Efficacy and safety of robotic versus laparoscopic liver resection for hepatocellular carcinoma: a propensity score-matched retrospective cohort study.

BACKGROUND: Evidence concerning long-term outcome of robotic liver resection (RLR) and laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC) patients is scarce. METHODS: This study enrolled all patients who underwent RLR and LLR for resectable HCC between July 2016 and July 2021. Propensity score matching (PSM) was employed to create a 1:3 match between the RLR and LLR groups. A comprehensive collection and analysis of patient data regarding efficacy and safety have been conducted, along with the evaluation of the learning curve for RLR. RESULTS: Following PSM, a total of 341 patients were included, with 97 in the RLR group and 244 in the LLR group. RLR group demonstrated a significantly longer operative time (median [IQR], 210 [152.0-298.0] min vs. 183.5 [132.3-263.5] min; p = 0.04), with no significant differences in other perioperative and short-term postoperative outcomes. Overall survival (OS) was similar between the two groups (p = 0.43), but RLR group exhibited improved recurrence-free survival (RFS) (median of 65 months vs. 56 months, p = 0.006). The estimated 5-year OS for RLR and LLR were 74.8% (95% CI: 65.4-85.6%) and 80.7% (95% CI: 74.0-88.1%), respectively. The estimated 5-year RFS for RLR and LLR were 58.6% (95% CI: 48.6-70.6%) and 38.3% (95% CI: 26.4-55.9%), respectively. In the multivariate Cox regression analysis, RLR (HR: 0.586, 95% CI (0.393-0.874), p = 0.008) emerged as an independent predictor of reducing recurrence rates and enhanced RFS. The operative learning curve indicates that approximately after the 11th case, the learning curve of RLR stabilized and entered a proficient phase. CONCLUSIONS: OS was comparable between RLR and LLR, and while RFS was improved in the RLR group. RLR demonstrates oncological effectiveness and safety for resectable HCC.

Wireless Gas Sensor Based on the Mesoporous ZnO-SnO2 Heterostructure Enables Ultrasensitive and Rapid Detection of 3-Methylbutyraldehyde.

Achieving ultrasensitive and rapid detection of 3-methylbutyraldehyde is crucial for monitoring chemical intermediate leakage in pharmaceutical and chemical industries as well as diagnosing ventilator-associated pneumonia by monitoring exhaled gas. However, developing a sensitive and rapid method for detecting 3-methylbutyraldehyde poses challenges. Herein, a wireless chemiresistive gas sensor based on a mesoporous ZnO-SnO2 heterostructure is fabricated to enable the ultrasensitive and rapid detection of 3-methylbutyraldehyde for the first time. The mesoporous ZnO-SnO2 heterostructure exhibits a uniform spherical shape (∼79 nm in diameter), a high specific surface area (54.8 m2 g-1), a small crystal size (∼4 nm), and a large pore size (6.7 nm). The gas sensor demonstrates high response (18.98@20 ppm), short response/recovery times (13/13 s), and a low detection limit (0.48 ppm) toward 3-methylbutyraldehyde. Furthermore, a real-time monitoring system is developed utilizing microelectromechanical systems gas sensors. The modification of amorphous ZnO on the mesoporous SnO2 pore wall can effectively increase the chemisorbed oxygen content and the thickness of the electron depletion layer at the gas-solid interface, which facilitates the interface redox reaction and enhances the sensing performance. This work presents an initial example of semiconductor metal oxide gas sensors for efficient detection of 3-methylbutyraldehyde that holds great potential for ensuring safety during chemical production and disease diagnosis.

International consensus guidelines on robotic pancreatic surgery in 2023.

Background: With the rapid development of robotic surgery, especially for the abdominal surgery, robotic pancreatic surgery (RPS) has been applied increasingly around the world. However, evidence-based guidelines regarding its application, safety, and efficacy are still lacking. To harvest robust evidence and comprehensive clinical practice, this study aims to develop international guidelines on the use of RPS. Methods: World Health Organization (WHO) Handbook for Guideline Development, GRADE Grid method, Delphi vote, and the AGREE-II instrument were used to establish the Guideline Steering Group, Guideline Development Group, and Guideline Secretary Group, formulate 19 clinical questions, develop the recommendations, and draft the guidelines. Three online meetings were held on 04/12/2020, 30/11/2021, and 25/01/2022 to vote on the recommendations and get advice and suggestions from all involved experts. All the experts focusing on minimally invasive surgery from America, Europe and Oceania made great contributions to this consensus guideline. Results: After a systematic literature review 176 studies were included, 19 questions were addressed and 14 recommendations were developed through the expert assessment and comprehensive judgment of the quality and credibility of the evidence. Conclusions: The international RPS guidelines can guide current practice for surgeons, patients, medical societies, hospital administrators, and related social communities. Further randomized trials are required to determine the added value of RPS as compared to open and laparoscopic surgery.

3D-printed antibiotic-loaded bone cement spacers as adjunctive therapy for hip periprosthetic infection after arthroplasty: A clinical assessment.

OBJECTIVE: To explore the effect of three-dimensional (3D) printing to create personalized antibiotic-loaded bone cement (ALBC) spacers to assist in treatment of periprosthetic infection after total hip arthroplasty (THA). METHODS: The data of 40 patients with postoperative infection after THA were analysed retrospectively. The patients were divided into two groups: the 3D-printing group (age 47-78 years, n = 20) and the conventional group (age 57-78 years, n = 20). In stage I surgery, 3D-printed silicone moulds were used to create ALBC spacers for the 3D-printing group, while traditional manual methods were used to create spacers for the conventional group. After the infection was controlled, both groups underwent conventional hip revision surgery (stage II surgery). All patients were evaluated using the Harris Hip Score (HHS) (primary outcome) for hip function. RESULTS: All 40 patients had follow-up data from 3 months after stage I surgery and 12 months after stage II surgery. The intergroup difference in HHS was 11.25 points [97.5% confidence interval (CI) 7.92-14.58; P < 0.01] at 3 months after stage I surgery, and 9.15 points (97.5% CI 4.82-13.48; P < 0.01) at 12 months after stage II surgery. The overall difference between the two groups was 9.55 points (97.5% CI 5.83-13.27; P < 0.01), which was significant (P < 0.05). CONCLUSION: During the follow-up period, the hip function of the 3D-printing group was superior to that of the conventional group following the treatment of infections after THA.

Automated diagnosis of pancreatic mucinous and serous cystic neoplasms with modality-fusion deep neural network using multi-modality MRIs.

Background: Pancreatic cystic neoplasms are increasingly diagnosed with the development of medical imaging technology and people's self-care awareness. However, two of their sub-types, serous cystic neoplasms (SCN) and mucinous cystic neoplasms (MCN), are often misclassified from each other. Because SCN is primarily benign and MCN has a high rate of malignant transformation. Distinguishing SCN and MCN is challenging and essential. Purpose: MRIs have many different modalities, complete with SCN and MCN diagnosis information. With the help of an artificial intelligence-based algorithm, we aimed to propose a multi-modal hybrid deep learning network that can efficiently diagnose SCN and MCN using multi-modality MRIs. Methods: A cross-modal feature fusion structure was innovatively designed, combining features of seven modalities to realize the classification of SCN and MCN. 69 Patients with multi-modalities of MRIs were included, and experiments showed performances of every modality. Results: The proposed method with the optimized settings outperformed all other techniques and human radiologists with high accuracy of 75.07% and an AUC of 82.77%. Besides, the proposed disentanglement method outperformed other fusion methods, and delayed contrast-enhanced T1-weighted MRIs proved most valuable in diagnosing SCN and MCN. Conclusions: Through the use of a contemporary artificial intelligence algorithm, physicians can attain high performance in the complex challenge of diagnosing SCN and MCN, surpassing human radiologists to a significant degree.

Polarity Conversion of the Ag2S/AgInS2 Heterojunction by Radical-Induced Positive Feedback Polydopamine Adhesion for Signal-Switchable Photoelectrochemical Biosensing.

Efficient tuning of the polarity of photoactive nanomaterials is of great importance in improving the performance of photoelectrochemical (PEC) sensing platforms. Herein, polarity of the Ag2S/AgInS2 heterojunction is converted by radical-induced positive feedback polydopamine (PDA) adhesion, which is further employed to develop a signal-switchable PEC biosensor. In the nanocomposites, Ag2S and AgInS2 achieve electron-hole separation, exhibiting a strong anodic PEC response. Under the irradiation of light, the Ag2S/AgInS2 heterojunction is able to produce superoxide radical and hydroxyl radical intermediate species, leading to the polymerization of dopamine (DA) and the subsequent adhesion of PDA onto the Ag2S/AgInS2 heterojunction (Ag2S/AgInS2@PDA). By constructing a new electron-transfer pathway with PDA, the polarity of the Ag2S/AgInS2 heterojunction is converted, and the PEC response changes from anodic to cathodic photocurrents. In addition, since the photoreduction activity of PDA is stronger than that of the Ag2S/AgInS2 heterojunction, more superoxide radical can be produced by Ag2S/AgInS2@PDA once PDA is generated, thereby promoting the generation of PDA. Consequently, a positive feedback mechanism is established to enhance the polarity conversion of the Ag2S/AgInS2 heterojunction and amplify the responding to DA. As a result, the bioanalytical method is capable of sensitively quantifying DA in 10 orders of magnitude with an ultralow limit of detection. Moreover, the applicability of this biosensor in real samples is identified by measuring DA in fetal bovine serum and compared with a commercial ELISA method. Overall, this work offers an alternative perspective for adjusting photogenerated carriers of nanomaterials and designing high-performance PEC biosensors.

International experts consensus guidelines on robotic liver resection in 2023.

The robotic liver resection (RLR) has been increasingly applied in recent years and its benefits shown in some aspects owing to the technical advancement of robotic surgical system, however, controversies still exist. Based on the foundation of the previous consensus statement, this new consensus document aimed to update clinical recommendations and provide guidance to improve the outcomes of RLR clinical practice. The guideline steering group and guideline expert group were formed by 29 international experts of liver surgery and evidence-based medicine (EBM). Relevant literature was reviewed and analyzed by the evidence evaluation group. According to the WHO Handbook for Guideline Development, the Guidance Principles of Development and Amendment of the Guidelines for Clinical Diagnosis and Treatment in China 2022, a total of 14 recommendations were generated. Among them were 8 recommendations formulated by the GRADE method, and the remaining 6 recommendations were formulated based on literature review and experts' opinion due to insufficient EBM results. This international experts consensus guideline offered guidance for the safe and effective clinical practice and the research direction of RLR in future.

Shape-Programmable Liquid-Crystalline Polyurethane-Based Multimode Actuators Triggered by Light-Driven Molecular Motors.

In recent years, light-driven soft actuators have been rapidly developed as enablers in the fabrication of artificial robots and biomimetic devices. However, it remains challenging to amplify molecular isomerization to multiple modes of macroscopic actuation with large amplitude and complex motions. Here, a strategy is reported to build a light-responsive liquid-crystalline polyurethane elastomer by phototriggered overcrowded alkene-based molecular motors. A trifunctional molecular motor modified with an ethylene glycol spacer on the rotor and stator functions as a crosslinker and unidirectional stirrer that amplifies molecular motion into macroscopic movement. The shape-programmable polymeric film presents superior mechanical properties and characteristic shape-memory effect. Furthermore, diverse modes of motions including bending, unwinding, and contracting with tunable actuation speed over a wide range are achieved. Such research is hoped to pave a new way for the design of advanced light-responsive soft actuators and robots.

Regulation of RIP1-Mediated necroptosis via necrostatin-1 in periodontitis.

OBJECTIVE: To explore the mechanism of receptor-interacting protein 1 (RIP1)-mediated necroptosis during periodontitis progression. BACKGROUND: RIP3 and mixed lineage kinase domain-like protein (MLKL) have been detected to be upregulated in periodontitis models. Because RIP1 is involved in necroptosis, it might also play a role in the progression of periodontitis. METHODS: An experimental periodontitis model in BALB/c mice was established by inducing oral bacterial infection. Western blotting and immunofluorescence analyses were used to detect RIP1 expression in the periodontal ligament. Porphyromonas gingivalis was used to stimulate L929 and MC3T3-E1. RIP1 was inhibited using small-interfering RNA. Western blotting, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA) analyses were used to detect the effect of necroptosis inhibition on the expression of damage-associated molecular patterns and inflammatory cytokines. Necrostatin-1 (Nec-1) was intraperitoneally injected to inhibit RIP1 expression in mice. Necroptosis activation and inflammatory cytokine expression in periodontal tissue were verified. Tartrate-resistant acid phosphatase staining was applied to observe osteoclasts in the bone tissues of different groups. RESULTS: RIP1-mediated necroptosis was activated in mice with periodontitis. P. gingivalis induced RIP1-mediated necroptosis in L929 and MC3T3-E1 cells. After RIP1 inhibition, the expression levels of high mobility group protein B1 (HMGB1) and inflammatory cytokines were downregulated. After inhibiting RIP1 with Nec-1 in vivo, necroptosis was also inhibited, the expression levels of HMGB1 and inflammatory cytokines were downregulated, and osteoclast counts in the periodontal tissue decreased. CONCLUSION: RIP1-mediated necroptosis plays a role in the pathological process of periodontitis in mice. Nec-1 inhibited necroptosis, alleviated inflammation in periodontal tissue, and reduced bone resorption in periodontitis.

18F-FDG-PET/CT-based deep learning model for fully automated prediction of pathological grading for pancreatic ductal adenocarcinoma before surgery.

BACKGROUND: The determination of pathological grading has a guiding significance for the treatment of pancreatic ductal adenocarcinoma (PDAC) patients. However, there is a lack of an accurate and safe method to obtain pathological grading before surgery. The aim of this study is to develop a deep learning (DL) model based on 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) for a fully automatic prediction of preoperative pathological grading of pancreatic cancer. METHODS: A total of 370 PDAC patients from January 2016 to September 2021 were collected retrospectively. All patients underwent 18F-FDG-PET/CT examination before surgery and obtained pathological results after surgery. A DL model for pancreatic cancer lesion segmentation was first developed using 100 of these cases and applied to the remaining cases to obtain lesion regions. After that, all patients were divided into training set, validation set, and test set according to the ratio of 5:1:1. A predictive model of pancreatic cancer pathological grade was developed using the features computed from the lesion regions obtained by the lesion segmentation model and key clinical characteristics of the patients. Finally, the stability of the model was verified by sevenfold cross-validation. RESULTS: The Dice score of the developed PET/CT-based tumor segmentation model for PDAC was 0.89. The area under curve (AUC) of the PET/CT-based DL model developed on the basis of the segmentation model was 0.74, with an accuracy, sensitivity, and specificity of 0.72, 0.73, and 0.72, respectively. After integrating key clinical data, the AUC of the model improved to 0.77, with its accuracy, sensitivity, and specificity boosted to 0.75, 0.77, and 0.73, respectively. CONCLUSION: To the best of our knowledge, this is the first deep learning model to end-to-end predict the pathological grading of PDAC in a fully automatic manner, which is expected to improve clinical decision-making.

Covalently Attached Slippery Surface Coatings to Reduce Protein Adsorptions on Poly(dimethylsiloxane) Planar Surfaces and 3D Microfluidic Channels.

Silicone elastomers, such as poly(dimethylsiloxane) (PDMS), have a broad range of applications in basic biomedical research and clinical medicine, ranging from the preparation of microfluidic devices for organs-on-chips and ventriculoperitoneal shunts for the treatment of hydrocephalus to implantable neural probes for neuropharmacology. Despite the importance, the protein adsorptions on silicone elastomers in these application environments represent a significant challenge. Surface coatings with slippery lubricants, inspired by the Nepenthes pitcher plants, have recently received much attention for reducing protein adsorptions. Nevertheless, the depletion of the physically infused lubricants limits their broad applications. In this study, we report a covalently attached slippery surface coating to reduce protein adsorptions on PDMS surfaces. As demonstrations, we show that the adsorption of serum proteins, human fibrinogen and albumin, can be significantly reduced by the slippery surface coating in both planar PDMS surfaces and 3D microfluidic channels. The preparation of slippery surface coatings relies on the acid-catalyzed polycondensation reaction of dimethyldimethoxysilane, which utilizes a low-cost and scalable dip-coating method. Furthermore, cell metabolic activity and viability studies demonstrate the biocompatibility of the surface coating. These results suggest the potential applications of slippery surface coatings to reduce protein adsorptions for implantable medical devices, organs-on-chips, and many others.

Biosensor integrated tissue chips and their applications on Earth and in space.

The development of space exploration technologies has positively impacted everyday life on Earth in terms of communication, environmental, social, and economic perspectives. The human body constantly fluctuates during spaceflight, even for a short-term mission. Unfortunately, technology is evolving faster than humans' ability to adapt, and many therapeutics entering clinical trials fail even after being subjected to vigorous in vivo testing due to toxicity and lack of efficacy. Therefore, tissue chips (also mentioned as organ-on-a-chip) with biosensors are being developed to compensate for the lack of relevant models to help improve the drug development process. There has been a push to monitor cell and tissue functions, based on their biological signals and utilize the integration of biosensors into tissue chips in space to monitor and assess cell microenvironment in real-time. With the collaboration between the Center for the Advancement of Science in Space (CASIS), the National Aeronautics and Space Administration (NASA) and other partners, they are providing the opportunities to study the effects of microgravity environment has on the human body. Institutions such as the National Institute of Health (NIH) and National Science Foundation (NSF) are partnering with CASIS and NASA to utilize tissue chips onboard the International Space Station (ISS). This article reviews the endless benefits of space technology, the development of integrated biosensors in tissue chips and their applications to better understand human biology, physiology, and diseases in space and on Earth, followed by future perspectives of tissue chip applications on Earth and in space.

A significant other: Non-canonical caspase-4/5/11 inflammasome in periodontitis.

Periodontitis is an oral inflammatory disease characterised by the destruction of periodontal soft tissue and alveolar bone resorption, mainly triggered by plaque microbial infection. Pyroptosis is an inflammatory form of programmed cell death mediated by the pore-forming gasdermin proteins, which resist the invasion of pathogens into the body's immune system. Many studies have found that pyroptosis is closely related to the occurrence and development of periodontitis. At present, most of these studies focused on the canonical pathway mediated by caspase-1. Moreover, Gram-negative bacteria's lipopolysaccharide has been shown to activate a new form of the non-canonical inflammasome by directly binding to human caspase-4/5 and mouse caspase-11 in the cytosol. However, most of the functions of non-canonical inflammasome are still gradually being studied. Therefore, in this review, we have summarised and analysed the existence and regulation mechanism of the non-canonical inflammasome in periodontitis.

Studying the Inflammatory Responses to Amyloid Beta Oligomers in Brain-Specific Pericyte and Endothelial Co-culture from Human Stem Cells.

Background: Recently, the in vitro blood brain barrier (BBB) models derived from human pluripotent stem cells have been given extensive attention in therapeutics due to the implications it has with the health of the central nervous system. It is essential to create an accurate BBB model in vitro in order to better understand the properties of the BBB and how it can respond to inflammatory stimulation and be passed by targeted or non-targeted cell therapeutics, more specifically extracellular vesicles. Methods: Brain-specific pericytes (iPCs) were differentiated from iPSK3 cells using dual SMAD signaling inhibitors and Wnt activation plus fibroblast growth factor 2 (FGF-2). The derived cells were characterized by immunostaining, flow cytometry and RT-PCR. In parallel, blood vessels organoids were derived using Wnt activation, BMP4, FGF2, VEGF and SB431542. The organoids were replated and treated with retinoic acid to enhance the blood brain barrier (BBB) features in the differentiated brain endothelial cells (iECs). Co-culture was performed for the iPCs and iECs in transwell system and 3-D microfluidics channels. Results: The derived iPCs expressed common markers PDGFRb and NG2, as well as brain-specific genes FOXF2, ABCC9, KCNJ8, and ZIC1. The derived iECs expressed common endothelial cell markers CD31, VE-cadherin, as well as BBB-associated genes BRCP, GLUT-1, PGP, ABCC1, OCLN, SLC2A1. The co-culture of the two cell types responded to the stimulation of amyloid ß42 oligomers by the upregulation of expression of TNFa, IL6, NFKB, Casp3, SOD2 and TP53. The co-culture also showed the property of trans-endothelial electrical resistance. The proof-of-concept vascularization strategy was demonstrated in a 3-D microfluidics-based device. Conclusion: The derived iPCs and iECs have brain-specific properties and the co-culture of iPCs and iECs provides an in vitro BBB model that show inflammatory response. This study has significance in establishing micro-physiological systems for neurological disease modeling and drug screening.

Orthogonally Integrating Programmable Structural Color and Photo-Rewritable Fluorescence in Hydrazone Photoswitch-bonded Cholesteric Liquid Crystalline Network.

Design and fabrication of advanced security label showing superior performance in data encryption has attracted tremendous scientific interests. Especially, multifunctional optical labels capable of storing distinct information in different modes are highly demanded. Here, a fluorescent cholesteric liquid crystalline network (CLCN) film with programmable visible patterns and photo-rewritable fluorescent patterns was designed and prepared. The visible patterns were fixed by helical network and the colors of visible patterns were tunable by changing relative humidity (RH). The fluorescent patterns originated from dynamic isomerization of fluorescent hydrazones, exhibiting highly thermal stability and switching-ability controlled by light. The orthogonal construction of visible and fluorescent pattern enabled the novel CLCN to encrypt distinct information in reflective mode and in emissive mode, indicating its potential in anti-counterfeiting and information encryptions.

Robotic Taj Mahal Hepatectomy for Hilar Cholangiocarcinoma.

Hilar cholangiocarcinoma is the most common malignant tumor of the biliary tract. Radical surgical resection is the only effective treatment option. In this study, a 32-year-old male patient with Bismuth Type IVa hilar cholangiocarcinoma underwent radical robotic resection of hepatic S4b, S5, and S1 (Taj Mahal hepatectomy) combined with regional lymphadenectomy, hilar bile duct reconstruction, and hepaticojejunostomy by the robotic surgical system. Postoperative pathological examination showed moderately-differentiated adenocarcinoma of the hilar bile duct. The surgical margins of the liver and bile ducts were negative. Recovery was smooth and the patient was discharged on the 17th postoperative day. The robotic surgical system and associated multiple instruments along with flexible and precise movements is suitable for the local hepatectomy around the porta hepatis, and delicate reconstruction of the hilar bile duct with a smaller diameter. This first clinical application study found that robotic Taj Mahal hepatectomy for hilar cholangiocarcinoma is safe and feasible and needs more experience for the evaluation of its long-term outcomes.

Soft, Pressure-Tolerant, Flexible Electronic Sensors for Sensing under Harsh Environments.

Energy-efficient, miniaturized electronic ocean sensors for monitoring and recording various environmental parameters remain a challenge because conventional ocean sensors require high-pressure chambers and seals to survive the large hydrostatic pressure and harsh ocean environment, which usually entail a high-power supply and large size of the sensor system. Herein, we introduce soft, pressure-tolerant, flexible electronic sensors that can operate under large hydrostatic pressure and salinity environments, thereby eliminating the need for pressure chambers and reducing the power consumption and sensor size. Using resistive temperature and conductivity (salinity) sensors as an example for demonstration, the soft sensors are made of lithographically patterned metal thin films (100 nm) encapsulated with soft oil-infused elastomers and tested in a customized pressure vessel with well-controlled pressure and temperature conditions. The resistance of the temperature and pressure sensors increases linearly with a temperature range of 5-38 °C and salinity levels of 30-40 Practical Salinity Unit (PSU), respectively, relevant for this application. Pressure (up to 15 MPa) has shown a negligible effect on the performance of the temperature and salinity sensors, demonstrating their large pressure-tolerance capability. In addition, both temperature and salinity sensors have exhibited excellent cyclic loading behaviors with negligible hysteresis. Encapsulated with our developed soft oil-infused elastomer (PDMS, poly(dimethylsiloxane)), the sensor has shown excellent performance under a 35 PSU salinity water environment for more than 7 months. The soft, pressure-tolerant and noninvasive electronic sensors reported here are suitable for integration with many platforms including animal tags, profiling floats, diving equipment, and physiological monitoring.

Amplifying Molecular Scale Rotary Motion: The Marriage of Overcrowded Alkene Molecular Motor with Liquid Crystals.

Design and fabrication of macroscopic functional devices by molecular engineering is an emerging and effective strategy in exploration of advanced materials. Photoresponsive overcrowded alkene-based molecular motor (OAMM) is considered as one of the most promising molecular machines due to the unique rotary motion driven by light with high temporal and spatial precision. Amplifying the molecular rotary motions into macroscopic behaviors of photodirected systems links the molecular dynamics with macroscopic motions of materials, providing new opportunities to design novel materials and devices with a bottom-up strategy. In this review, recent developments of the light-responsive liquid crystal system triggered by OAMM will be summarized. The mechanism of amplification effect of liquid crystal matrix will be introduced first. Then progress of the OAMM-driven liquid crystal materials will be described including light-controlled photonic crystals, texture-tunable liquid crystal coating and microspheres, photoactuated soft robots, and dynamic optical devices. It is hoped that this review provides inspirations in design and exploration of light-driven soft matters and novel functional materials from molecular engineering to structural modification.

Reprogrammable Humidity-Driven Liquid Crystalline Polymer Actuator Enabled by Dynamic Ionic Bonds.

Liquid crystalline polymer (LCP) is a promising candidate in the design and fabrication of intelligent soft materials due to the combination of programmable anisotropy and elasticity. Here, a novel strategy to fabricate reprogrammable humidity-responsive LCP materials enabled by dynamic ionic cross-links were put forward. The prepared LCP film deforms reversibly with the change of relative humidity (RH). However, the humidity responsivity loses after soaking the film into CaCl2 solution because of the lock of hygroscopic groups by the formed ionic bonds. By selectively cross-linking specific regions of the LCP film, distinctive humidity-driven motions of the film could be realized. More interestingly, by the EDTA-2K solution treatment, ionic cross-links can be interrupted, leading the LCP film responsive to humidity again. Thanks to feasibly removable ionic cross-links, the humidity-directed soft actuator was totally reprogrammable. The behavior of the novel actuator could be manipulated by either the mesogens alignment or the spatially ionic treatment, providing a feasible but robust strategy to fabricate complex humidity-driven soft robots.

Freestanding Helical Nanostructured Chiro-Photonic Crystal Film and Anticounterfeiting Label Enabled by a Cholesterol-Grafted Light-Driven Molecular Motor.

Design and fabrication of freestanding chiro-photonic crystal film with the ability to change color over the whole visible light spectrum is appealing for anticounterfeiting technology and smart labels. Utilizing a newly synthesized light-responsive molecular motor functionalized with cholesterol (chol-MM) on the rotor, novel light-controlled photonic crystal is prepared by doping the novel chol-MM into liquid crystals (LCs). Thanks to the liquid crystalline cholesterol substituent, the chol-MM can be triggered by visible light (420 nm). At the same time, the miscibility of chol-MM in LC matrix is significantly enhanced. Integrating the chol-MM with thermochromic hydrogen-bonded LC matrix, thermal and light dual-responsive cholesteric LC (CLC) material is prepared, in which the nanoscale helical pitch is tunable by photo-induced molecular motions of chol-MM. More importantly, utilizing UV-initiated polymerization of the visible light-modulated CLC material, structural colored photonic crystal films with arbitrary colorful patterns are fabricated. Such freestanding helical nanostructured labels have potential in the application of encrypted communication and anticounterfeiting.