Remarkable progress has been made in surface icephobicity in the recent years. The mainstream standpoint of the reported antiicing surfaces yet only considers the ice–substrate interface and its adjacent regions being of static nature. In reality, the local structures and the overall properties of ice–substrate interfaces evolve with time, temperature and various external stimuli. Understanding the dynamic properties of the icing interface is crucial for shedding new light on the design of new anti‐icing surfaces to meet challenges of harsh conditions including extremely low temperature and/or long working time. This article surveys the state‐of‐the‐art anti‐icing surfaces and dissects their dynamic changes of the chemical/physical states at icing interface. According to the focused critical ice–substrate contacting locations, namely the most important ice–substrate interface and the adjacent regions in the substrate and in the ice, the available anti‐icing surfaces are for the first time re‐assessed by taking the dynamic evolution into account. Subsequently, the recent works in the preparation of dynamic anti‐icing surfaces (DAIS) that consider time‐evolving properties, with their potentials in practical applications, and the challenges confronted are summarized and discussed, aiming for providing a thorough review of the promising concept of DAIS for guiding the future icephobic materials designs. Combating excessive icing through designing and deploying material surfaces has received growing interests. In this review, the practical design principles of anti‐icing surfaces through enabling dynamic changes in the chemical/physical states of the ice/substrate/ice–substrate interface with tailored functions by the three dynamic anti‐icing surfaces categories, namely, surfaces with dynamic substrates, dynamic interfaces, and dynamic ice structure are summarized. As such, enormous interests have been aroused in deploying surfaces that can control icing and mitigate its related damages. The so‐called icephobic or anti‐icing surfaces with properties like repelling incoming water droplets, delaying ice nucleation, repressing ice growth and weakening ice adhesion are designed for anti‐icing purpose. From the early lotus‐leaf inspired superhydrophobic surfaces (SHS) fabricated for repelling water droplets and delaying ice nucleation to the recent omniphobic pitcher‐plants‐inspired slippery liquid‐infused porous surfaces (SLIPS) developed for multiple anti‐icing, there are currently a colorful spectrum of anti‐icing surfaces reported in the literature showing great potentials with practical low ice adhesion strength 0.2–10 kPa  and easy achievable large‐scale ice remove capacity.Icing is one of the most common natural phenomena that greatly impact human activities. Undesired ice formation and accumulation can result in numerous safety problems to aircraft, power grid, transmission line, roadway, marine vessel, renewable energy infrastructure, and many others.7, 8 One of the key characteristics of these surfaces is that the ice–substrate contact area after ice formation is regarded as “constant.” The main focus of surface design lies on the states before ice formation but not the dynamic changes after icing. For instance, the anti‐icing performance of SHS including repelling incoming water and delaying ice nucleation has been widely discussed, with attentions only on the phenomena before ice formation. However, once ice forms on surfaces, especially in icing/deicing cycles, the anti‐icing performance of the SHS decays very fast because the surfaces asperities can be easily damaged. Another commonly used anti‐icing surface SLIPS with lubricant layer atop that enable the surfaces with excellent repellence to any immiscible materials also focus on the surface activities before icing. After ice formation on SLIPS, the lubricants can be exhausted easily due to ice removal. Generally, the static anti‐icing surfaces (SAIS) have disadvantages, for example, inapplicability at extremely low temperature, fragility to surfaces damage and surfaces degradation, and inadaptability to environmental changes.Despite the remarkable progress already made in surface icephobicity in the recent years, the anti‐icing surfaces are generally designed from a static perspective, for instance, texturing the surfaces structures, tuning the modulus of substrates, and modifying the surfaces energy without considering the evolution of properties.24 One These emerging anti‐icing surfaces can be regarded as dynamic anti‐icing surfaces (DAIS), thanks to the integrated evolving properties that can mitigate the interactions between ice and substrate even after ice formation. Extraordinarily, certain effective approaches in the traditional active deicing methodologies were featured in the design of DAIS. Unlike the direct and abrupt application of external mechanical, chemical, and electrical energy as driving force to remove ice, DAIS integrate the active strategies into the evolution of the ice–substrate contacting regions to reduce the resistance of removing ice. For instance, integrating dynamic antifreeze‐secreting capacity into superhydrophobic surfaces to introduce continuous assistance for ice removal even after ice formation. This strategy inherits the advantages of superhydrophobic surfaces in preventing ice forming and triggers evolution of properties at icing region after ice formation for easy ice removal. New anti‐icing surfaces with photothermal traps can actively melt interfacial ice, which utilize solar energy in deicing directly. Importantly, DAIS exhibit improved durability, wider temperature tolerability, and better environment adaptivity, and thus have gained increasing interests in the anti‐icing research and application fields.Very recently, we witness a shift in anti‐icing surface design principles from being of static nature, namely, from no consideration on the changes at the ice–substrate contacting areas after ice formation, to the focus on enabling dynamic changes of the chemical/physical states of the ice/substrate/ice–substrate interface for enhanced anti‐icing performances.40 TheFigure  Surfaces with dynamic properties at the ice–substrate interfaces provide the possibility of altering interface interactions for lowering ice adhesion. Surfaces with dynamic ice are able to direct ice growth, propagation, and even ice melting, which can mitigate ice accumulation and assist ice removal on the surfaces. One can see that DAIS is introduced in this review with the purpose of promoting rethinking of the design principles of new anti‐icing surfaces rather than recategorizing of the known anti‐icing materials. It should be emphasized that the traditional deicing methodologies are still actively in use despite their obvious shortcomings. Under the DAIS concept, the focus is to utilize the evolution of the ice–substrates and its adjacent region in materials design, but not to distinguish active or passive deicing. The following sections detailed the categories of DAIS surfaces.This review aims to provide a thorough survey on the newest development of DAIS. Focusing on the most relevant ice–substrate interfacial regions Figure 1a, and tFigure 44 Sur22.1Figure  Such surface lubricating is driven by the under‐skin disjoining pressure or concentration gradient. The mechanism underling self‐responsive surfaces has inspired the design of anti‐icing surfaces with embedded lubricants in the substrates.Many surfaces exhibit dynamic changes in response to their internal forces. Such self‐responsive surfaces are widely observed in natural organisms and systems. For instance, as shown in Figure 55 Suc Such droplet‐embedded gel system by phase separation of the microscale oil droplet nucleation and formation was metastable, and was able to secrete a lubricating film on the surface with a spreading factor of S = γga – (γla – γgl) > 0, where γga, γla, and γgl are the gel–air, liquid–air, and gel–liquid interfacial tensions, respectively. The surface lubricant layer was regenerable under the driving force of disjoining pressure originated from the van der Waals interactions at the gel surface. Both the thickness of the lubricant layer and the size of the embedded droplets in this substrate were controllable through polymer crosslinking strength and oil content, which offered a strategy for preparing similar substrates for improving anti‐icing performance. Icephobic surfaces following the same strategy for surface regenerable lubricant layers indeed showed ice adhesion strength below 40 kPa, with regenerated lubricating layers after 15 wiping/regenerating tests and long‐term ice adhesion strength below 70 kPa. Through a precise proportioning of polymer and oil, novel self‐lubricating organogels (SLUG) displayed extremely low ice adhesion strength of 0.4 kPa. The ice formed on the SLUG with small tilting angles could slide off at −15 °C, which demonstrated the great potential of self‐responsive substrates in anti‐icing.One notable self‐responsive substrate was developed through phase separation, as shown in Figure 56 Suc For example, alkane embedded in a polymer substrate can diffuse onto the surface driven by the concentration gradient and the internal stress of the polymer matrix, resulting in a solid alkane layer as shown in Figure  Recently, perfluoroalkane wax was verified as a good lubricant candidate for fabricating solid‐lubricant regenerable surfaces. The perfluoroalkane wax regenerating surface demonstrated low ice adhesion strength (≈20 kPa) and high environmental stability. Comparing to the liquid counterpart, solid lubricant layers are mechanically more robust in icing/deicing cycles. For both liquid and solid lubricant regenerable surfaces, the limited regenerating capacity of surfaces hinders their application. Unlike earthworm and poison dart frog that can secrete lubricant from body, the embedded lubricant in the surfaces can be used out easily. Therefore, future studies need to focus on self‐responsible surfaces with long‐term lubricant regenerating capacity.Besides small liquid oil molecules, solid lubricants were also used in self‐responsive substrates for regenerating surface lubricating layers to facilitate ice removal.61 For Such substrates showed significant improvements in mechanical durability because of the self‐healing ability of surface damages at subzero temperature to maintain their smooth topographies  icephobic substrates were prepared by optimizing polymer chain flexibility and concentration of hydrogen bonding, which can restore ≈80% of the ultimate tensile strength of the substrate after healing for 45 min at room temperature. The self‐healing substrates can be promising candidates for robust anti‐icing surfaces in practical environment if the self‐healing functionality is further improved especially at low temperature.Surface damages in practical applications are severely harmful to the icephobicity and durability of anti‐icing surfaces, since any possible interlocking between ice and surface can greatly enhance ice adhesion. Therefore, self‐responsive substrates with self‐healing functionality have been fabricated for anti‐icing purposes.71 Sucs Figure . One of 2.2 By integrating temperature sensitive components during fabrication, anti‐icing substrates can respond to temperature change in the surrounding. One of such substrates incorporated a binary liquid mixture (silicon oil and liquid paraffin) into a PDMS network, and the resulting reversibly thermosecreting organogel (RTS‐organogel) demonstrated distinct morphologies at different temperature, as shown in Figure  Specifically, the substrate was transparent at high temperature as the internal silicon oil and liquid paraffin were miscible. Upon cooling to icing temperature, the substrate secreted visible oil droplet to its surface owing to the collapse of the polymer matrix and the phase separation of the silicon oil from paraffin. Unlike the liquid layer propelled by internal force in the above‐mentioned SLUG shown in Figure  The RTS‐organogel was believed to be more durable than the SLUG, because they could reversibly absorb lubricant into the polymer matrix for replenishing the internal lubricants in storage and against evaporation/contamination.Many anti‐icing surfaces use dynamic substrates that respond to the ambient conditions of temperature, magnetic field, light, and so on.81 By  Interestingly, special temperature responsive lubricants provide a feasible solution to avoid such issue. As shown in Figure  Because the lubricant had a phase transition point from liquid to solid above water freezing point at ≈3 °C, the durability of the fabricated PTSLIPS was greatly improved. The PTSLIPS showed a low ice adhesion strength of ≈4 kPa and long‐term ice adhesion strength of 16 kPa after 30 icing/deicing cycles. Although the PTSLIPS can be fabricated using daily accessible materials like foams and common paper, its anti‐icing performance was superior than the results obtained on other conventional SLIPS used for anti‐icing. Because the phase transition point of the lubricant in the PTSLIPS was only marginally above water freezing temperature, displaced lubricants on the substrate surface in deicing can be restored in the subsequent phase transition cycle of the lubricant at slightly increased temperature, rendering self‐healing abilities and promising application potentials. Furthermore, the solid lubricant can physically prevent water from permeating into the substrate, thus suppressing mechanical interlockings during ice formation on the substrate. It is worth noting here that similar phase change materials (PCMs) were introduced into concrete for anti‐icing. During the phase transition upon cooling, the PCMs released substantial latent heat and hindered ice accumulation in walking pavements. Although the RTS‐organogel and PTSLIPS significantly increase the durability of anti‐icing surfaces, the soft polymer matrices limit their mechanical robustness. Matrices with superior mechanical and chemical resistance should be explored for further improving their durability.Liquid lubricants in anti‐icing substrates can be depleted in limited number of icing/deicing cycles due to the weak interaction between the lubricant and the base materials, which leads to poor durability.32 Int The magnetic slippery surfaces (MAGSS) were the successful representatives of this type of anti‐icing substrates, which used magnetic fluid  along with a magnetic field for controlling surface properties, as shown in Figure  The MAGSS responded to external magnetic field and generated a volumetric force to suppress water droplets from sinking into the substrate body with bulk oil, which led to small water droplet sliding off angle of 2.5°. Remarkably, the MAGSS maintained its liquid‐like phase at low temperature and were highly slippery to ice, showing extremely low ice adhesion strength (≈2 Pa) without degradation after 60 icing/deicing cycles.Magnetic field is currently not often applied in anti‐icing practice. However, utilizing magnetic field as stimuli to modulate substrates has been reported, with encouraging results illustrating the potentials in active deicing technology.80 The By integrating light‐absorbing azobenzene groups into polymer skeleton of the base materials, the so‐called UV responsive substrates (UVRS) were able to utilize UV energy for polymer chain conformation conversion. As shown in Figure 3O4 nanoparticles were infused into porous structures together in fabricating lubricant‐infused surfaces (LIS). Upon irradiation with infrared light, the LIS can absorb optical energy via Fe3O4 nanoparticles, and led to melting of the internal solid cocoa oil as lubricant for surface slippery liquid. The LIS thus possessed switchable hydrophobic/slippery functionality by turning off/on the light source. The smart responses of substrates to magnetic field, UV light and infrared light enhance icephobicity of the surfaces, however, and limit the application scopes of these surfaces at the same time. Novel environmentally responsive substrates which can function under more universal conditions are in demand.Light is another important stimulus source for triggering dynamic changes in anti‐icing substrates.88 By 2.3 Notably, an ultradurable icephobic coating was designed by introducing slide‐ring crosslinkers, namely, molecular pulleys, into PDMS base matrix  on solid surfaces, because ions can greatly impact the structure of water and suppress ice nucleation. Polyelectrolyte brushes hosting ions was employed to probe the effects of counter ions on ice adhesion  had maximum ice adhesion reduction (25–40%) comparing to the bare glass (G) at −18 °C, because of the most negative water structural entropy resulting from strong hydration. In comparison, the polyelectrolyte brushes with chaotropic counterions  did not change the ice adhesion, owing to positive water structural entropy of weak hydration. The nature of the polyelectrolyte layer also affected ice adhesion significantly. For instance, brushes with G‐SO3−Li+ decreased ice adhesion dramatically, which was not observed on samples with G‐COO−Li+. Such results suggested that kosmotropic counterions incorporated with strongly dissociating polyelectrolyte brush could facilitate ice removal. This study provided important reference for integrating counterions for related anti‐icing applications.trimethylammonium chloride)‐Cl (PMETA‐Cl) brush was synthesized on silicon wafers, which can accommodate different ions via ion exchange. Brushes with counterions of Cl−, ClO4−, PF6−, TFSI−, and PFO− were investigated, showing hydrophobicity Cl− < ClO4− < PF6− < TFSI− < PFO−. It was found in the study that ice propagation was efficiently on the highly hydrated PMETA‐Cl and PMETA‐ClO4 brushes, while much longer time were needed for ice form on brushes with counterions of PF6−, TFSI−, and PFO−. Thus, it was assumed that water molecules in the hydrophilic polymer brush (PMETA‐Cl and PMETA‐ClO4) moved toward the ice growth fronts when freezing occurred and consequently promoted ice propagation. By contrast, brushes with PF6−, TFSI−, and PFO− counterions and higher hydrophobicity could result in “water depletion regions,” which reduced the freezable water molecules and suppressed ice propagation /poly (PSS/PAH) and the PSS/poly (PSS/PDAD) coatings were fabricated by tuning the compositions of polyelectrolyte pairs during the layer‐by‐layer deposition. The PDAD had polyelectrolyte interacting more strongly with water in the outmost layer than that in the PAH. Consequently, ice propagation time on the PSS/PAH was two orders of magnitude longer than on the PSS/PDAD with same number of deposition layers. The ice propagation time can be tuned by simply change the composition of the outmost layers, but not by the number of deposition layers. Counterions and their concentration also showed positive effects on ice inhibiting performance on the PEMs. The results indicated that ice propagation was inhibited by depressing the water molecules trapped in the outmost layer of polyelectrolyte coatings. More importantly, the ice growth inhibition properties of PEMs layer in real environment was also investigated in the related studies  placed on the PEMs acting as the artificial ice nuclei, the PSS/PAH samples were still able to delay ice propagated for 2700 s, demonstrating the robustness and wide applicability of their anti‐icing performances. Suppressing ice propagation through counterions is an effective way to avoid rapid frost coverage on whole surfaces comparing to other strategies. However, the ice propagation delaying time still need to be extended for practical usage.To understand the mechanism that control the ice propagation, ice propagation behaviors on polyelectrolyte multilayer (PEM)‐coated surfaces were investigated.52 Thes Figure .[52]4.2 Such phenomenon was caused by the overpressure beneath the droplet originated from fast vaporization and the countering surface adhesion restricting the vapor flow. Because strong vaporization led to high degree of cooling on a supercooled droplet, a rapid recalescence freezing was initiated at the free surface. The latent heat released during the freezing increased the droplet temperature to the equilibrium freezing temperature (0 °C). Under the low‐pressure and low‐humidity conditions, a sudden increase in the vaporization of droplets surfaces resulted in rapid increasing in the overpressure beneath the droplet, which enabled self‐levitation of the droplet when freezing happened. Such phenomenon can be observed on various surfaces with different textures, as shown in Figure Controlling ice growth in a defined pattern on a surface can also be an effective approach to achieve icephobicity, given that ice formation is unavoidable after growth inhibition for a limited period. It was found that water droplets on superhydrophobic surfaces showed spontaneous levitation and trampoline‐like bouncing behavior in a low‐pressure environment.174 Su It was found that the key for self‐dislodging of frozen droplets lied in the freezing orientating process. Specifically, the successful self‐dislodging required free spherical surface of the droplet to be solidified first, forming an ice shell on the external surfaces while maintaining the droplet–substrate contacted region remained liquid. As the subsequent freezing phase boundary moved inward in the droplet asymmetrically, the volume of droplet expanded during the solidification process and caused mass displacement toward the unsolidified droplet–substrate interface. On nonwetting surfaces with pinned ice–liquid–vapor contact line, the displaced mass had no extra space to spread in the final state of solidification and lifted the droplet upward. This dislodging process was observed on various substrates with a wide range of wettability (from hydrophilic to superhydrophobic) and topography, as shown in Figure The freezing‐driven ice‐removal mechanism was further explored on various surfaces.54 It  By depositing silver iodide (AgI) nanoparticles as ice nucleation active sites on surfaces, ice nucleation was controlled to occur concurrently. It was found that the ice crystals on a hydrophilic surface (with water contact angle of 14.5°) possessed an along‐surface growth (ASG) mode. However, the ice on the hydrophobic surface (with water contact angle of 107.3°) exhibited an off‐surface growth (OSG) mode  between ice and its substrate, and subsequently the ice adhesion strength. In the OSG mode, the optimal Acontact was only around 10% of projected area (Aproject). By contrast, the ASG mode resulted in almost full ice contact of the surface project area (Acontact/Aproject ≈ 90%). In ice‐removal tests, the OSG ice was easily blown away by a wind breeze with velocity of 5.78 m s−1 at −3 °C, while the ASG ice remained firmly on the surface. This unique off‐surface growth mode provides alternative ways for assisting surface frost removal, but further investigation is needed for testing on the icephobicity of the surface against larger water drops.By controlling the multicrystal ice growth pattern on exposed surfaces, another important design for novel dynamic ice repellency was also developed recently.13 By 4.3 On surfaces fabricated by assembling poly(poly(ethylene glycol) methyl ether methacrylate)/PDMS (P(PEGMA)/(PDMS)) Janus particles, ice was found to grow into ice crystals/dendrites in certain regions, leaving the other regions dry and clean. The underlying mechanism of the distinct ice growth pattern on the Janus surfaces was elucidated, as depicted in Figure Because the dynamic ice growth patterns are important for anti‐icing, recent investigations further strived to program ice growth on the whole surfaces through surface chemistry/structure deign.178 On On these patterned surfaces, icing was designed to initiate from the polyelectrolyte domains and propagated atop, as shown in Figure  By contrast, ice growth at the ice‐free zone was inhibited. Thus, ice accumulated on the frozen area was accompanied by the consumption of condensed droplets and resulted in the continuous expansion of the ice‐free zones. It was showed in the experiments that the fraction of ice‐free region could be tuned by the grafting density and pattern of polyelectrolyte brushes. By using polyelectrolyte multilayer and polyelectrolyte hydrogel for patterning surfaces, ice‐free regions occupying ≈96% and ≈88% of the total surface area were achieved, respectively.The guided ice growth pattern on Janus surfaces suggested that surface chemistry design could dynamically create ice‐free zone. However, the locations of ice‐free zones on a surface were mostly random. In a recent report, ordered and large scale ice‐free zones taking up ≈96% of the entire surface area were programmed and created on surfaces with patterned polyelectrolyte.177 OnFigure  The unique feature of such surfaces was the introduction of water into microstripes on the surface. Under cooling, the water stripes on the surface froze first, serving as frozen regions. The formation of ice‐free and dry area on the surface followed the same process as discussed above, which led to as high as 90% of the total surface area as dry‐zone (or ice‐free zone). Interestingly, it was found that the growth rate of frost on the ice‐stripes was one order of magnitude lower than that on smooth solids. In short, the prefrozen ice pattern not only protected the other region from icing but also restrained ice propagation.Besides patterning in surface chemistry, microstructures can also be utilized for programming ice‐free zone on surfaces. As shown in Figure 178 Th The microtextures on the artificial leaves resulted in large scale ice‐free area without predesigned water/ice stripes, affecting both water condensation and ice formation on the surface. As water molecules in a supersaturated ambient air diffused more easily to the peaks than to the valleys, the artificial leaves accumulated more and larger droplets on top of its microtexture, where the freezing of droplets initiated at lower temperature. After ice formation on the peaks of the microtextures, the low vapor pressure led to the evaporation of droplets and created stable ice free zones in the valleys, as shown in Figure α, namely, the vertex angle, was proposed to quantitatively correlate to the percentage of ice‐free regions and the microtexture on the surface. The relationship between α and frost coverage was mapped under various ambient humidity, providing significant instructions for constructing ice‐free regions through surface design and structure fabrication. These surfaces with programmed ice‐free zone can be used to protect specific area from icing. Nevertheless, challenges like maintaining the function after surface contaminations and enabling large area of surfaces free from ice in practical application still need to be addressed.Natural surfaces can also program ice formation in winter, namely, ice accumulation on convex veins is more preferred than flat zones. Inspired by such phenomena, artificial leaves with ice‐free regions were designed recently.50 The4.4 Surfaces that can dynamically melt ice were commonly created by integrating materials with thermal effects, including electrothermal, near‐infrared photothermal, magnetothermal, and solar photothermal effects.Ice melting on anti‐icing surfaces is another important aspect of dynamic ice change for avoiding unwanted ice accumulation.181 Su Passive icephobic surfaces, such as superhydrophobic and the SLIPS surfaces, can also integrate active thermal effects for anti‐icing, as introduced in Section 3.2. By enhancing the power density on such surface, ice can be dynamically and constantly melted at the ice–substrate interface until being fully consumed. Recently, a so‐called slippery liquid infused porous electric heating coating (SEHC) was prepared, and contained MWCNTs as electrothermal generators. The SEHC also contained lubricating oil with high thermal conductivity that enabled reduction of ice adhesion strength from 1940 to ≈58 kPa. The obvious advantage of using SEHC instead of superhydrophobic surface was the high thermal conductivity of the infused lubricant, which was nearly one order of magnitude higher than that of air, and thus also enabled higher electrothermal efficiency. With power density of 0.58 W cm−2, ice on SEHC surface was melted completely while ice on superhydrophobic surface was remained . Surfaces with embedded Fe3O4 nanoparticles (0.5 wt%) into the substrate was prepared for melting surface ice. The temperature of such surfaces increased for more than 50 °C in 10 s under irradiation, owing to the excellent near‐infrared thermal response of the Fe3O4 nanoparticles. In an ice‐melting test, the ice layer on the surface can be melted with ambient temperature below −5 °C  increased 13 °C in 5 min.The Fen Figure 20a.[18 Despite the complex design, these surfaces are efficient in ice melting. For instance, superhydrophobic icephobic surfaces with photothermal effects by using cheap candle soot was newly fabricated. Because of the hierarchical structure and the black color, the candle soot has excellent photothermal conversion efficiency. As shown in Figure −2. In a frost‐melting test at −30 °C, the accumulated frost started melting after illuminating 60 s and the surface became free of ice in 720 s, demonstrating superior dynamic ice melting performances. Despite the efficient interface melting even ice melting performance, challenges are remained for the electrothermal and photothermal enhanced surfaces. First, huge thermal input is required to remove vast ice on surfaces. Second, light irradiation is difficult to reach the surface for initiating photothermal effects with heavy snow/ice coverage. Therefore, efforts that can enhance the efficiency of electrothermal/photothermal effects in harsh conditions need to be made.The dynamic ice melting surfaces described above by using electric power, near‐infrared irradiation, and magnetic field were attractive. However, these approaches were partially costly. The photothermal trap surfaces that used solar irradiation energy for ice melting were outstanding candidates and have raised great interests.189 De5Unwanted icing is one of the long‐lasting challenges accompanying mankind in the whole civilization history. It is unfortunate that the most common ways utilized today to combat unwanted icing are still the traditional deicing methodologies involving direct mechanical forces, energy‐intensive thermal treatments or costly chemical handling. Despite that the passive anti‐icing concept has been proposed for more than a decade, automatic ice removal on application scale or at any industrial technology readiness level is still unavailable. Nevertheless, there are significant successes in the anti‐icing materials related researches, especially on the superlow ice adhesion surfaces that enable natural forces for effective ice removal. Although challenges such as durability, anticontamination, functioning at extremely low temperature and harsh conditions need to be addressed, the upscale of such anti‐icing surfaces from laboratory does promise a bright future. In concluding this review, we summarize the dynamic design principles of anti‐icing surfaces through enabling dynamic changes in the chemical/physical states of the ice/substrate/ice–substrate interface with tailored functions by the three DAIS categories, namely, surfaces with dynamic substrates, dynamic interfaces, and dynamic ice.Owing to the abilities of response to stimuli, DAIS with dynamic substrates possess highly appealing potentials. This type of anti‐icing surfaces can utilize various stimuli like temperature, magnetic field, and light for enabling surfaces icephobicity, although not all external stimuli are available in harsh icing situations. For making more practical DAIS in this category, taking the advantages of the intrinsic properties of water and ice for triggering responses of the substrates is the most feasible approach, given that water and ice are always the existing component in the anti‐icing operations. It can be envisioned that novel DIAS with substrates responding sensitively to the interfacial water/ice in cold temperature can provide sensible possibilities in application.DAIS with dynamic interfaces mainly focus on the ice–substrates interaction. To enable dynamic evolution of the interface, the following two pathways are recommended. The first is to enable dynamic change at the interface states, either by generating new interlayers to replace the ice–substrate interfaces or by melting the interface from rigid solid to lubricating liquid. The second is to enable dynamic evolution of the interactions between ice and substrates. This will require better understanding on the fundamental interactions between ice and solid. New interface layers and lubricating layers no doubt have reduced ice–substrates interactions. However, the practical approach of utilizing the intrinsic properties of ice and solids for lowering ice–substrates interactions is still missing. Further investigations that can accelerate such evolutions and apply them for effectively weakening ice adhesion are required.The current DAIS with dynamic ice indicates that ice evolution after formation is not independent from surface properties. Both structures and chemical components of the surfaces can be predesigned for affecting ice propagation, growth and following evolution. It should be noted that both ice growth/propagation inhibitors and programming ice‐free zone cannot make surfaces free of ice. These methods provide alternative choices in specific situations when ice‐free surfaces in confined regions and limited time are required. Dynamic ice melting using solar illumination can be a better choice for outdoor large‐scale anti‐icing applications. However, more studies on the improvement of solar absorption efficiency of these surfaces, especially with ice/snow covering, are still highly essential before these surfaces are ready for practical applications. is relatively low‐cost with abundant materials available, the scale‐up performance still needs further exploration. Furthermore, there is currently no large‐scale demonstration of DAIS available. Extensive studies focusing on scaling up fabrication will speed up transformation of DAIS from laboratory products to practical application.The DAIS also offers alternative pathways for solving the durability problem of icephobic surfaces. Generally, anti‐icing surfaces are designed by modifying the contacts between water/ice and surfaces, for instance, using micro/nanostructured surfaces for depressing water–surface interaction and designing surfaces with low surface energy for weak ice–surface interactions. Such surfaces have poor durability owing to the degradation of the surface topography in usage, because surface nanostructures and chemicals degradation are almost unavoidable in practice. The icephobicity of SAIS commonly suffers from such irreversible decay. There is an unavoidable trade‐off in the performance of SAIS, namely, choosing hard materials for the increase the durability by sacrificing of a decrease in icephobicity or using soft materials for the increase the icephobicity by sacrificing of a decrease in durability. The DAIS pinpoints the importance of evolutions after ice formation in anti‐icing surfaces design. One promising durable icephobicity could be achieved by integrating tough materials/structures with large capacity of abrasion resistance. Such tough materials/structures can provide long‐term durability, while the dynamic components in the surface can weaken ice–substrate interactions and provide excellent icephobicity. More works focus on enabling dynamic functions into robust surfaces and on extending the life spans of dynamic components can promote practical applications of the design of durable icephobic surfaces. There is still a long way for well‐established DAIS approaching large‐scale applications. First, DAIS such as stimuli‐responsive surfaces and photothermal trap surfaces integrate expensive functional components, which significantly increase the cost of large‐scale fabrication. Although alternative methods, such as utilizing PTSLIPS,36 is Given the abundant research results on anti‐icing materials, the understanding of the icing problem also needs to be updated. Regarding ice formation on a surface, it is crucial to realize the dynamic evolution of the interaction between the ice and its substrates. For the practical usage, the surfaces that can maintain long time‐span dynamic properties and can respond to external stimuli are of promising potentials. For instance, ice adhesion on the liquid layer generators and other surfaces that secrete interfacial lubricant can constantly decrease to a negligible level with time. As such, automatic ice removal can be realized even in the outdoor environment if the functionality life‐time of such surfaces is further enhanced. Several anti‐icing surfaces have combined external energy inputs in design. It is fair to say that energy input from solar illumination is one of the most favorable and sustainable choices. Such surfaces still have relatively low power density or suffer from critical environmental limitation such as extremely low temperature, which deserves continuous research effort in the future research. Last but not least, the rational structure–property–function relationship in the current anti‐icing surfaces is still missing. It is certainly difficult to establish this relationship given that approaches to realize surface icephobicity vary greatly as well as a wide variety of materials have been selected for surface fabrication. More theoretical researches on DAIS and new approaches should be promoted, including atomistic modeling and simulation, multiscale approaches, and even machine learning. Based on the current fast evolving status of anti‐icing research, the society can hold an optimistic attitude on unwanted icing and expect practical passive dynamics anti‐icing surfaces in a very near future.The authors declare no conflict of interest.


Lung cancer is the most common cancer and the leading cause of cancer death in the world, accounting for 2.21 million new cases and 1.80 million deaths in 2020.SCLC is classified into two subtypes: neuroendocrine and non‐neuroendocrine. The neuroendocrine subtype shows a classical neuroendocrine morphology and high expression of the transcriptional regulators, such as ASCL1 and NEUROD1. The non‐neuroendocrine subtype shows a mesenchymal morphology and high expression of transcription factors such as c‐Myc, POU2F3, and YAP1, but downregulates ASCL1 and neuroendocrine markers (synaptophysin and chromogranin A).+ T cells.One of the key steps of immunosurveillance is the presentation of peptides on the major histocompatibility complex class I molecules (MHC I) to CD8Cancer Discovery, titled “Intrinsic immunogenicity of small cell lung carcinoma revealed by its cellular plasticity”, Mahadevan et al.high SCLC tumors exhibited a non‐neuroendocrine morphology and had a durable response of immune checkpoint blockade. To further explore the cell state plasticity sufficient to allow conversion between neuroendocrine and non‐neuroendocrine tumor cells and the potential epigenetic mechanism of cellular plasticity in SCLC, the author analyzed the SCLC NCI‐H69 (H69) cells and their non‐neuroendocrine subpopulation (H69M) by H3K27 chromatin immunoprecipitation sequencing (ChIP‐seq) and RNA sequencing (RNA‐seq). They found that depression of TAP1 epigenetic silencing can lead to the transition of SCLC cells from the neuroendocrine state to the non‐neuroendocrine state and the recovery of MHC I‐mediated antigen presentation. Additionally, the results of ChIP‐seq suggest that EZH2 can regulate the epigenetic plasticity of SCLC. Indeed, the following in vitro experiments demonstrated that inhibition of EZH2 promoted the neuroendocrine to non‐neuroendocrine transition, which leads to MHC I recovery. Consistent with these in vitro findings, the authors found that non‐neuroendocrine SCLC tumors were rejected in a syngeneic mouse model, which was manifested by the clonal expansion of CD8+ T cells with immunodominant effectors. Moreover, EZH2 inhibition combined with STING agonism increased the ability of T cells to recognize tumor cells in mice, resulting in the enhancement of SCLC rejection and improvement of overall survival.In recent years, multiplex immunofluorescence (mIF) to simultaneously detect multiple proteins in the same tissue section emerged as very powerful tools to study the cellular and immunologic heterogeneity of tumor.high SCLC subpopulation with intrinsic immunogenicity for the first time and found that this subpopulation had durable response to immune checkpoint blockade. This finding is supported by a recent study on the identification of inflamed SCLC subtypes,+ T cells reactivated by immune checkpoint blockade. Therefore, it is very possible that the expression of MHC I can accurately distinguish those SCLC patients who can develop a durable response to immune checkpoint blockade. Of course, this hypothesis needs larger cohorts of SCLC patients to be verified in the future.This study uncovered a non‐neuroendocrine, MHC I+ cell line and SCLC tissues in this study provided a description of the MHC Ihigh phenotype of SCLC. MHC Ihigh SCLC neither expresses neuroendocrine markers, such as NEUROD1 and ASCL1, nor expresses markers of the non‐neuroendocrine state, such as c‐Myc and YAP1. It highly expresses the epithelial‐mesenchymal transition (EMT) marker AXL. The recently identified inflamed SCLC subtype has similar transcriptional characteristics to the MHC Ihigh subtype: the upregulation of AXL and immune‐associated genes.Additionally, the epigenetic and protein expression profiling of the HLAFurthermore, this study revealed that epigenetic characteristics are major regulators of immunologic plasticity in SCLC as well as TAP1 and STING governs MHC I‐mediated antigen presentation directly. Last but not least, this study explored the rationale for combining EZH2 inhibitors with STING agonists in syngeneic animal models. The regulation of MHC I expression by EZH2 has been reported in SCLC previously.Overall, the most important finding of this study is that EZH2 inhibition can transform neuroendocrine SCLC into an antigenic cell state that is responsive to STING stimulation in vivo. This finding suggests that future clinical studies of SCLC should focus on the combination of EZH2 inhibitors and STING agonists to overcome the inherent immunotherapy resistance of the neuroendocrine state of SCLC. In addition, the identification of non‐neuroendocrine subpopulations in human SCLC through cell state or immunological analysis may also help to stratify patients, which has guiding significance for the formulation of SCLC immunotherapeutic strategies.The author declares no competing interests.


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. A schematic diagram showing that EA stimulates the peripheral nerve endings of the meningeal branch, which transmits information to the SC through nerve fibers of neurons in the DRG. EA can promote the survival and differentiation of transplanted stem cell‐derived neurons or neuron‐like cells in injured SC by inducing the secretion of neurotrophin‐3 by host neurons, which promotes their integration into existing neural circuits. In GV‐EA, a small low‐frequency pulsed current is delivered through needles inserted at the GV acupoints, which ventilates the meridians to promote qi and blood flow.Our previous work has demonstrated that GV‐EA improves the microenvironment of the injured SC and promotes the regeneration of damaged nerve fibers and functional recovery.The transplantation of NSCs into the injured SC is a cell‐based therapy that has been used for more than two decades.Bone marrow mesenchymal stem cells (MSCs)—another type of adult stem cell that can be isolated from a variety of sources—rapidly proliferate in vitro and exhibit multidirectional differentiation potential. When transplanted into the body, MSCs can be induced to differentiate into chondroblasts, osteoblasts, adipocytes, myoblasts, cardiomyocytes, hepatocytes, oligodendrocytes, and neuron‐like cells by factors in the local microenvironment.It is apparent from the literature that there are some critical issues and inherent limitations that need to be fully addressed whether we are to treat SCI more effectively. We consider the following strategies crucial for the better treatment of SCI: (1) to improve the microenvironment of the damaged tissue so it is conducive for the enhancement of nerve regeneration after SCI; (2) to replace the dead neurons, oligodendrocytes, and other major functional cells, and (3) to promote the better integration of replacement functional cells into the original neural network of the SC. Collectively, these factors will eventually help to repair the damaged structure and restore function in the SC. In this review, we summarize the research conducted over the last two decades relating to the therapeutic potential of GV‐EA in combination with adult stem cell transplantation for the repair of the injured SC, paying particular focus upon the data generated by our laboratory.2The application of acupuncture and EA for the treatment of nervous system disorders has become widely accepted over recent years, particularly as the mechanistic basis of their effects have been elucidated.The SC receives direct peripheral sensory input from the trunk and limbs, with peptidergic nerve fibers projecting to the dorsal horn. The fiber endings localized at the acupoints sense the needle and then release peptide substances .In addition, ANXA5 and CRMP2 have been shown to exert protective effects on injured neurons in the SC nucleus dorsalis.3The use of GV‐EA for the treatment of SCI in rats is generally performed at acupuncture points below the spinous processes of the vertebral column corresponding to the upper and lower segments of the injury site  ramus of the spinal nerve of the SC. The acupuncture needle that penetrates the acupoint should pass through the skin, supraspinous ligament, interspinous ligament, and ligamentum flavum. It has been reported that the posterior longitudinal ligament of the vertebral bodies is also innervated by nerve endings of the meningeal branch.To test this hypothesis, we injected red fluorescent cholera toxin B subunit CTB‐555 into the GV acupoint region to mark afferent nerve fibers of the meningeal branch entering the SC across the DRG. Subsequently, we observed CTB‐555 into the GV acupoint region to mark afferent nerve fibers of the meningeal branch entering the SC across the DRG. CTB‐555 labeling was observed along the needle trajectory and in nerve fibers of the meningeal branch in the posterior longitudinal ligaments of the vertebrae. Moreover, CTB‐555‐labeled sensory neurons were observed in the DRG, and sensory afferents labeled with red fluorescence were visible in the dorsal horn in corresponding segments.via afferent nerve fibers of the meningeal branch of the spinal nerve that are distributed at the GV acupoint. Subsequently, we demonstrated unequivocally that GV‐EA can induce the upregulation of CGRP in the DRG cells and its subsequent release at the injury site of SC.GV‐EA increases the expression of CGRP in injured SC tissue; this may be attributable to electrical signals transmitted to the inside of the SC via the afferent nerve fibers of the meningeal branch of the SC.4Following SC transection and demyelination, cells in the injured area and adjacent tissue undergo a number of pathophysiological changes, including the reduced synthesis and secretion of neurotrophic factors; this is one of the main factors underlying the inhibition of nerve repair. An important therapeutic mechanism of GV‐EA in SCI is to induce cells in the SC to synthesize and secrete endogenous neurotrophic factors,NT‐3 is a neurotrophic factor that plays an important role in preventing the death of injured neurons, enhancing neuronal survival and axonal regeneration, and inducing endogenous oligodendrocyte precursor cells to differentiate into mature oligodendrocytes that can restore the myelin sheath.2+ channels (L‐VGCC) and Ca2+ influx; this process activates calcium/calmodulin‐dependent protein kinase (αCaMKII) signaling and the synthesis and secretion of neurotrophic factor .GV‐EA increases the expression of endogenous NT‐3 in the SC, activates NT‐3/TrkC/protein kinase B (AKT) signaling, and enhances TrkC‐overexpressing NSC‐derived neurons of transplanted neural network tissue to promote the establishment of synaptic connections with host neurons that secrete NT‐3.Thus, GV‐EA may directly stimulate the afferent nerve fiber endings of the meningeal branch of the SC in adjacent segments and induce the release of CGRP by DRG neurons into the SC. CGRP acts on spinal neurons expressing receptor activity‐modifying protein (RAMP)1, causing the opening of L‐VGCC, and ultimately leading to the release of NT‐3.It is important to note that following GV‐EA, NT‐3 is not just produced by neurons in the SC; there is evidence that endogenous NT‐3 is also produced by the astrocytes. NT‐3, along with microglia and macrophages may also contribute to the restoration of damaged SC tissue. NT‐3, synthesized and secreted by reactive astrocytes in the rostral and caudal host tissues adjacent to the injury/graft site of SC, may protect the damaged neurons and facilitate axonal regeneration of transplanted NSC‐derived neurons or MSC‐derived neuron‐like cells and host neurons.5Studies have shown that sensory and motor functions are lost below the level of injury following severe SCI.NT‐3 also plays an important role in neuroprotection, axon regeneration, and synaptic plasticity.6Approximately half of all SCIs involve complete SC transection, with little or no remaining nerve tissue in the injured segment. Restoration of SC tissue—for example, through cell transplantation—is essential for the effective treatment of SCI.One way to overcome this problem is to use GV‐EA in combination with NSC transplantation to treat SCI.The NT‐3‐induced activation of intracellular TrkC/AKT signaling is known to promote the differentiation of NSCs into neurons; this process can be blocked by the application of TrkC/AKT inhibitors.in vitro study demonstrated that NT‐3 induces MSCs to overexpress the NT‐3 receptor (TrkC) to differentiate into neuron‐like cells.However, it is important to consider that there are key ethical barriers to NSC transplantation that limit its translational potential. In clinical studies of spinal cord treatment, the embryonic neural stem cells (NSCs) that are used are generally derived from human embryonic brain tissue or human embryonic spinal cord tissue. The ethical debate over whether embryonic NSC technology is “life‐damaging” was triggered by the destruction of embryos caused by selective abortion.TrkC gene‐modified MSCs to treat SCI.TrkC gene‐modified MSCs into neuron‐like cells that can serve as a relay mechanism upon transplantation into a gap in the SC.Based on this observation, we used a combination of GV‐EA and the transplantation of TrkC gene‐modified MSC‐derived cells exhibit electrophysiologic properties in vitro, such as postsynaptic currents and action potentials in the presence of Schwann cells overexpressing NT‐3.Although these transdifferentiated cells are neuron‐like, they express most neuron markers including cytoskeleton proteins ; synaptic structure proteins (postsynaptic density [PSD]‐95 and synaptophysin); neurotransmitters (γ‐aminobutyric acid [GABA] and choline acetyltransferase [ChAT]); and doublecortin (DCX). We have also shown that some of the Collectively, these studies have shown that GV‐EA can improve the microenvironment surrounding the injury/graft area, enhance the survival rate of transplanted neural network tissue cell, and maintain their synaptic connections, thus promoting the functional integration of the donor tissue cells with the SC intrinsic neural circuit. Therefore, under the EA stimulation, the transplanted stem cell‐derived neural network tissue plays a role of preferably restoring SC structure and function as the neuronal relay in the injury/graft area.7Both mechanical and chemical SCI can lead to nerve fiber demyelination.NT‐3 and TrkC activates intracellular signaling pathways that promote the survival and differentiation of oligodendrocyte precursor cells into myelin‐forming cells in the SC.8A large number of studies have investigated the applicability of GV‐EA in the treatment of SCI over the last two decades. Our research has revealed the mechanisms by which GV‐EA can be combined with adult stem cell transplantation to improve the microenvironment of the injured SC to promote the reconstruction of neuronal circuits. In this review, we discussed the multiple effects of GV‐EA, including stimulation of afferent nerve fibers of the meningeal branch of the SC for the transmission of information in the completely transected SC. We also described how GV‐EA can induce NT‐3 synthesis and secretion by cells in the injured SC and enhance the survival, differentiation, and migration of TrkC‐overexpressing NSCs and MSCs transplanted into the injury/graft site and their integration into existing neuronal circuits. We also describe how GV‐EA can assist in the replacement of injured host neurons, improve the microenvironment surrounding the injured tissue, stimulate nerve fiber regeneration and myelination, enhance cortical motor‐evoked potentials, and restore motor function in paralyzed limbs. The current evidence indicates that the combination of GV‐EA and gene‐modified adult stem cell transplantation is an innovative strategy for SCI treatment that warrants further development and testing in clinical settings Figure .Finally, recent advances in genetic engineering techniques and an improved knowledge of gene expression in adult stem cells have led to the demonstration that gene‐modified adult stem cells exhibit stronger therapeutic properties in some disease models compared with wild‐type adult stem cells. For example, a previous study investigated repair in a completely transected SCI and found that if wild‐type adult stem cells were transplanted directly, then the number of differentiated neurons would be smaller and they would not be able to effectively replace neurons that had died due to injury. Hence, gene‐modified adult stem cells may represent a useful option for transplantation to better differentiate into neurons and repair the neural circuits of the host SC. However, there remains an obvious gap between experimental models and clinical trials, along with a host of limitations related to the safety of gene‐modified adult stem cell transplantation for therapeutic use. It would be possible to avoid ethical issues if we were able to transplant another type of stem cell‐human induced pluripotent stem cells (hiPSCs). This is because the preparation of hiPSCs does not involve embryos and germ cells that are harvested from early humans.The authors declare no conflict of interest.Yuan‐shan Zeng was responsible for literature review, investigation, draft preparation and editing; Ying Ding was responsible for literature review and editing; Hao‐yu Xu was responsible for drawing and editing; Xiang Zeng, Bi‐Qin Lai, Ge Li, and Yuan‐Huan Ma were responsible for manuscript review. All authors have read and agreed to the published version of manuscript.


Chest physiotherapy (CPT) is a non‐pharmacological therapy to facilitate airway secretion removal. There have been concerns about potential electromagnetic interference (EMI) and lead integrity problems during the use of vibrating CPT devices in patients with cardiac implantable electronic devices (CIEDs).Two CPT devices can be used safely in patients with CIED.Volunteer patients with CIED underwent device interrogation to check lead integrity and device function before and after application of CPT devices. Mechanical lung vibrator and high‐frequency chest wall oscillation (HFCWO) vests were used while monitoring surface electrocardiograms and intra‐cardiac electrograms.We prospectively enrolled 46 patients with CIEDs . There was no noise detection or EMI during CPT in any patient. None of the patients showed clinically significant changes in lead integrity parameters. HFCWO inappropriately accelerated the pacing rate up to the maximal programmed value in five patients with pacemakers and two with cardiac resynchronization therapy‐defibrillators.CPT may be safely applied to patients with CIED without compromising lead integrity or device function, except for unwanted increase in pacing rate caused by misdetection of chest wall vibration as patients' activity while using HFCWO. Deactivation of the accelerometer‐based activity sensor may be needed when HFCWO is planned for CPT. Various vibrating devices have been used as alternative CPT methods with the expectation of greater time efficiency than standard CPT. Several CPT techniques have been studied to prevent atelectasis leading to pulmonary infection including ventilator‐associated pneumonia.22.1This study was a prospective interventional study. From March 2015 to April 2016, we prospectively enrolled volunteer patients with CIED who had been regularly followed in our hospital. The study incorporated two sequential applications of chest wall vibrating devices for CPT to evaluate the safety of these devices. Eligible patients were those who had (1) a pacemaker due to complete atrio‐ventricular block, (2) an implantable cardioverter‐defibrillator (ICD), or (3) a cardiac resynchronization therapy‐defibrillator (CRT‐D). Patients who met any of the following criteria were excluded: (1) device implantation within 3 months, (2) chest wall problems, including skin infection, burn, or recent rib fracture, or (3) age younger than 19.2.2The study flow is summarized in Figure Two types of vibrating devices were applied sequentially according to a pre‐determined protocol. In the first‐phase, a mechanical lung vibrator  with 60‐Hz vibration frequency was applied to 11 chest wall areas, avoiding CIED generator implantation area (5 on the front and 6 on the back) with two intensities (weak/strong) Figure . It took2.3U test, and categorical data were compared between groups using Fisher's exact test or the χ2 test. The Wilcoxon signed‐rank test was used to compare the lead integrity parameters before and after CPT application. A p‐value < .05 was considered statistically significant.Continuous variables are presented as median and interquartile range, and categorical variables are presented as number and percentage. Continuous variables were compared between groups using the Mann–Whitney 3A total of 46 volunteers was included in the analysis; 25 with pacemakers, 15 with ICDs, and 6 with CRT‐Ds. The baseline characteristics of the study population are presented in Table During the first phase of CPT, the mechanical lung vibrator did not generate any noise or EMI events in any of patients regardless of chest wall area or vibration intensity. There was no significant change in lead integrity parameters or device settings. Similarly, there was no inappropriate detection of noise or EMI during the second phase of CPT with HFCWO. However, the post‐phase 2 CPT device test showed lower atrial sensing amplitude compared to pre‐CPT results. Even though the difference was statistically significant, the numerical difference was so small that there was no requirement for atrial sensitivity adjustment in any patient. There were no significant changes in other lead integrity parameters   impedance at 12‐month was significantly lower compared to those measured after phase 2 CPT and at 6‐month  showed pacing acceleration to the maximal sensor‐driven rates during HFCWO therapy. An example of acceleration in pacing rate is shown in Supplementary figure Figure . There w4In the present study, we prospectively investigated whether CPT with a mechanical vibrator or HFCWO could cause CIED problem including inappropriate detection of EMI or noise, pacing inhibition, lead failure, and device reprogramming. The major findings of this study were: (1) mechanical lung vibrator or HFCWO did not cause EMI or inappropriate noise detection leading to device reprograming or pacing inhibition in complete atrio‐ventricular block patients, (2) lead integrity did not change in a clinically significant way after CPT to require further adjustment of device, and (3) HFCWO inappropriately increased pacing rate in patients whose devices were in rate‐responsive pacing mode.The number of CIED implantations has been steadily increasing every year. It is inevitable that the number of elderly patients with CIEDs will keep growing as the population rapidly ages. Over 80% of pacemaker implantations are performed in the elderly, and a higher number of elderly patients are undergoing CIED implantation than ever before.This prospective interventional study was the first to evaluate the safety of CPT in patients with CIED. It was designed to include different types of CIEDs and CPT devices, so the study results would be applicable to various clinical situations. We simulated different CPT situations with different intensities and locations while monitoring real‐time electrocardiograms and intra‐cardiac electrograms and performed prompt device interrogation after two CPT protocols. This study showed that two different CPT protocols did not induce noise sensing or EMI. There was no problem with mechanical lung vibrator, even when the CPT was applied to the chest wall adjacent to device implantation sites Figure . On the Seven of 12 patients with rate‐responsive pacing mode had an increase in atrial pacing rate to the upper sensor rate caused by unnecessary activation of the accelerometer during HFCWO therapy. Rate‐adaptive pacing was developed to overcome an inherent problem caused by the fixed basal pacing rate. This rate‐responsive pacing mode is known to improve exercise capacity compared to fixed‐rated pacing, particularly in patients with chronotropic incompetence.5There were several limitations to this study. First, this was a single‐center study with a small number of volunteer patients. Second, the study population consisted of people who had no clinical indication for CPT. However, to the best of our knowledge, this is the first prospective interventional study to investigate the safety of CPT in patients with CIED. Because there are lots of variables to consider in real clinical situations, including different application modes of CPT , we made our effort to simulate different CPT situations. We believe our result could be at least a fundamental one for further study to investigate the safety of CPT in patients with CIED. Third, we cannot guarantee the safety of repeated application of CPT in terms of CIED function and lead integrity. It is difficult to determine the presence of lead micro‐dislodgement with only device interrogation. Lastly, caution is needed when applying our results to different forms of CPT or products other than those used in our study.6Chest physiotherapy can be safely used in patients with CIED without compromising lead integrity or device function. Considering inadvertent pacing acceleration caused by false activity sensing of chest wall vibration, physicians need to consider turning off the accelerometer‐based rate modulation function when HFCWO is used.None.Figure S1 Example of pacing rate acceleration during high frequency chest wall oscillation. In a patient with persistent atrial fibrillation and complete atrio‐ventricular block, the pacing rate increased from 60 bpm  (a) to 150 bpm  (b) during high frequency chest wall oscillation therapy.Click here for additional data file.Table S1 Comparison between patients with and without rate‐responsive acceleration of pacing rate during high frequency chest wall oscillation therapyClick here for additional data file.


Daphnia where it is not possible to mark and track individual animals. Here, we present a proof of principle study showing that field cages are a reliable method for collecting individual‐level life‐history data in Daphnia magna. As a first step, we compared the life history of paired animals reared outside and inside cages to test the hypothesis that cages allow free flow of algal food resources. We then used a seminatural mesocosm setting to compare the performance of individual field cages versus glass jars refilled with mesocosm water each day. We found that cages did not inhibit food flow and that differences in life histories between three clones detected in the jar assays were also detectable using the much less labor‐intensive field cages. We conclude that field cages are a feasible approach for collecting individual‐level life‐history data in systems such as Daphnia where individual animals cannot be marked and tracked.Life‐history studies are often conducted in a laboratory environment where it is easy to assay individual animals. However, factors such as temperature, photoperiod, and nutrition vary greatly between laboratory and field environments, making it difficult to compare results. Consequently, there is a need to study individual life histories in the field, but this is currently difficult in systems such as  Daphnia magna. We provide evidence that our cage design allows the collection of realistic, reliable, and repeatable measurements of life‐history data in the natural setting, as animals inside the cages experience the environment in the same way as those outside.There is a need to study individual life histories in the field, but this is currently difficult in systems such as Daphnia where it is not possible to mark and track individual animals. Here, we test the hypothesis that field cages are a useful method for collecting individual‐level life‐history data in  D. magna were kept under standard conditions at 21°C and a 14:10 light:dark photoperiod for two generations in the laboratory before the experiment to reduce any potential maternal effects  as individual field cages. Each cage consisted of a plastic cup‐shaped frame  with sides and base composed of a 170‐μm stainless steel mesh  pipetted inside the cage and swirled gently to allow homogenization of the medium. Experimental containers were exchanged every other day to prevent build‐up of algae along the bases of the cage and beaker. Life‐history data were collected until individuals had dropped their second clutch as described in Plaistow and Collin (D. magna), juvenile growth rate ((length at maturity–length at neonate)/age at maturity), and adult growth rate ((length at second clutch–length at maturity)/(age at second clutch–age at maturity)).The first experiment took place in the laboratory, under controlled conditions of 21°C and a 14:10 light:dark photoperiod using a single h Figure . A singld Collin . Each and Collin . This meLife history trait~Cage treatment+(1|block), to evaluate whether potential differences between caged and uncaged D. magna were caused by strong effects in a few traits or weak effects in many. Residual distributions were evaluated and where the Shapiro–Wilk test showed non‐normal distributions, or the Levene's test indicated heteroscedasticity, boxcox transformations were performed on the data using powerTransform {car}  using two different methods: our individual field cages and a normal glass jar assay similar to that used in the laboratory, where the water in each jar was replaced on a daily basis. To set up the experiment, 10 replicates of each clone were added to individual jars and cages resulting in 60 individuals in total  in March 2019, during which time water temperature fluctuated around 10°C ± 2.5°C and photoperiod increased from 11.5h to 12.8h. We compared the life histories of three Life history trait~Cage treatment*Clone). As above, any data observed to be non‐normal or heteroscedastic were boxcox transformed using powerTransform {car} , smaller size at maturity , and produced slightly smaller offspring . All other traits did not differ between treatments .There was a marginally significant difference in the multivariate phenotype of 3.2p > .3; Table F2,36 = 3.335, p = .047) .Being reared in a field cage or in a jar had no effect on the juvenile growth, size at maturity, and age at maturity across the three tested clones  was actually slightly greater than the volume of media inside the cage (approx. 115 ml), a result of the tapered shape of the cage. Irrespective of what caused the difference in the life histories of animals reared inside and outside cages, the fact that animals on the outside do not do worse than animals on the inside of cages where the food was put each day strongly supports the hypothesis that cages allow the free flow of algae. As a result, our findings support the idea that field cages could be used to quantify individual life histories in wild environments.Daphnia life histories in the wild, we conducted a second experiment where we compared the life history of three D. magna clones from the same population using field cages and a typical laboratory style assay conducted in a seminatural mesocosm. Both approaches allowed us to detect differences in the life histories of the three clones that were the same irrespective of the method used. Moreover, there were no differences in the estimates of mean life‐history traits for each clone measured in jars and in field cages. Therefore, we can conclude that both methods were comparable in their ability to quantify clonal variation in individual level life histories. However, there are a number of reasons why the field cages are preferable to the jar approach. First, there is a significant difference in workload and required visits to the experimental site because jars must be changed every day and cannot be left in the wild for long periods of time. Second, changing jars every day increases disturbance and the requirement to handle and conceivably stress the Daphnia. This can also increase the risk of mortality; we observed that 13 Daphnia died in the jars but only 5 died in the cages. Third, Daphnia kept in jars might experience the same temperature variation and photoperiod, but the individuals being measured are still to some extent isolated from their environment and from dynamic changes occurring throughout the day in factors such as density cues, kairomones, and oxygen. For a jar assay, the dynamism of such cues is constrained by the frequency of the jar changes. While the lack of constant food flux through the day did not affect growth rates at early spring temperatures, nutrient limitation in closed containers is likely to have a greater impact in the summer when temperature‐dependent growth rates reach their maximum.In order to test the hypothesis that field cages are useful for quantifying individual Daphnia do not get to choose where they graze, nor do they get to move vertically in the ponds. Diel vertical migration could however be easily mimicked by moving the cages  between depths in the morning and evening as done by Haupt et al.  that are used to predict population‐level responses to real environmental change from natural environments. Bruijning et al. ; Investigation (lead); Methodology ; Project administration ; Visualization ; Writing‐original draft (lead); Writing‐review & editing . Daniel E. Sadler: Formal analysis ; Investigation ; Visualization ; Writing‐review & editing . Franziska S. Brunner: Formal analysis ; Validation ; Writing‐review & editing . Alan Reynolds: Formal analysis (supporting); Investigation (supporting). Nicola White: Investigation (supporting). Stephen Price: Investigation (supporting); Methodology . Stewart J. Plaistow: Conceptualization (lead); Methodology ; Supervision (lead); Validation ; Writing‐review & editing .


Amid thAfrica is home to the largest number of people living with HIV – two‐thirds of the 38 million people living with HIV reside in on the continent, with 20.7 million people living with HIV in East and southern Africa alone . Many suIn November 2020, we published a call for abstracts for both quantitative and qualitative data on the impact of these adaptations with the intention of drawing attention to the changes made to DSD for HIV in response to COVID‐19. Evidence was needed to understand the effect of the temporary measures being implemented on health outcomes among people living with HIV.Since our call, data have emerged that alleviates some of the initial concern that COVID‐19 would lead to interruptions in HIV treatment delivery and result in considerable increases in morbidity, mortality and HIV incidence . SimilarIn March 2021, WHO launched updated recommendations on service delivery that expand eligibility criteria for access to DSD for HIV treatment, re‐validate recommendations to extend ART refills and clinic visits for those who are established on ART, promote integration of family planning and non‐communicable disease management within HIV programmes and encourage tracing and re‐engagement for those in a treatment interruption . These gThis supplement includes 11 articles from the more than 50 submissions received and addresses many of the areas we highlighted as being of particular interest. In this editorial, we summarize six key themes that emerge from this supplement and what this new data add to our understanding of accelerating access to DSD for HIV before scoping the future for DSD.1. Virtual support on mobile phones can accelerate ART initiation and facilitate monitoring in facilities and communitiesIn response to COVID‐19, many digital platforms were utilized to reduce in‐person delivery of services . Data fr2. DSD for HIV treatment can benefit those recently started on ART and those on second‐line regimensTwo articles within the supplement found non‐inferior HIV‐related health outcomes among populations previously unable to access DSD for HIV treatment. Pooling data from two trials in Lesotho and Zimbabwe, Fatti et al. found that those who were referred to out‐of‐facility DSD models for HIV treatment after only 6–12 months on ART had similar outcomes as compared to those who had been on treatment for a year or longer at the time of referral . Further3. Extended ART refill durations should be a new standard of carePerhaps the most consistent innovation recommended for HIV services during COVID‐19 has been to increase access to and duration of multi‐month dispensing (MMD) of ART refills , 19, 20.4. COVID‐19 has emphasized the importance of expanding access to community‐based servicesData from the scale‐up of DSD for HIV treatment in Nigeria describes enrolment numbers and client health outcomes between 2018–2020 . Of five5.  DSD for HIV is also relevant in more highly resourced settingsData from the United States VA highlight adaptations made in the United States parallel to those seen in less resourced contexts . Adaptat6.  DSD is applicable for HIV prevention and tuberculosis treatmentWhile much of DSD has historically focused on differentiating HIV treatment for those established on treatment, COVID‐19 has also accelerated adaptations to other parts of the HIV care continuum including prevention. In Zimbabwe, Matambanadzo et al. present data on how demand for pre‐exposure prophylaxis (PrEP) among sex workers increased during COVID‐19 lockdowns and was overcome through home delivery, extended PrEP dispensing and support via WhatsApp through providing mobile data and airtime . FurtherMany of the remaining gaps require data from implementation science, such as the paucity of evidence available on the integration of HIV services with other disease areas . FurtherIn summary, the articles in this supplement contribute to a growing evidence base showing that modifications made in response to COVID‐19 should not be temporary, but rather part of a better service delivery system going forward that meets the needs of recipients of care. Indeed, COVID‐19 has quickened acknowledgement across diverse stakeholders that DSD is not just for people who are established on ART. Rather, COVID‐19 has presented an opportunity for a shift toward scale up of self‐care models in general—not just for HIV, but also for tuberculosis, chronic diseases like hypertension and diabetes, and routinely provided services like family planning. The key components of DSD for HIV treatment of reducing the number of clinical visits, separating them from a decreased frequency of drug dispensing and prioritizing out‐of‐facility models apply to all of these purposes. Constraints within many supply chains were compounded by COVID‐19 but should not prevent wider implementation of MMD or DSD models in general.Highlighted in this supplement are the important roles of community‐based services and virtual platforms  in decreasing barriers for accessing critical aspects of the clinical visits as well as the resources required to provide it. These shifts may indeed represent a silver lining to the pandemic—a renewed focus on leveraging improvements in health systems, including supply chain and information technology, to provide high quality person‐centred care.AG is a Deputy Editor of the Journal of the International AIDS Society. PE is an employee of the Bill & Melinda Gates Foundation.All authors were involved in the conceptualization of the article. AG wrote the first draft. All authors approved the final submission.AG's efforts was funded by the Bill & Melinda Gates Foundation INV002610. PE is an employee of the Gates Foundation. IZ is an employee of CIDRZ, with funding from PEPFAR, Bill & Melinda Gates Foundation and the NIH.


Background Endoscopy training has become increasingly emphasized during general surgery residency as reflected by introduction of the Fundamentals of Endoscopic Surgery (FES) examination, which includes testing of skills on virtual reality (VR) simulators. Although studies exist to assess the ability of the simulator to differentiate between novices and experienced endoscopists, it is not well understood how simulators can differentiate skills among resident cohort.Objective To assess the utility of the VR simulator, we evaluated the correlation between resident endoscopy experience and performance on two VR simulator colonoscopy modules on the GI-BRONCH Mentor .Methods Postgraduate years 2 to 5 residents completed “easy” and “difficult” VR colonoscopies, and performance metrics were recorded from October 2017 to February 2018 at Rutgers' two general surgery residency programs. Resident endoscopy experience was obtained through Accreditation Council for Graduate Medical Education case logs. Correlations between resident endoscopy experience and VR colonoscopy performance metrics were assessed using Spearman's rho (ρ) correlation statistic and bivariate logistic regression.Results Fifty-five residents out of 65 (84.6%) eligible participants completed the study. There were limited correlations found between resident endoscopy experience and FES performance metrics and no correlations were found between resident endoscopy experience and binary metrics of colonoscopy—ability to complete colonoscopy, ability to retroflex, and withdrawal time of less than 6 minutes.Conclusion The VR simulator may have a limited ability to discriminate between experience levels among resident cohort. Future studies are needed to further understand how well the VR simulator metrics correlate with resident endoscopy experience. Over the past several years, there has been an increased emphasis placed on the importance of endoscopy during general surgery training. This has been reflected by the Accreditation Council for Graduate Medical Education (ACGME) increasing the number of endoscopy cases required for general surgery trainees as well as the introduction of the American Board of Surgery (ABS) Flexible Endoscopy Curriculum, which culminates in the Fundamentals of Endoscopic Surgery (FES) examination. The ACGME and the ABS utilize resident operative experience as a proxy for procedural competence. As of 2018, the above-mentioned requirements must be met to sit for the general surgery boards.The FES examination consists of a multiple-choice cognitive examination and hands-on skills test.As the FES skills examination is administered on the GI Mentor, there is a theoretical advantage of using this platform to prepare for this examination; it could be used to allow a resident to gauge their readiness to take the examination and practice their skills. One downside is that the specific skills modules tested on the FES examination are not publicly available.To assess the utility of the VR platform, we aimed to evaluate the correlation between resident clinical endoscopy experience and performance on two selected VR colonoscopy modules at two general surgery residency programs. We hypothesized that performance on a simulated colonoscopy would be a poor way to discriminate between experience levels among resident cohort.The resident endoscopy curriculum includes review of the FES online didactic curriculum during the postgraduate years (PGYs) 1 through 5, which was historically complimented by dedicated clinical endoscopy experience from PGY 2 through PGY 5. When the GI Mentor became available on the two Rutgers campuses, New Jersey Medical School (NJMS) and Robert Wood Johnson (RWJ), it was incorporated into the formal simulation curriculum at each general surgery residency training program. After this implementation, these data for this study were collected. Study participation was voluntary, and trainees were offered the same orientation to the simulator regardless of participation. The study took place from October 2017 through February 2018. PGY 2 through PGY 5 categorical residents at NJMS and RWJ general surgery residency programs were eligible for participation. The only exclusion criteria was performing deliberate practice on the simulator prior to study enrollment out of concern that the participants might thoroughly know the simulations, which would be an inaccurate reflection of endoscopic skill. Deliberate practice was identified as those residents who had either already taken the FES examination or used the same modules—the practice modules and/or case modules—to prepare for the examination.not comfortable) to 5 (very comfortable) with performing upper and lower endoscopies, and remark on their prior experience with endoscopy simulators. Upper endoscopy experience was asked to participants as there are data that show a possible correlation between upper and lower endoscopy performances.Participants were asked to complete a survey to provide demographic information, rate their comfort level on a scale of 1  and “difficult”  virtual colonoscopies. They: (1) took a picture of the ileocecal valve, (2) performed a retroflexion maneuver at the end of the procedure and took a picture for the “easy” VR colonoscopy, and (3) did not intubate the terminal ileum. Proctors gave participants 15 minutes to complete each colonoscopy. This 15-minute time limit was chosen to allow for ample time for even novices to complete both cases while considering the time constraints unique to general surgery. Proctors were general surgery residents in a research year and were well oriented to the details of the selected study cases.Participants were tasked with completing the “easy” , percentage of mucosal surface examined (%), time to reach the cecum (seconds), and total time (seconds). The amount of additional time that was spent performing the retroflexion maneuver was included by the simulator in the “total time” metric. Therefore, the metrics dependent on “total time”—calculated withdrawal time and efficiency—would not be accurate and were excluded. Each proctor recorded whether the colonoscopy was completed. Metrics assessed for the “difficult” VR colonoscopy included those of the “easy” VR colonoscopy along with efficiency of screening and withdrawal time. Withdrawal time (seconds) was calculated using the recorded time to cecum and total time metrics. For other binary metrics, the ability to successfully retroflex was assessed for the “easy” VR colonoscopy and having a withdrawal time > 6 minutes—which is commonly cited as a quality indicator for colonoscopyParticipants had their deidentified ACGME case logs downloaded from the secure ACGME Case Log System by the residency program coordinators at each site. All upper and lower endoscopy cases performed up until the date of study participation were counted. Upper endoscopy cases included all diagnostic and/or therapeutic endoscopies of the esophagus, stomach, and/or small bowel. Lower endoscopy cases included all diagnostic and/or therapeutic sigmoidoscopies or colonoscopies.p-value of < 0.05 was considered significant.Descriptive statistics for all variables are reported as counts with percentages for categorical variables and as medians with interquartile ranges for continuous variables. Correlations between clinical endoscopy experience—upper, lower, and total endoscopy cases—and continuous performance metrics were assessed using Spearman's rho (ρ) correlation statistic. The correlations between clinical endoscopy experience and binary performance metrics—the ability to complete a given colonoscopy, retroflex in the “easy” VR colonoscopy, and have a withdrawal time > 6 minutes in the “difficult” VR colonoscopy—were assessed using bivariate logistic regression.SAS software Version 9.4  was used for statistical analysis.Approval from the Institutional Review Board was obtained from both Rutgers sites—RWJ and NJMS.Fifty-five out of 65 possible residents (84.6%) met criteria and completed the study . While p = 0.04). Prior physical simulator use  and right handedness were correlated with a longer withdrawal time.For the “easy” VR colonoscopy, the only significant correlation found was between number of upper endoscopies performed and percentage of mucosa evaluated . HoweveAs one of the largest studies that looked at the correlation of documented resident endoscopy experience with performance on a simulator, our study showed limited correlations between upper, lower, and total endoscopy experience and metrics. Overall, we did not find any correlation with endoscopy experience and the main metrics—completing the colonoscopy, the ability to successfully retroflex, withdrawal time—and most of the FES examination skills. We found that for the “easy” VR colonoscopy, there was a correlation between one's upper endoscopy experience and percentage of mucosa evaluated; several studies have shown a correlation between total endoscopy numbers and this particular metric,Given the correlation between endoscopy experience—upper, lower, and total—and faster time to cecum with the more “difficult” VR colonoscopy and the fact that the critical difference between the two cases was that the “difficult” one was prone to loop formation, this suggests that those with more clinical endoscopy experience are better able to recognize loop formation and/or reduce loops, thus resulting in a faster time to cecum. The metric of efficiency is a combination of time to cecum and percentage of mucosa evaluated; since there was no correlation with endoscopy experience and percentage of mucosa evaluated, this suggests that the correlation between endoscopy experience and efficiency is heavily influenced by the correlation between endoscopy experience and time to cecum. Prior physical model use was correlated with a longer withdrawal time. The reason for this may be an increased familiarity with the expectation to inspect the mucosa carefully for lesions during withdrawal. Although right handedness was correlated with a longer withdrawal time, this finding should be interpreted with caution as there were 51 right-handed versus only 4 left-handed residents.Analysis of our dataset reveals that the number of endoscopy cases completed by our residents showed a right skew, with the majority falling into the 0 to 9 cases category. Part of the reason for this was the reduced number of PGY 5. However, this may be a more realistic distribution of trainee experience. Studies using the GI Mentor test modules showed an ability to distinguish between novices and experienced endoscopists.There were limitations in our study. For one, our study primarily focuses on a limited number of components of validity evidence. According to the most current edition of the American Educational Research Association and American Psychological Association Standards for Educational and Psychological Testing, validity evidence can be broken down into five components: content, response processes, internal structure, relations with other variables, and consequences.Another limitation of our study is that the ACGME case logging system has been shown to be limited by some degree of inaccuracy secondary to underreporting and inaccurate logging of procedures by trainees.A future step would be to further analyze virtual colonoscopy performance within a resident cohort for any potential significant differences with regard to targeting ability—the fifth FES skill that can now be assessed on the simulator.In conclusion, we did not find correlations between resident endoscopy experience and the main metrics of colonoscopy—completion of colonoscopy, the ability to successfully retroflex, and withdrawal time. There were also limited correlations found with resident endoscopy experience and continuous metrics. As the FES examination is used for general surgery residency programs throughout the country, it is imperative to understand the real utility of simulators for surgical training evaluation.