to generate borates that are sensitive to pH, sugars, and H2O2, and can be effectively used to synthesize smart drug carriers and self‐healing hydrogels. Recently, multifunctional PBA‐polymers (MF‐PBA‐polymers) have been developed using multicomponent reactions (MCRs) to introduce PBA groups into polymer structures. These MF‐PBA‐polymers have features similar to those of traditional PBA‐polymers; moreover, they exhibit additional properties, such as fluorescence, antimicrobial activity, and antioxidant capability, when different MCRs are used. In this mini review, the preparation of these MF‐PBA‐polymers are summarized and the new properties/functions that have been introduced into these polymers using different MCRs are discussed. The uses of these MF‐PBA‐polymers as fluorescent cell anticoagulants, drug carriers, and gelators of functional self‐healing hydrogels have been discussed. Additionally, the challenges encountered during their preparation are discussed and also the future developments in this field are touched upon. [ABSTRACT FROM AUTHOR]

Bridgman once reflected on thermodynamics that the laws of thermodynamics were formulated in their present form by the great founders of thermodynamics, Kelvin and Clausius, before all the essential physical facts were in, and there has been no adequate reexamination of the fundamentals since. Thermodynamics still has unknown possibilities waiting to be explored. This paper begins with a brief review of Clausius's work on the second law of thermodynamics and a reassessment of the content of Clausius's statement. The review tells that what Clausius originally referred to as the second law of thermodynamics was, in fact, the theorem of equivalence of transformations (TET) in a reversible cycle. On this basis, a new symmetric form of Clausius's TET is proposed. This theorem says that the two transformations, i.e., the transformation of heat to work and the transformation of work from high pressure to low pressure, should be equivalent in a reversible work-to-heat cycle. New thermodynamic cyclic laws are developed on the basis of the cycle with two work reservoirs (two pressures), which enriches the fundamental of the second law of thermodynamics. [ABSTRACT FROM AUTHOR]

A radar-infrared compatible stealth surface is designed and analyzed. Without modifying the radar absorbing material (RAM), the design can theoretically achieve radar-infrared compatibility and broadband radar absorption through surface patterns and structures. A transmission-line-based model (TLM) is developed to analyze the radar absorbing performance of the surface. Optimization of the structure geometries is conducted aiming to maximize the –10 dB absorption bandwidth in 2–18 GHz. Surface with optimized structure geometries exhibits a superior absorption bandwidth, more than twice the bandwidth of the original 1.5 mm RAM slab, while maintaining a relatively low infrared emissivity. [ABSTRACT FROM AUTHOR]

The self-calibrating sensor based on Tb/Eu-MOF-6 exhibits visual colorimetric sensing for anthrax biomarker: fluorescent color changes from yellow to red after adding DPA. [Display omitted] Bacillus anthracis is toxic bacterial spore that cause human anthrax infections. Therefore, rapid and sensitive detection of Bacillus anthracis or its main biomarker 2, 6-pyridine dicarboxylic acid (DPA) is of great significance. Herein, a series of lanthanide–organic frameworks (Tb/Eu-MOF - 1 – 6) were synthesized by the solvothermal reactions of 2,2′-bipyridine-6,6′-dicarboxylic acid (H 2 BPDC) with Eu3+ and Tb3+. Among these samples, Tb/Eu-MOF-6 exhibited selective detection of DPA with self-calibrating and colorimetric fluorescence determination. The sensitivity of Tb/Eu-MOF-6 revealed a linear response of ln (I N) = -10.896C DPA + 0.14366 with a limit of detection with 4.51 μM. The emission color of Tb/Eu-MOF-6 observed with the naked eye, turned yellow to red after introducing appropriate concentration of DPA. The energy-transfer behavior between BPDC2- Tb3+, and Eu3+ was systematically studied, which primarily controlled the sensitivity of detection. With the combined merits of self-calibrating, rapid and naked-eye recognition of DPA, Tb/Eu-MOF-6 can be counted as a promising contender for anthrax biomarker detection. [ABSTRACT FROM AUTHOR]

The rock mode I fracture characteristics and the size effect are of great significance in understanding the crack initiation, nucleation, propagation, and characterizing the fracture toughness of rocks which is essential for predicting the behavior of rock masses and designing underground structures. In this paper, three-point bending fracture experiments were carried out using single-edge notched beam specimens of different sizes. The fracture characteristics of the entire loading stage, including the post peak stage, were analyzed using digital image correlation (DIC) technology and acoustic emission (AE) technology. Specifically, the calculation of the b value uses the Fisher optimal split and global search algorithm (FGS) method. The results show that both the Fracture process zone (FPZ) length and fracture toughness of granite are size-dependent parameters, and the FPZ length growth rate increases with increasing load level. The failure mode of the source during fracture is mainly tensile failure, and the proportion of tensile failure tends to increase with the increase of specimen size. The temporal b value, average AF value and RA value show corresponding stage changes with time, and the minimum b value, minimum AF value and maximum RA value can characterize the maximum of macroscopic growth rate. • Investigated the size-dependence of post-peak tensile fracture characteristics in granite. • Application of FGS method for calculating acoustic emission b value to analyze the failure scale of specimens. • Tensile failure dominated specimen fractures, with larger specimens showing more tensile failures. • Temporal variations of b value, average frequency, and rise time-to-amplitude ratio reflect changes in corresponding loading stages. [ABSTRACT FROM AUTHOR]

[Display omitted] • The pyrolysis products of different types of waste cooking oil were compared. • The decomposition rate of the ester bond is faster than the fatty acid carbon chain. • Fatty acid composition affects the generation of pyrolysis products. • The degree of deoxidation is related to the raw material H/C eff. • The presence of methoxy is conducive to the formation of benzene and alkyl benzene. In this study, aromatics were prepared by continuous microwave pyrolysis experiment in the presence and absence of HZSM-5 using different types of waste cooking oil (corn oil, rice oil, rapeseed oil, sunflower seed oil, soybean oil, blending oil, peanut oil, palm oil), and the effects of raw material characteristics on pyrolysis products were compared. The results showed that the fatty acid composition of waste cooking oil affects the composition of pyrolysis products. For example, linoleic acid promotes naphthene and inhibits olefin formation; oleic acid is easy to form C 9 and C 10 compounds; compared with oleic acid and linoleic acid, palmitic acid is not conducive to deoxidation. In addition, the deoxidation degree of waste cooking oil is related to the raw material H/C eff , and the order from high to low is corn oil > rapeseed oil > sunflower seed oil > peanut oil > soybean oil. The yield of the oxygen-containing compounds is inversely proportional to it. With the use of HZSM-5 catalyst, the content of toluene and xylene in liquid products is significantly increases, especially the content of xylene. The catalytic effect of rice oil is the most significant, with xylene content increased by 19.2% compared with the non-catalytic pyrolysis. This provides a reference for the efficient treatment of waste oil and the production of aromatics in the future. [ABSTRACT FROM AUTHOR]

Gas field water is the formation water produced together with natural gas in the process of natural gas exploitation. The gas field water treated is difficult to reach the standard due to its wide sources, numerous types and complex composition. In addition, it can pollute soil, surface water and groundwater. In this study, the quality and pollution characteristics of gas field water in eastern Sichuan were studied by conventional water quality determination and GC-MS. The results show that the main components of gas field water in eastern Sichuan were chloride, CODcr, SS, anionic surfactant, sulfide and other substances. The gas field water could be divided into two types according to the characteristics of water quality, of which one had high mineralization and high organic compounds, and the other had high sulfur and high organic compounds. There were 17 kinds of organic pollutants in the gas field water, mainly including alkanes, alcohols, esters and a small amount of acids. [ABSTRACT FROM AUTHOR]

At present, most numerical methods consider the tube walls as the same constant temperature in the simulations of the heat exchanger, and only the external fluid outside the tubes is considered. To investigate the heat transfer performance of the heat exchanger in the real running state, a conjugate heat transfer simulation is performed for a heat exchanger equipped with cross-combined ellipsoidal dimple tubes in this paper. The k-e standard turbulence model is selected to simulate the heating process of tube bank. The distributions of the temperature field and flow field are analyzed carefully. The results indicate that the temperature distribution and the heat flux on the tube wall are uneven, which is different from the case regarding the wall boundaries as a constant temperature. The heat transfer performance of the dimpled tube is higher than that of the smooth tube in the heat exchanger, and the heat transfer performance for aligned arrangement is better than that for staggered arrangement. In addition, the influences of geometric and flowing parameters on heat transfer are discussed. [ABSTRACT FROM AUTHOR]

• We propose a controllable image completion method using CNN and nearest neighbor. • We present a nearest neighbor based pixel matching to improve image quality. • We design a pixel descriptor using multi-scale neural features for pixel matching. • We show that our approach could inpaint damaged paintings with high-frequency content. Ancient paintings are valuable culture legacy which can help archaeologists and culture researchers to study history and humanity. Most ancient artworks have damage problems, such as degradation, flaking and cracking. This work presents a novel controllable image inpainting framework with capability of incorporating suggestions from experts, which can help artists envisage how the ancient painting may have looked after a restoration. The framework leverages the content prediction power of deep convolutional neural network (CNN) and the nearest neighbor based pixel matching, where a deep CNN is designed to produce a coarse estimation of complete paintings by filling in missing regions and nearest neighbor based pixel matching is designed to map a mid-frequency estimation obtained from the deep CNN to high quality outputs in a controllable manner. In addition, we design a pixel descriptor using multi-scale neural features from different layers of a pre-trained deep network to capture different amounts of spatial context. Experimental results demonstrate that the proposed approach successfully predicts information in large missing regions and generates controllable high-frequency photo-realistic inpainting results. [ABSTRACT FROM AUTHOR]

The Middle Route of the South-to-North Water Diversion Project (MR-SNWDP) in China, with construction beginning in 2003, diverts water from Danjiangkou Reservoir to North China for residential, agriculture and industrial use. The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project. In this study, we used Landsat Thematic Mapper (TM) and HJ-1A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area. The changes in land cover were illuminated by transfer matrixes, single dynamic degree, slope zones and fractional vegetation cover (FVC). The results indicated that the area of cropland decreased by 31% and was replaced mainly by shrub over the past 15 years, whereas forest and settlements showed continuous increases of 29.2% and 77.7%, respectively. The changes in cropland were obvious in all slope zones and decreased most remarkably (−43.8%) in the slope zone above 25°. Compared to the FVC of forest and shrub, significant improvement was exhibited in the FVC of grassland, with a growth rate of 16.6%. We concluded that local policies, including economic development, water conservation and immigration resulting from the construction of the MR-SNWDP, were the main drivers of land cover changes; notably, they stimulated the substantial and rapid expansion of settlements, doubled the wetlands and drove the transformation from cropland to settlements in immigration areas. [ABSTRACT FROM AUTHOR]

This article presents a novel design of filtering reflectarray antenna, an integrated module for the combination of filtering and high-gain radiation performance. The filtering reflectarray consists of two-section metal pixel waveguide elements, which can realize the optimized aperture reflection phase distributions in the operating band $f_{1~ \le }f~ _{\le }~f_{2}$ to yield high-gain radiation. Below the lower cutoff frequency $f_{1}$ , the reflection phase distributions drastically deviate from the required ones. Above the upper cutoff frequency $f_{2}$ , both the amplitude and phase distributions fail to provide strong coherent radiation. In the reflectarray synthesis process, a multi-frequency phase matching method (PMM) is further developed, in which the phase compensation for each pixel is implemented at three simultaneous in-band frequencies. Meanwhile, the effects of incident angle for elements are also taken into consideration during the reflectarray synthesis. The design of an $11\lambda \times 11\lambda $ filtering reflectarray operating from 55 to 65 GHz was conveniently fabricated by 3-D printing technology, followed by metal coating with advantages of rapid prototyping, lightweight, and low cost. Both the simulated and measured results show that the proposed reflectarray can realize high-gain radiation within the desired frequency band but presents effective suppression of out-of-band signals, demonstrating its filtering capability. [ABSTRACT FROM AUTHOR]

Persistent idiopathic facial pain is characterized by persistent facial or oral pain in the absence of a neurologic deficit. This underexplored pain may be conducted by various nerves, including cranial nerves and upper cervical spinal roots, and its etiology is unclear. A patient presented with persistent idiopathic facial pain associated with occipital muscle stiffness after an improper neck massage. The patient achieved almost complete pain relief by coblation of right upper cervical nerves (C1 and C2 spinal roots) followed by continuous cervical epidural analgesia for a period of 3 weeks. The analgesic effect was stable during the 3-month follow-up period. Persistent idiopathic facial pain may be cervicogenic, and treatments focusing on cervical spinal roots may provide satisfactory pain control in patients with cervical abnormalities. [ABSTRACT FROM AUTHOR]

A large fraction of the microprocessor energy is consumed by the data movement in the system. One of the reasons is the inefficiency in the conventional cache design. Cache blocks larger than a word are used in conventional caches to exploit spatial locality. However, many applications only use a small part of a cache block before its eviction. Transferring and storing unused data wastes bandwidth, energy, and limited cache space. Prior work on fine-grained caches can reduce data access and storage granularity to reduce the amount of unused data. However, small data blocks typically require greater metadata and control overhead. Sharing the common bits among tags of fine-grained blocks can reduce the metadata overhead but the constraints on which fine-grained blocks can share tag bits can cause fragmentation. This work proposes scrabble, a fine-grained cache that can merge multiple non-contiguous fine-grained blocks into a variable size merged block. The length of the shared tag is maximized to reduce the metadata overhead. The space utilization is improved by supporting merged blocks with variable size. The control overhead can be reduced by moving the merged block together from memory to the last level cache. For applications with poor spatial locality, Scrabble cache can achieve more than 40 percent of performance improvement. Even for application with good spatial locality, the speedup is still more than 7 percent. In general, for an evaluated set of benchmarks, Scrabble cache achieves an average of 2.41× effective capacity over the baseline cache with the same cache capacity which leads to a 16.7 percent performance improvement and an 11 percent on-chip energy reduction. As compared to a state-of-the-art fine-grained cache, Scrabble cache achieves a 1.25× effective capacity, a 7.9 percent speedup, and a 5.8 percent on-chip energy reduction. [ABSTRACT FROM AUTHOR]

In this communication, a chiral squaramide-catalyzed asymmetric dearomative tandem annulation reaction of unmodified Morita–Baylis–Hillman alcohols with azomethine imines has been achieved through a kinetic resolution of MBH alcohols under mild conditions, giving pharmaceutically interesting functionalized hetero-bicyclo[3.3.1]nonane derivatives in good to excellent yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Heat conduction in solids is due to the motion of the phonon gas. A more general description of the heat transport in solids includes consideration of the mass, pressure, and inertial force of the phonon gas. The mass of the phonon gas refers to the equivalent mass of its energy based on Einstein’s mass-energy relation. The thermal vibration of the lattice creates the phonon gas pressure and the momentum change of the phonon gas results in an inertial force. The phonon gas velocity is directly proportional to the heat flux. These concepts are used to establish an equation of motion for the phonon gas including the driving, inertial, and resistant forces using Newtonian dynamics. This equation reduces to Fourier’s law of heat conduction when the inertial force can be neglected relative to the other terms so that heat conduction becomes pure diffusion. However, Fourier’s law of heat conduction no longer holds if the heat flux is very high, such that the inertial force of the phonon gas is not negligible. In such cases, the heat conduction behavior deviates from Fourier’s law even for steady-state conditions so that the heat conduction is characterized by a nonlinear relationship between the heat flux and the temperature gradient. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spatial variations of the toxicological indicators generally resembled PAC levels. • PM 2.5 related to waste treatment facilities exhibited the strongest toxic potencies. • The ROS generation of A549 was highly correlated with MW302 PAHs. • PACs emitted from industrial sources were highly associated with ROS generation. Polycyclic aromatic compounds (PACs) are important toxic organic components in fine particulate matter (PM 2.5), whereas the links between PM 2.5 toxicity and associated PACs in ambient air are poorly understood. This study investigated the spatial–temporal variations of PACs in PM 2.5 collected from 11 sampling sites across a Chinese megacity and characterized the reactive oxygen species (ROS) generation and cytotoxicity induced by organic extracts of PM 2.5 based on cellular assays. The extra trees regression model based on machine learning and ridge regression were used to identify the key toxicants among complex PAC mixtures. The total concentrations of these PACs varied from 2.12 to 71.7 ng/m3 across the study city, and polycyclic aromatic hydrocarbons (PAHs) are the main PACs. The spatial variations of the toxicological indicators generally resembled those of the PAC concentrations, and the PM 2.5 related to waste treatment facilities exhibited the strongest toxic potencies. The ROS generation was highly correlated with high molecular weight PAHs (MW302 PAHs), followed by PAHs with MW<302 amu and oxygenated PAHs, but not with nitrated PAHs and the plastics additives. The cell mortality showed weak correlations with these organic constituents. The associations between the biological endpoints and these PM 2.5 -bound contaminants were further confirmed by exposure to authentic chemicals. Four primary sources of PACs were identified, among which coal and biomass combustion sources (30.2% of the total PACs) and industrial sources (31.0%) were predominant. PACs emitted from industrial sources were highly associated with ROS generation in this city. Our findings highlight the potent ROS-generating potential of MW302 PAHs and the importance of industrial sources contributing to PM 2.5 toxicity in this megacity, raising public concerns and further administration. [ABSTRACT FROM AUTHOR]

In this paper, a novel 3-D printed circularly polarized (CP) modified Fresnel lens antenna operating at 300 GHz is introduced. By virtue of the superior geometric flexibility of the 3-D printing technique, a modified Fresnel lens consisting of subwavelength discrete dielectric posts in the odd-numbered Fresnel zones is proposed. It is further demonstrated that by integrating dielectric anisotropic metamaterial, the modified Fresnel lens can realize CP radiation fed by a simple linearly polarized (LP) open-ended waveguide (OEWG). The 3-D printing approach is also investigated to push the performance envelops of the 3-D printer for realization of the terahertz CP lens. The measured results show that the axial ratios (ARs) of the fabricated antenna prototype are smaller than 3 dB from 265 to 320 GHz. Moreover, the modified Fresnel lens has a maximum gain of 27.4 dBic, which is 0.9 dB larger than that of the conventional Fresnel zone plane antenna (FZPA). These validate the concept, the design, and the fabricated prototype. [ABSTRACT FROM AUTHOR]

Highly‐dense ZrB2–SiC ceramics with excellent mechanical properties including Vickers hardness of 24.5 GPa and fracture toughness of 4.8 MPa/m1/2 were successfully prepared, by spark plasma sintering of the raw powders synthesized by a novel molten‐salt and microwave co‐assisted boro/carbothermal reduction (MSM‐BCTR) method. Compared with the processing conditions required for synthesizing ZrB2–SiC by conventional reduction method, the present MSM‐BCTR method possessed a variety of significant merits including the smaller material cost, lower processing temperature (1200°C), and remarkably higher efficiency (soaking time as short as 20 minutes). More importantly, the ZrB2–SiC powders, resultant from MSM‐BCTR treatment, were verified to have single‐crystalline nature and uniform well‐grown anisotropic morphologies (rod‐like ZrB2 and sheet‐like SiC) as well as great potential in promoting the mechanical properties of their bulk counterparts. This great achievement was mainly ascribed to the specific MSM‐BCTR conditions characterized by microwave heating and molten‐salt medium. [ABSTRACT FROM AUTHOR]

Highlights • Thermostatically controlled loads (TCLs) are used to regional power grid control. • TCLs are modeled as a simplified first-order equivalent thermal parameter model. • A novel TCLs control algorithm is proposed to maximize renewable energy usage. • The algorithm uses the state-queueing model and modified colored power algorithm. • The algorithm considers not only comfort levels but also fairness of customers. Abstract The active development and application of renewable energy, such as wind power and solar power, has become an inevitable tendency, which will promote the increase of the proportion of renewable energy generation accordingly in regional power grids. The intermission and randomness of renewable energy generation lead to enormous challenges in the operation and planning of power systems. One of the current methods to accommodate and reduce renewable energy fluctuation is conventional storage devices, e.g. battery energy storage devices, but this approach has the limitation of a high operating cost, which hinders the technology from popularizing. We present a novel load control algorithm employing the technology of residential thermostatically controlled appliances to maximize renewable energy usage in regional power grids. The thermal dynamics of the thermostatically controlled loads are modeled as a simplified first-order equivalent thermal parameter model. The new load control algorithm, based on the state-queueing model with modified colored power algorithm, is developed to manage activities of residential thermostatically controlled appliances, which allows customers to set different colors as the response levels of their appliances. Such an algorithm can ensure both the comfort level and the fairness of customers. Both a practical case and a real case are applied to demonstrate the effectiveness and practicability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Abstract The bioaccessibility of environmental contaminants has been assessed widely using in vitro simulation; however, the physiological parameters used vary greatly. In this study, we assessed the influence of various physiological parameters and food material on the oral or inhalation bioaccessibility of PM 2.5 -bound hydrophobic organic contaminants (HOCs), including halogenated flame retardants (HFRs), organophosphorus flame retardants (OPFRs), and polycyclic aromatic hydrocarbons (PAHs). The results showed that physiologically based pepsin and pancreatin have a small influence on the HOC liberation from particles. The bioaccessibility increased dramatically when the bile salt concentrations exceeding the critical micelle concentration, and application of porcine bile salts probably lead to underestimated bioaccessibility. Protein and carbohydrates significantly increased the bioaccessibility of most HOCs, while a significant bioaccessibility reduction was caused by green tea. The bioaccessibility of most HOCs was not promoted by liquor under normal physiological condition, but was significantly promoted under fast condition. Long residence time of PM 2.5 in the lung (15 days) would result in higher mobilization of PAHs into the lung fluid than short time (one day). However, the inverse time-dependence for OPFRs suggests degradation in the lung fluid. A mechanism of hydrolysis of organophosphorus ester is hypothesized, and the half lives ranged from 17 to 90 days. Highlights • Pepsin and pancreatin have a small influence on the oral HOC bioaccessibility. • Bioaccessibility increases dramatically when bile salt concentrations exceed CMC. • Green tea leads to a significant reduction in the oral bioaccessibility of HOC. • Bioaccessibility was not significantly promoted by liquor under normal condition. • Degradation of OPFRs in simulated lung fluid was found with half-lives of 17–90 d. [ABSTRACT FROM AUTHOR]