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Cables are critical in engineering structures for load‐bearing, electronic connection, and mechanical transmission. Various cable‐crawling robots (CCRs) have been developed to perform scheduled inspection or convey supplies. Most existing CCRs are often actuated by motors and used in large‐scaled engineering structures. The heavy bodies of these CCRs can cause damage or even casualties once slippage or drop occurs. A small and lightweight CCR that can crawl on thin cables is highly demanded for safety inspection in narrow and confined inner spaces of engineering structures. Herein, a soft CCR (weight, 2.1 g; length, 43 mm) is developed by utilizing multilayered dielectric elastomer actuators. Compared with existing solutions, this CCR achieves crawling on thin cables (diameter: <1 mm) while crawling fastest (horizontal: 0.72 body length per second). The CCR is also capable of transporting objects (horizontal: 3.69 times its own weight; vertical: 0.76 times its own weight), climbing upward on a vertical cable, and locomoting across the water–air interface. The CCR is also demonstrated to crawl on a slack cable and circular/spiral cables. Finally, the soft robot, equipped with an endoscope, demonstrates inspections on a tensegrity structure as well as in an airplane wing model with a preplaced cable. [ABSTRACT FROM AUTHOR]

Free radical polymerization was selected to obtain a promising copolymer scale inhibitor IA‐AM‐SAS with good water solubility and temperature and salt resistance, which is suitable for the treatment of surface pipeline water in oil fields, using itaconic acid (IA), acrylamide (AM), and sodium acrylsulfonate (SAS) as the monomers. The structure of the synthesized copolymer was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. Thermogravimetric results showed that the copolymer does not undergo significant thermal degradation at temperatures below 356°C, indicating that the copolymer has good thermal stability. The molecular weights of the polymers at different monomer ratios were measured using gel permeation chromatography and the relationship between the molecular weights and scale inhibition performance was discussed. The results showed that the scale inhibition effect was best when the monomer molar ratio n(IA): n(AM): n(SAS) was 0.5:2:1.5 and the number of average molecular weight of the prepared copolymer was 7712 g/mol, and the inhibition efficiency of CaCO3 was 84.02% when IA‐AM‐SAS was at a concentration of 30 mg L−1, and the inhibition rate was measured by the standard of static scale inhibition test in the oilfield measured. The range of conditions (PH, Ca2+ concentration, water temperature, and time) of the static scale inhibition test was then expanded using a one‐way controlled variable experiment to explore the performance of IA‐AM‐SAS scale inhibitors under different water quality conditions. The scale inhibition mechanism was explored by scanning electron microscopy, x‐ray diffraction, and x‐ray photoelectron spectroscopy. Briefly, the combination of multiple functional groups enables IA‐AM‐SAS to be applied in complex and challenging environments. [ABSTRACT FROM AUTHOR]

Cephalopod skin is capable of fast color changing enabled by tunable skin transparency as well as structure color. Under this inspiration, herein, a flexible surface with unique hierarchical structure that integrates both transparency change in chemical color (optical scattering) and structure coloration (optical interfering) is developed by harnessing wrinkling instability, thanks to the interfacial Au catalysis in soft lithography. As a result, a hierarchical structure in terms of wrinkled film overlaid by nano‐dome array is obtained in the flexile surface. Experiments find that subject to biaxial strains from 0% to 60%, the hierarchical surface first experiences a transition from nontransparent to transparent owing to the flattening of the wrinkles and then exhibits iridescence structure color shifting from blue to red. The switchable and dynamical tunable mechanochromic characteristics are demonstrated in a smart window, offering potentials for developing flexible devices with optical multiple functionality. [ABSTRACT FROM AUTHOR]

Marine primary producers are largely dependent on and shape the Earth's climate, although their relationship with climate varies over space and time. The growth of phytoplankton and associated marine primary productivity in most of the modern global ocean is limited by the supply of nutrients, including the micronutrient iron. The addition of iron via episodic and frequent events drives the biological carbon pump and promotes the sequestration of atmospheric carbon dioxide (CO2) into the ocean. However, the dependence between iron and marine primary producers adaptively changes over different geological periods due to the variation in global climate and environment. In this review, we examined the role and importance of iron in modulating marine primary production during some specific geological periods, that is, the Great Oxidation Event (GOE) during the Huronian glaciation, the Snowball Earth Event during the Cryogenian, the glacial–interglacial cycles during the Pleistocene, and the period from the last glacial maximum to the late Holocene. Only the change trend of iron bioavailability and climate in the glacial–interglacial cycles is consistent with the Iron Hypothesis. During the GOE and the Snowball Earth periods, although the bioavailability of iron in the ocean and the climate changed dramatically, the changing trend of many factors contradicted the Iron Hypothesis. By detangling the relationship among marine primary productivity, iron availability and oceanic environments in different geological periods, this review can offer some new insights for evaluating the impact of ocean iron fertilization on removing CO2 from the atmosphere and regulating the climate. [ABSTRACT FROM AUTHOR]

The Indian Ocean Dipole (IOD) plays a crucial role in shaping local and global environments, yet its effects on interannual variability of the Arabian Sea oxygen minimum zone (ASOMZ) remains poorly understood. Here, we used a coupled physical‐biogeochemical model to investigate the dynamical response of the ASOMZ to extreme negative (2016) and positive (2019) IOD events. Our findings revealed that the suboxic area of the ASOMZ reduced (expanded) by ∼27% (∼28%) after the negative (positive) IOD event. Compared to the 2019 pIOD event, approximately 2.5 times more oxygen‐rich water was delivered into the Arabian Sea during the 2016 nIOD event, replenishing dissolved oxygen (DO) consumed by intensified upwelling‐induced enhanced remineralization of particulate organic matter (POM), thereby increasing the DO concentration in the Gulf of Aden. Conversely, more POM from the western Arabian Sea was transported to the central Arabian Sea, leading to a subsequent decrease in DO concentration there. Plain Language Summary: The Indian Ocean Dipole (IOD) is a climate phenomenon that sea surface temperature in the western Indian Ocean becomes alternately warmer (positive phase) and then colder (negative phase) than the eastern Indian Ocean south of Indonesia. This variability significantly impacts global atmospheric circulation and environments. The Arabian Sea oxygen minimum zone (ASOMZ) is an area in the Arabian Sea characterized by low dissolved oxygen (DO) levels, which can have adverse effects on marine life. We used a model to examine how extreme IOD events influence the ASOMZ. The results suggested that during the negative IOD event in 2016, the suboxic area of the ASOMZ decreased by approximately 27%, while it expanded by approximately 28% during the positive IOD event in 2019. The response of the ASOMZ to IOD events in the Gulf of Aden was primarily modulated by physical factors, such as the Somali Coastal Current and local upwelling. On the other hand, the ASOMZ in the central Arabian Sea was regulated by a combination of biological and physical processes. These findings contributed to our understanding of the ASOMZ's response to IOD events, which is essential for studying the Arabian Sea's marine ecosystem. Key Points: The response of the Arabian Sea oxygen minimum zone to the Indian Ocean Dipole events in the Gulf of Aden was modulated by physical factorsThe Arabian Sea oxygen minimum zone in the central Arabian Sea was regulated by both biological and physical processesThe upper edge of the Arabian Sea oxygen minimum zone invaded the lower euphotic zone (100–200 m) under the impact of Indian Ocean Dipole events [ABSTRACT FROM AUTHOR]

Ferroptosis as a novel programmed cell death that involves metabolic dysfunction due to iron‐dependent excessive lipid peroxidation has been implicated in atherosclerosis (AS) development characterized by disrupted lipid metabolism, but the atherogenic role of ferroptosis in vascular smooth muscle cells (VSMCs), which are principal components of atherosclerotic plaque fibrous cap, remains unclear. The aim of this study was to determine the effects of ferroptosis on AS induced by lipid overload, and the effects of that on VSMCs ferroptosis. We found intraperitoneal injection of Fer‐1, a ferroptosis inhibitor, ameliorated obviously high‐fat diet‐induced high plasma levels of triglycerides, total cholesterol, low‐density lipoprotein, glucose and atherosclerotic lesions in ApoE−/− mice. Moreover, in vivo and in vitro, Fer‐1 reduced the iron accumulation of atherosclerotic lesions through affecting the expression of TFR1, FTH, and FTL in VSMCs. Interestingly, Fer‐1 did augment nuclear factor E2‐related factor 2/ferroptosis suppressor protein 1 to enhance endogenous resistance to lipid peroxidation, but not classic p53/SCL7A11/GPX4. Those observations indicated inhibition of VSMCs ferroptosis can improve AS lesions independent of p53/SLC7A11/GPX4, which preliminarily revealed the potential mechanism of ferroptosis in aortic VSMCs on AS and provided new therapeutic strategies and targets for AS. [ABSTRACT FROM AUTHOR]

The carbon isotope (δ13C) in marine biogenic carbonate is a valuable tool for comprehending the marine carbon cycle. However, the absence of monthly resolved δ13C records before the instrumental era (since 1850) hinders us to fully understand the global carbon cycle. In this study, we present a δ13C record from a modern Tridacna gigas shell (δ13Cshell) collected from the southern South China Sea (SCS) with an average resolution of ∼10 days. The δ13C record illustrates seasonal and interannual cycles which are superimposed by long‐term decreasing trend. We investigate the environmental controls influencing the δ13Cshell on different time scales. We suggest that more positive δ13Cshell values observed during the juvenile stage (first 8–10 years), which correspond to a high growth rate, can be attributed to 13C enrichment of the internal dissolved inorganic carbon pool. This resulted from the exponential increase of symbiotic zooxanthellae, and preferential 12C sequestration by the accelerated buildup of productive tissues. On the interannual time scale, changes in δ13Cshell were likely affected by both internal (vital effect) and external processes (sea water δ13C), as well as being disturbed by the super El Niño‐La Niña event. Seasonal changes of δ13Cshell were mainly dominated by the intensity of photosynthesis and respiration of symbiotic zooxanthellae, which depend on the seasonal solar irradiance variations in association with precipitation and the South Asian summer monsoon. Our study sheds light on the controlling factors of δ13Cshell variations on seasonal timescale and the long‐term trend, providing insight into the carbon cycle over geological history. Plain Language Summary: Tridacna is a marine bivalve that forms symbiotic zooxanthellae in its mantle tissues and has a hard calcium shell. In this study, we analyzed the carbon isotope composition of the Tridacna shell collected from the southern South China Sea and compared it with various climatic and oceanographic records. Our results suggest that the variability of carbon isotope in the Tridacna shell is predominantly controlled by the activity of its symbiotic zooxanthellae in association with solar radiation and growth rate on various time scales. Furthermore, we found that changes in the carbon isotope of Tridacna shell can be influenced by fluctuations in the South Asian summer monsoon and strong El Niño‐La Niña events. Our study sheds light on the factors that control carbon isotope in the Tridacna shell on different time scales, thereby providing valuable insights into the carbon cycle and climate history. Key Points: A high‐resolution δ13C record of Tridacna shell from the southern South China Sea was presentedActivity and density of symbiotic zooxanthellae linked to the solar irradiance dominated the δ13C changes of Tridacna shellsChanges of δ13C of Tridacna shells are also affected by the South Asian summer monsoon and super El Niño‐La Niña event [ABSTRACT FROM AUTHOR]

A novel low phosphorus terpolymer scale inhibitor P(IA‐MA‐SHP) was prepared by aqueous free radical polymerization using itaconic acid (IA), maleic acid (MA), and sodium hypophosphite (SHP) as raw materials. It was mainly used as an efficient scale inhibitor to inhibit CaCO3. The structures of the copolymers were characterized by Fourier transform infrared, 1H‐NMR, and 13C‐NMR, and the thermal properties, and scale sample crystal structure morphology of the copolymers were analyzed by thermogravimetric analysis, x‐ray diffraction (XRD), and scanning electron microscope (SEM). The effects of dosage, monomer ratio, temperature, and reaction time on the scale inhibition effect were investigated, and the optimal synthesis conditions were determined. The results show that: when the monomer ratio is n(IA):n(MA) = 1.0:1.0, the mass fraction of SHP is 10%, the amount of ammonium persulfate initiator is 12%, the reaction temperature is 90°C, and the reaction time is 4 h, when the dosage of the agent is 20 mg L−1, the scale inhibition rate of CaCO3 is 94.30%, while it also has a favorable inhibitory effect on CaSO4. The results of SEM and XRD show that the copolymer scale inhibitor can distort the lattice and has a favorable adsorption and dispersion effect. In addition, it has a positive effect on controlling the scale. [ABSTRACT FROM AUTHOR]

Soft actuators are favored due to their flexibility and adaptability, but are limited to single actuation mode. Herein, a novel soft actuator with a dual‐kinestate performance is proposed. By subtly integrating a bistable compliant mechanism with artificial muscles, the soft actuator is capable of switching between binary motion and continuous motion with accurate output. Functions of overcoming external interference and regulating the snapping time are realized with programmed voltages. Two applications utilizing the switchable kinestate are illustrated, including a mechanical encryption display system with one actuator and an amplitude modulation system with two actuators in parallel. This novel soft actuator exhibits potential applications for the multi‐mode actuation of soft robots. [ABSTRACT FROM AUTHOR]

Tandem Friedel‐Crafts (FC) and C−H/C−O coupling reactions catalyzed by tris(pentafluorophenyl) borane (B(C6F5)3) were achieved without using any other additive in the absence of solvent. This process can be used for the reactions between a series of dialkylanilines and vinyl ethers with good isolated yields of bis(4‐dialkylaminophenyl) compounds. Based on combined theoretical and experimental studies, the possible reaction mechanism was proposed. B(C6F5)3 can activate the C=C and C−O bond for FC and C−H/C−O coupling reactions respectively. The FC reaction is slow, which is followed by a fast C−H/C−O coupling. [ABSTRACT FROM AUTHOR]

Aim: To assess the electrocardiogram patterns of paced QRS narrowing after successful left bundle branch area pacing (LBBAP) and echocardiographic measurements in patients with bradycardia and bundle branch block (BBB). Methods: We prospectively enrolled 55 consecutive bradycardia patients with BBB and left ventricular ejection fraction ≥40% who had attempted LBBAP. Successful LBBAP was defined as paced QRS morphology of a right BBB (RBBB) pattern in lead V1 and a recording of abruptly shortened and then constant stimulus to peak left ventricular activation time with high and low output. Pacing characteristics and echocardiographic measurements were evaluated perioperatively and at 6‐month follow‐up. Results: The success rate of LBBAP was 83.6% in patients with BBB, and median cumulative X‐ray dose‐area product was 100.5 µGym2 (60.0, 179.3). LBBAP was successful in 19 of 26 patients with left BBB (LBBB) (73.1%) and in 27 of 29 patients with RBBB (93.1%). The QRS duration (QRSd) was significantly shortened in patients with LBBB (QRSd 169.4 ± 22.6 to 119.6 ± 9.5 ms), and five forms of QRSd narrowing were observed in patients with RBBB with the mean QRSd shortened from 143.1 ± 16.6 ms to 119.5 ± 11.7 ms. The thresholds for narrowing of QRSd were higher in RBBB than LBBB (1.74 ± 0.36 V/0.4 ms vs 0.79 ± 0.17 V/0.4 ms, P <.001). During the 6‐month follow‐up, both left and right ventricular synchronies were improved, and narrow QRSd persisted in patients with BBB. Conclusion: In most bradycardia patients, RBBB could be completely or partially narrowed by LBBAP at different pacing models in addition to the correction of LBBB with LBBAP. [ABSTRACT FROM AUTHOR]

Aims: This multicentre observational study aimed to prospectively assess the efficacy of left bundle branch area pacing (LBBAP) in heart failure patients with left bundle branch block (LBBB) and compare the 6‐month outcomes between LBBAP and biventricular pacing (BVP). Methods and results: Consecutive patients with LBBB and left ventricular ejection fraction (LVEF) ≤ 35% were prospectively recruited if they had undergone LBBAP as a primary or rescue strategy from three separate centres from March to December 2018. Patients who received BVP in 2018 were retrospectively selected by using 2 to 1 propensity score matching to minimize bias. Implant characteristics and echocardiographic parameters were assessed during the 6‐month follow‐up. LBBAP procedure succeeded in 81.1% (30/37) of patients, with selective LBBAP in 10 patients, and 3 of 20 patients combined non‐selective LBBAP and LV lead pacing for further QRS narrowing. LBBAP resulted in significant QRS narrowing (from 178.2 ± 18.8 to 121.8 ± 10.8 ms, P < 0.001, paced QRS duration ≤ 130 ms in 27 patients) and improved LVEF (from 28.8 ± 4.5% to 44.3 ± 8.7%, P < 0.001) during the 6‐month follow‐up. The comparison between 27 patients with LBBAP alone and 54 of 130 matching patients with BVP showed that LBBAP delivered a greater reduction in the QRSd (58.0 vs. 12.5 ms, P < 0.001), a greater increase in LVEF (15.6% vs. 7.0%, P < 0.001), and greater echocardiographic (88.9% vs. 66.7%, P = 0.035) and super response (44.4% vs. 16.7%, P = 0.007) to cardiac resynchronization therapy. Conclusions: LBBAP could deliver cardiac resynchronization therapy in most patients with heart failure and LBBB, and might be a promising alternative resynchronization approach to BVP. [ABSTRACT FROM AUTHOR]

Jet propulsion is the main method of locomotion developed by cephalopods to swim through water, either for hunting or escaping from predators. Under this inspiration, diverse underwater robots utilizing jet propulsion‐based locomotion are studied. This article presents a cephalopod‐inspired robot based on a dielectric elastomer actuator, utilizing jet‐propulsion actuation. The actuator is designed and optimized under the guidance of a corresponding electromechanical model. Then, the flow field characteristics of the synthetic jet actuator are simulated and analyzed. Equipped with the actuator, the bioinspired robot can locomote either with a speed of 0.66 body length per second on the surface of the water by jetting air or with a speed of 0.43 body length per second while almost completely submerged underwater by jetting water. The jet actuator presents even more environmental adaptability, which powers dual swimming locomotion by jetting two flow media, and can potentially be applied to the design of underwater robots. [ABSTRACT FROM AUTHOR]

A bias‐compensated normalised least mean square (BCNLMS) algorithm with variable step size (denoted as BCVNLMS) is developed in this work to improve the accuracy and convergence speed for the three‐phase power system (TPPS) frequency estimation in circumstance of the noise and harmonic interference. Taking into account the problem of bias estimation caused by the mixed noises in the acquisition signal of the TPPS, the NLMS algorithm with an unbiased criterion (called BCNLMS) was employed to compensate the bias and improve the estimate accuracy. Furthermore, an adaptive variable step scheme is also incorporated into the BCNLMS algorithm to improve the convergence speed and stability during the process of adaptively frequency estimation. The experimental results show that the proposed BCVNLMS algorithm outperforms other well‐known methods for frequency estimation of the TPPS in several scenarios such as severe noise pollution, harmonic interference and frequency mutation. [ABSTRACT FROM AUTHOR]

Summary: Two novel adaptive filtering algorithms based on the mixed square/fourth error criterion are proposed for solving sparse system identification problems. Motivated by the fact that the proportionate update scheme can enhance the tracking ability of the system, we develop a proportionate least mean square/fourth (PLMS/F) algorithm in this paper. Combining the proportionate update scheme and the LMS/F algorithm, the proposed PLMS/F algorithm shows superiority for non‐Gaussian noise environments. Moreover, to further improve the performance of the PLMS/F algorithm in the noisy input cases, a bias‐compensated PLMS/F algorithm is developed by incorporating an unbiased criterion to compensate the bias caused by input noises. Simulation results in the context of the sparse system identification framework demonstrate that the proposed PLMS/F and bias‐compensated PLMS/F algorithms can achieve excellent identification performance in terms of steady‐state misalignment and convergence speed under noisy input and non‐Gaussian output noise environments. [ABSTRACT FROM AUTHOR]

To address the sparse system identification problem in a non-Gaussian impulsive noise environment, the recursive generalized maximum correntropy criterion (RGMCC) algorithm with sparse penalty constraints is proposed to combat impulsive-inducing instability. Specifically, a recursive algorithm based on the generalized correntropy with a forgetting factor of error is developed to improve the performance of the sparsity aware maximum correntropy criterion algorithms by achieving a robust steady-state error. Considering an unknown sparse system, the l 1-norm and correntropy induced metric are employed in the RGMCC algorithm to exploit sparsity as well as to mitigate impulsive noise simultaneously. Numerical simulations are given to show that the proposed algorithm is robust while providing robust steady-state estimation performance. [ABSTRACT FROM AUTHOR]

ABSTRACT The 2- N-thiosemicarbazide-6-O-hydroxypropyl chitosan (ATU-HPCS) was prepared by chitosan grafted hydroxypropyl and thiosemicarbazide through the method of 'amino protection-graft-deprotection,' while the ATU-HPCS gel membranes were obtained from gelatin and polyvinyl pyrrolidone as additives, and the ATU-HPCS membranes with iodine (ATU-HPCS-I2-M) were prepared by adding the ethanol solution of iodine in the ATU-HPCS gel membranes. The ATU-HPCS-I2-M were characterized to evaluate their potential applications as antibacterial materials. The iodine releasing rule of ATU-HPCS-I2-M showed a sustained-release effect of iodine, the maximum emission was approximately 0.80%. The inhibition zone diameters of ATU-HPCS-I2-M against Staphylococcus aureus (as Gram-positive bacteria) and Escherichia coli (as Gram-negative bacteria) were both greater than 15 mm, it demonstrated significant antibacterial activity compared with the ATU-HPCS gel membranes. The double effects of the biocompatibility of chitosan and the sustained-release of iodine provided an ideal healing environment for wound surface. These properties have made ATU-HPCS-I2-M highly potential as a novel natural macromolecule antimicrobial material preventing the bacteria from burns, surgery wounds, etc. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40535. [ABSTRACT FROM AUTHOR]

ABSTRACT A rapid high-performance liquid chromatographic method was developed and validated for determination of tetrahydropalmatine (THP), an active component of Rhizoma Corydalis, in rat plasma. The samples were prepared using protein precipitation and separated on an Agilent XDB-C18 column (150 × 4.6 mm, 5 µm) with the mobile phase consisting of methanol-0.1% phosphate acid solution, adjusted with triethylamine to pH 5.5 (65:35). Good linearity was found within 0.10-10.00 µg/mL of THP in rat plasma sample. The intra- and inter-day precision values were less than 10%. The developed method was successfully applied to assess the pharmacokinetics of THP in spontaneously hypertensive rats (SHR) and normotensive rats. After oral administration of a single dose of THP (60 mg/kg), the maximum plasma concentrations were 6.15 ± 2.1 and 7.54 ± 2.9 µg/mL for normotensive rats and SHR, respectively. The mean values of AUC0-∞ of THP in SHR were 81.44 ± 45.0 µg h/mL, significantly higher ( p < 0.05) than in normotensive rats (44.06 ± 19.6 µg h/mL). The t1/2 and MRT in SHR were much longer than that in healthy Sprague-Dawley rats, indicating slow elimination of THP in SHR. The results indicated that there are some differences in pharmacokinetics of THP in SHR and Sprague-Dawley rats and it is very important to investigate the pharmacokinetic properties of drugs in pathological conditions. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Pacific North American (PNA) pattern is an internal mode of the Northern Hemisphere atmosphere, which strongly affects the hydroclimate and ecosystems of the Pacific‐North American sector. Recent studies have suggested a more positive PNA pattern in response to greenhouse warming, but how extreme PNA events will change remains unclear. Based on results from the Coupled Model Intercomparison Project Phase 5 multimodel ensemble, we find a 50% increase in the frequency of extreme positive PNA events and a 32% increase in extreme negative PNA events in the 21st century relative to the twentieth century. The increased frequency arises from a shift toward a more positive PNA pattern and is enhanced by more frequent ENSO events under greenhouse warming. Our study suggests that a continued increase in greenhouse‐gas emissions is likely to cause increased occurrence of extreme PNA events, thus increasing the risk of extreme weather and climate in North America. Key Points: Increased frequency of extreme positive and negative PNA events is detected in response to greenhouse warmingIncreased extreme PNA events are associated with a shift toward a positive PNA pattern and more frequent ENSO eventsIncreased extreme PNA occurrences aggravate the risk of weather and climate extremes in North America [ABSTRACT FROM AUTHOR]