Effect of transcutaneous electrical nerve stimulation (TENS) on the electromyographic activity of human masticatory muscles in young people with normal occlusion.

STATEMENT OF PROBLEM: Transcutaneous electrical nerve stimulation (TENS) has been used in several clinical areas. However, the effect of TENS on the masticatory muscles of young individuals with normal occlusion remains unclear. PURPOSE: The purpose of the study was to assess the effect of TENS on the surface electromyographic (sEMG) activity of masticatory muscles in a young population with normal occlusion. MATERIAL AND METHODS: Twenty residents (5 men and 15 women, mean 24.27 ±2.59 years) of Dalian Stomatological Hospital were enrolled as the study participants. A trained operator collected the required information from the participants. The experiment was divided into 3 stages: pre-TENS acquisition, TENS application, and post-TENS acquisition. The pre-TENS stage was performed using surface electromyography (sEMG) (Myotronics Inc) to acquire the potential values of masticatory muscles in the following 3 states 5 times each: resting, intercuspal occlusion (ICO), and maximum voluntary clench (clenching). The potential values of the anterior of temporalis (TA), the masseter (MM), the sternocleidomastoid (SCM), and the anterior digastric (DA) muscles were collected in the resting state, and TA and MM were collected in the ICO and clenching states. During the TENS application phase, a TENS Unit device (J5 Myomonitor) (J5) was used on each participant for 45 minutes. The post-TENS acquisition phase involved the same procedure as the pre-TENS phase. The experimental data were recorded, and the normality of each group was analyzed using the Shapiro-Wilk test in a statistical software program (IBM SPSS Statistics, v26.0). The paired-sample t test was used to compare the differences in the mean values of sEMG and the asymmetry index (As); the independent-sample t test was used to compare the activity index (Ac) and torque index (To) (α=.05). RESULTS: Significant differences were observed in the mean potential values of TA, MM, LSCM, and RDA before and after TENS in the resting state and RTA, LMM, and RMM before and after TENS in the clenching state (P<.05). Moreover, although AsDA values showed a significant difference (P=.027) before and after TENS in the resting state, the differences in As values for the other muscles in the resting state were statistically similar. Furthermore, in each state, the mean values of Ac and To after TENS showed no significant differences before and after TENS (P>.05). CONCLUSIONS: The resting EMG values of the TA and MM differed significantly before and after TENS. After TENS, the resting EMG activity decreased, whereas the functional EMG activity tended to increase.

Quantum interactions in topological R166 kagome magnet.

Kagome magnet has been found to be a fertile ground for the search of exotic quantum states in condensed matter. Arising from the unusual geometry, the quantum interactions in the kagome lattice give rise to various quantum states, including the Chern-gapped Dirac fermion, Weyl fermion, flat band and van Hove singularity. Here we review recent advances in the study of the R166 kagome magnet (RT6E6, R = rare earths; T = transition metals; and E = Sn, Ge, etc) whose crystal structure highlights the transition-metal-based kagome lattice and rare-earth sublattice. Compared with other kagome magnets, the R166 family owns the particularly strong interplays between thedelectrons on the kagome site and the localizedfelectrons on the rare-earth site. In the form of spin-orbital coupling, exchange interaction and many-body effect, the quantum interactions play an essential role in the Berry curvature in both the reciprocal and real spaces of R166 family. We discuss the spectroscopic and transport visualization of the topological electrons hosted in the Mn kagome layer of RMn6Sn6and the various topological effects due to the quantum interactions, including the Chern-gap opening, the exchange-biased effect, the topological Hall effect and the emergent inductance. We hope this work serves as a guide for future explorations of quantum magnets.

Zn Microbatteries Explore Ways for Integrations in Intelligent Systems.

As intelligent microsystems develop, many revolutionary applications, such as the swallowing surgeon proposed by Richard Feynman, are about to evolve. Nonetheless, integrable energy storage satisfying the demand for autonomous operations has emerged as a major obstacle to the deployment of intelligent microsystems. A reason for the lagging development of integrable batteries is the challenge of miniaturization through microfabrication procedures. Lithium batteries, generated by the most successful battery chemistry, are not stable in the air, thus creating major manufacturing challenges. Other cations (Na+ , Mg2+ , Al3+ , K+ ) are still in the early stages of development. In contrast, the superior stability of zinc batteries in the air brings high compatibility to microfabrication protocols and has already demonstrated excellent practicability in full-sized devices. To obtain energy-dense and high-power zinc microbatteries within square-millimeter or smaller footprints, sandwich, pillar, and Swiss-roll configurations are developed. Thin interdigital and fiber microbatteries find their applications being integrated into wearable devices and electronic skin. It is foreseeable that zinc microbatteries will find their way into highly integrated microsystems unlocking their full potential for autonomous operation. This review summarizes the material development, configuration innovation, and application-oriented integration of zinc microbatteries.

Millipede genomes reveal unique adaptations during myriapod evolution.

The Myriapoda, composed of millipedes and centipedes, is a fascinating but poorly understood branch of life, including species with a highly unusual body plan and a range of unique adaptations to their environment. Here, we sequenced and assembled 2 chromosomal-level genomes of the millipedes Helicorthomorpha holstii (assembly size = 182 Mb; shortest scaffold/contig length needed to cover 50% of the genome [N50] = 18.11 Mb mainly on 8 pseudomolecules) and Trigoniulus corallinus (assembly size = 449 Mb, N50 = 26.78 Mb mainly on 17 pseudomolecules). Unique genomic features, patterns of gene regulation, and defence systems in millipedes, not observed in other arthropods, are revealed. Both repeat content and intron size are major contributors to the observed differences in millipede genome size. Tight Hox and the first loose ecdysozoan ParaHox homeobox clusters are identified, and a myriapod-specific genomic rearrangement including Hox3 is also observed. The Argonaute (AGO) proteins for loading small RNAs are duplicated in both millipedes, but unlike in insects, an AGO duplicate has become a pseudogene. Evidence of post-transcriptional modification in small RNAs-including species-specific microRNA arm switching-providing differential gene regulation is also obtained. Millipedes possesses a unique ozadene defensive gland unlike the venomous forcipules found in centipedes. We identify sets of genes associated with the ozadene that play roles in chemical defence as well as antimicrobial activity. Macro-synteny analyses revealed highly conserved genomic blocks between the 2 millipedes and deuterostomes. Collectively, our analyses of millipede genomes reveal that a series of unique adaptations have occurred in this major lineage of arthropod diversity. The 2 high-quality millipede genomes provided here shed new light on the conserved and lineage-specific features of millipedes and centipedes. These findings demonstrate the importance of the consideration of both centipede and millipede genomes-and in particular the reconstruction of the myriapod ancestral situation-for future research to improve understanding of arthropod evolution, and animal evolutionary genomics more widely.

Molecular characterization and expression analysis of a QM protein gene in Chinese mitten crab Eriocheir sinensis.

QM protein was previously discovered as a tumor suppressor, and numerous studies have shown that QM protein also played important roles in the immune responses. To investigate the potential roles of the QM protein gene in Eriocheir sinensis, the QM protein gene (designated as EsQM) has been cloned from E. sinensis using the rapid amplification of cDNA ends (RACE) technique. The cDNA of EsQM is 781 bp in length, consisting of a 654 bp open reading frame (ORF), encoding 219 amino acids, a 27 bp 5' untranslated region (UTR) and a 94 bp 3' UTR. The EsQM protein has a calculated molecular weight of 25.4 kDa and a theoretical isoelectric point of 10.10. The deduced protein sequence of EsQM contains a Ribosomal_L16 domain, an SH3-binding motif, an N-acylation site, two putative antibiotic binding sites, two putative protein kinase C phosphorylation sites, and two amidation sites. EsQM is extremely conserved and exhibits more than 85% similarities to previously identified arthropod QM protein genes. By real-time quantitative PCR (qPCR) analysis, we found that EsQM mRNA transcripts were detectable in all the examined tissues, with the highest expression in hemocytes. The mRNA expression of EsQM in hemocytes was significantly upregulated after the stimulation of Aeromonas hydrophila or polybrominated diphenyl ether-47 (BDE-47). Moreover, EsQM mRNA expression in hemocytes responded more quickly and lasted longer when stimulated by A.hydrophila than BDE-47. Thus, EsQM can respond to bacterial infection and environmental pollution, and might be involved in the defense mechanism to both biological and non-biological stimulation of arthropods.

Frailty knowledge level and its influencing factors among older adults in China.

Raising older adults' frailty knowledge level and encouraging them to actively engage in the prevention and treatment of frailty is essential to promote healthy aging. This cross-sectional study investigated frailty knowledge level and its influencing factors in community-dwelling older adults in China. A total of 734 older adults were included in the analysis. About half of them misjudged their frailty state (42.50%), and 17.17% obtained frailty knowledge in the community. Those who were female, lived in rural areas, lived alone, had not attended school, had a monthly income <3,000RMB, were at risk for malnutrition, were depressed, and were socially isolated were more likely to have lower frailty knowledge level. Those with advanced age and pre-frailty or frailty stage were more knowledgeable about frailty. The group with the highest proportion of low frailty knowledge level was those who had never attended school or completed primary school and had loose friend ties (98.7%). It is crucial to develop tailored intervention to raise frailty knowledge level in older adults in China.

TMD Design by an Entropy Index for Seismic Control of Tall Shear-Bending Buildings.

This study proposes a new arrangement-tuning method to maximize the potential of tuned mass dampers (TMDs) in decreasing the seismic responses of tall buildings. The method relies on a Grammian-based entropy index with the physical meaning of covariance responses to white noise without the involvement of external inputs. A twelve-story RC frame-shear wall building was used as an example to illustrate the method. Indices were computed for the building with TMDs placed on different stories and tuning to different modes and were compared with responses to white noise (colored) time histories. Results showed that greater index reduction cases agree well with greater story-drift reductions cases, despite the differences in the time step of the white noises and structural model types (pure shear vs. shear-bending), and the optimal TMD is not necessarily the traditional "roof-1st mode tuning" case. Comparisons were also made for the shear-bending building under seven earthquake excitations. It is found that, though TMDs are not full-band effective controllers, the index-selected TMDs still perform the best in three out of seven earthquakes. So, the proposed internal-property-based entropy index provides a good controller design for large-scale structures under unpredictable none-stationary excitations.

The willingness and influencing factors to choose smart senior care among old adults in China.

BACKGROUND: Population aging has become an escalating issue in China resulting in increasing healthcare demand. Smart senior care has the potential to help older adults live independently and relieve the pressure of healthcare including home-based care. This study aimed to explore Chinese older adults' preferred access models and service content of smart senior care and factors affecting their willingness to choose smart senior care. METHODS: This was a cross-sectional study. A total of 760 community-dwelling older adults from Xuzhou, China were included in this study. Their demographics, family support, health status, smart senior care use, and willingness to choose smart senior care were collected. The Chi-square test was used for single factor analysis of each variable. The statistically significant variables were included in the logistics regression model to analyze factors influencing older adults' willingness to choose smart senior care. The chi-square goodness of fit test was used to analyze the preferred content and access models of smart senior care; the Bonferroni method was used to correct the results. RESULTS: The finding indicated that participants' age, number of children, frequency of children visiting parents, adequate senior care, self-reported health, chronic diseases, smartphone use, and attitude toward smart senior care were significantly associated with their willingness to choose the smart senior care (p < 0.05). For smart senior care access models, participants preferred the remote monitoring model, telephone call model, and the community site model over the health smart home model and the smart application platform model. There was no statistical difference among these three preferred access models (p' > 0.005). Regarding service content, participants desired medical care service the most (p' < 0.005). CONCLUSIONS: Chinese older adults' willingness to choose smart senior care is affected by personal, family, health, and other factors. To develop China's senior care, we should consider their demand and preference for smart senior care. It is important to enrich the content of smart senior care, especially on medical care services, and maintain the dynamic balance between supply and demand using a diverse supply approach.

Preclinical safety assessment of toxicity and biodistribution of oncolytic virus HSV-1 expressing human PD-1 antibody in mice.

HSV-1/hPD-1 is composed of engineered herpes simplex virus type-1 and two inserted copies of the human PD-1 antibody sequence. It is a novel oncolytic virus product designed to cure malignancies. The objective of this study was to estimate its toxicity in mice. In the single-dose toxicity study, no mortality and abnormal symptoms were observed in animals injected with 4.0 × 107 pfu/mouse dose. In the repeat-dose toxicity study, HSV-1/hPD-1 in animals intramuscularly treated with 1.0 × 107, 2.0 × 107, or 4.0 × 107 pfu/mouse doses was well tolerated in terms of clinical observation, body weight, food consumption, hematology and biochemistry indexes, T lymphocyte counting, immune reaction, and organ weight, except for some histopathological changes, such as the irreversible degeneration of the sciatic nerve, which was considered related to the adopted administration route. Synchronously, a biodistribution study in mice was performed to examine whether HSV-1/hPD-1 could spread to the injection site, gonads, liver, lung, heart, mesenteric and inguinal lymph nodes, skin, dorsal root ganglia, and blood, and then be gradually eliminated. Thus, two safety dose levels-the maximum tolerance dose of 4.0 × 107 pfu/mouse and the no-observed-adverse-effect-level dose of 1.0 × 107 pfu/mouse-were determined to help design patients' dose regimens. Our research data have been successfully accepted for investigational new drug (IND) application in China.

The association between Roussouly sagittal alignment type and risk for adjacent segment degeneration following short-segment lumbar interbody fusion: a retrospective cohort study.

BACKGROUND: To date, the influence of Roussouly type on development of adjacent segment degeneration (ASD) after lumber fusion is still not fully explored, and the current study is aimed to evaluate the effect of Roussouly type on development of radiological ASD after single-level lumber fusion, and to compare the Roussouly types and spinopelvic parameters among those with different degenerative patterns of ASDs on sagittal plane. METHODS: A retrospective review of 288 patients underwent L4/5 or L5/S1 single-level posterior interbody fusions between January 2016 and December 2018 with a minimum 2-year follow up was performed. Radiological ASDs were identified and divided into 3 groups according to different degenerative patterns of the cephalad adjacent level on sagittal plane, including the types of retrolisthesis (Group A), anterolisthesis (Group B), and axial disc space narrowing (Group C). Roussouly types and radiological measurements were compared among three groups and potential risk factors for ASD were evaluated. RESULTS: Radiological ASD was found in 59 (20.5%) cases, in which patients with Roussouly type-2 was the most common. While, on subgroup analysis among three ASD groups, Roussouly type-1 occupied the highest proportion in Group A, differ in Group B and Group C, both with Type-2 as the most common. Moreover, Group A had significantly lower pelvic tilt (PT), larger sacral slope (SS), and larger segmental angle (SA) than Group B and Group C, which showed a more anteverted pelvic in Group A. Multivariate regression analysis noted Roussouly type, preoperative PT, and ∆PI-LL as the independent risk factors for radiological ASD. CONCLUSION: Roussouly type was significantly associated with the development of radiological ASD; however, the Roussouly types and spinal pelvic parameters were varied among different sagittal degenerative patterns of ASD, which was important in restoring optimal lumbar sagittal alignments in initial surgery.

Rethinking Sesquiterpenoids: A Widespread Hormone in Animals.

The sesquiterpenoid hormone juvenile hormone (JH) controls development, reproduction, and metamorphosis in insects, and has long been thought to be confined to the Insecta. While it remains true that juvenile hormone is specifically synthesized in insects, other types or forms of sesquiterpenoids have also been discovered in distantly related animals, such as the jellyfish. Here, we combine the latest literature and annotate the sesquiterpenoid biosynthetic pathway genes in different animal genomes. We hypothesize that the sesquiterpenoid hormonal system is an ancestral system established in an animal ancestor and remains widespread in many animals. Different animal lineages have adapted different enzymatic routes from a common pathway, with cnidarians producing farnesoic acid (FA); non-insect protostomes and non-vertebrate deuterostomes such as cephalochordate and echinoderm synthesizing FA and methyl farnesoate (MF); and insects producing FA, MF, and JH. Our hypothesis revolutionizes the current view on the sesquiterpenoids in the metazoans, and forms a foundation for a re-investigation of the roles of this important and yet neglected type of hormone in different animals.

Single-Cell Atlas of the Drosophila Leg Disc Identifies a Long Non-Coding RNA in Late Development.

The Drosophila imaginal disc has been an excellent model for the study of developmental gene regulation. In particular, long non-coding RNAs (lncRNAs) have gained widespread attention in recent years due to their important role in gene regulation. Their specific spatiotemporal expressions further support their role in developmental processes and diseases. In this study, we explored the role of a novel lncRNA in Drosophila leg development by dissecting and dissociating w1118 third-instar larval third leg (L3) discs into single cells and single nuclei, and performing single-cell RNA-sequencing (scRNA-seq) and single-cell assays for transposase-accessible chromatin (scATAC-seq). Single-cell transcriptomics analysis of the L3 discs across three developmental timepoints revealed different cell types and identified lncRNA:CR33938 as a distal specific gene with high expression in late development. This was further validated by fluorescence in-situ hybridization (FISH). The scATAC-seq results reproduced the single-cell transcriptomics landscape and elucidated the distal cell functions at different timepoints. Furthermore, overexpression of lncRNA:CR33938 in the S2 cell line increased the expression of leg development genes, further elucidating its potential role in development.

Rare Earth Engineering in RMn_{6}Sn_{6} (R=Gd-Tm, Lu) Topological Kagome Magnets.

Exploration of the topological quantum materials with electron correlation is at the frontier of physics, as the strong interaction may give rise to new topological phases and transitions. Here we report that a family of kagome magnets RMn_{6}Sn_{6} manifest the quantum transport properties analogical to those in the quantum-limit Chern magnet TbMn_{6}Sn_{6}. The topological transport in the family, including quantum oscillations with nontrivial Berry phase and large anomalous Hall effect arising from Berry curvature field, points to the existence of Chern gapped Dirac fermions. Our observation demonstrates a close relationship between rare-earth magnetism and topological electron structure, indicating the rare-earth elements can effectively engineer the Chern quantum phase in kagome magnets.

Genome of the four-finger threadfin Eleutheronema tetradactylum (Perciforms: Polynemidae).

BACKGROUND: Teleost fish play important roles in aquatic ecosystems and aquaculture. Threadfins (Perciformes: Polynemidae) show a range of interesting biology, and are of considerable importance for both wild fisheries and aquaculture. Additionally, the four-finger threadfin Eleutheronema tetradactylum is of conservation relevance since its populations are considered to be in rapid decline and it is classified as endangered. However, no genomic resources are currently available for the threadfin family Polynemidae. RESULTS: We sequenced and assembled the first threadfin fish genome, the four-finger threadfin E. tetradactylum. We provide a genome assembly for E. tetradactylum with high contiguity (scaffold N50 = 56.3 kb) and high BUSCO completeness at 96.5%. The assembled genome size of E. tetradactylum is just 610.5 Mb, making it the second smallest perciform genome assembled to date. Just 9.07-10.91% of the genome sequence was found to consist of repetitive elements (standard RepeatMasker analysis vs custom analysis), making this the lowest repeat content identified to date for any perciform fish. A total of 37,683 protein-coding genes were annotated, and we include analyses of developmental transcription factors, including the Hox, ParaHox, and Sox families. MicroRNA genes were also annotated and compared with other chordate lineages, elucidating the gains and losses of chordate microRNAs. CONCLUSIONS: The four-finger threadfin E. tetradactylum genome presented here represents the first available genome sequence for the ecologically, biologically, and commercially important clade of threadfin fish. Our findings provide a useful genomic resource for future research into the interesting biology and evolution of this valuable group of food fish.

Parasitic Ferromagnetism in Few-Layered Transition-Metal Chalcogenophosphate.

Since the rise of two-dimensional (2D) semiconductors, it seems that electronic devices will soon be upgraded with spintronics, in which the manipulation of spin degree of freedom endows it obvious advantages over conventional charge-based electronics. However, as the most crucial prerequisite for the above-mentioned expectation, 2D semiconductors with adjustable magnetic interaction are still rare, which has greatly hampered the promotion of spintronics. Recently, transition metal phosphates have attracted tremendous interest due to their intrinsic antiferromagnetism and potential applications in spintronics. In the work described herein, parasitic ferromagnetism is achieved for the first time by exfoliating an antiferromagnetic chalcogenophosphate to a few layers. Taking the transition metal chalcogenophosphate Mn2P2S6 as an example, the antiferromagnetic transition at the Néel temperature is completely suppressed, and the magnetic behaviors of the as-obtained few-layered Mn2P2S6 are dominated by parasitic ferromagnetism. We experimentally verify an electron redistribution by which part of the Mn 3d electrons migrate and redistribute on P atoms in few-layered Mn2P2S6 due to the introduced Mn vacancies. The results demonstrated here broaden the tunability of the material's magnetic properties and open up a new strategy to rationally design the magnetic behaviors of 2D semiconductors, which could accelerate the applications of spintronics.

Proteomic Analysis of the Venom of Jellyfishes Rhopilema esculentum and Sanderia malayensis.

Venomics, the study of biological venoms, could potentially provide a new source of therapeutic compounds, yet information on the venoms from marine organisms, including cnidarians (sea anemones, corals, and jellyfish), is limited. This study identified the putative toxins of two species of jellyfish-edible jellyfish Rhopilema esculentum Kishinouye, 1891, also known as flame jellyfish, and Amuska jellyfish Sanderia malayensis Goette, 1886. Utilizing nano-flow liquid chromatography tandem mass spectrometry (nLC-MS/MS), 3000 proteins were identified from the nematocysts in each of the above two jellyfish species. Forty and fifty-one putative toxins were identified in R. esculentum and S. malayensis, respectively, which were further classified into eight toxin families according to their predicted functions. Amongst the identified putative toxins, hemostasis-impairing toxins and proteases were found to be the most dominant members (>60%). The present study demonstrates the first proteomes of nematocysts from two jellyfish species with economic and environmental importance, and expands the foundation and understanding of cnidarian toxins.

Intra-Articular Injection of Tranexamic Acid on Perioperative Blood Loss During Unicompartmental Knee Arthroplasty.

BACKGROUND Tranexamic acid (TXA) is safe and effective in total knee arthroplasty (TKA) for the prevention of bleeding. However, the role of TXA during unicompartmental knee arthroplasty (UKA) remains unclear. This study aimed to compare operative blood loss in patients undergoing UKA treated with an intra-articular injection of TXA with controls undergoing UKA without TXA. MATERIAL AND METHODS The prospective study included 101 patients who underwent UKA between January 2014 to March 2018. All patients completed a preoperative routine examination and were randomized to the study group (n=54) and the control group (n-47). The study group was given an articular injection of TXA (1.5 g in 50 ml normal saline) after the fascia was closed; the control group was injected with the same volume of normal saline. Blood volumes were measured from the drainage tube of the two groups during 48 hours. Total blood loss, postoperative drainage, hidden blood loss, blood transfusion rates, postoperative hemoglobin values, indicators of coagulation function, and the rates of wound complications were recorded. RESULTS Total blood loss in the study group was 745.6±105.1 ml, total drainage volume was 353.9±79.5 ml, and the hidden blood loss was 391.7±80.5 ml, which were all significantly lower when compared with the control group (P<0.05). None of the patients in the two groups suffered complications of surgery. CONCLUSIONS Intra-articular injection of TXA significantly reduced the total blood loss in patients who underwent UKA and did not increase the rate of complications.

Three-Layered Hollow Nanospheres Based Coatings with Ultrahigh-Performance of Energy-Saving, Antireflection, and Self-Cleaning for Smart Windows.

In this study, a well-controlled interfacial engineering method for the synthesis of SiO2 /TiO2 /VO2 three-layered hollow nanospheres (TLHNs) and TLHNs-based multifunctional coatings is reported. The as-prepared coatings allow for an outstanding integration of thermochromism from the outer VO2 (M) layer, photocatalytic self-cleaning capability from the middle TiO2 (A) layer, and antireflective property from internal SiO2 HNs. The TLHNs coatings exhibit excellent optical performance with ultrahigh luminous transmittance (Tlum-l = 74%) and an improved solar modulation ability (ΔTsol = 12%). To the best knowledge, this integrated optical performance is the highest ever reported for TiO2 /VO2 -based thermochromic coatings. An ingenious computation model is proposed, which allows the neff of nanostructured coatings to be rapidly obtained. The experimental and calculated results reveal that the unique three-layered structure significantly reduces the refractive index (from 2.25 to 1.33 at 600 nm) and reflectance (Rave, from 22.3 to 5.3%) in the visible region as compared with dense coatings. Infrared thermal imaging characterization and self-cleaning tests provide valid evidence of SiO2 /TiO2 /VO2 TLHNs coatings' potential for energy-saving and self-cleaning smart windows. The exciting inexpensive and universal fabrication process for well-defined structures may inspire various developments in processable and multifunctional devices.

Reversible Semicrystalline Polymer as Actuators Driven by Organic Solvent Vapor.

A semicrystalline polymer actuator, which is responsive to solvent vapor with fast and large scale locomotion, is described. The thermoset semicrystalline polymer can be easily synthesized from crystallizable polyester segment poly (ε-caprolactone) and isophorone diisocyanate trimer. Organic solvent vapor is used to induce the reversible swelling-crystallization conversion of the crystallizable polyester segment, resulting in its expansion/shrinkage. The contraction of the polymer actuator (1 mm thick) needs only ≈4 s in room temperature. When exposed to air the polymer actuator can exhibit a fast self-oscillation. Then, a soft crawler based on this polymer is demonstrated. Driven by organic solvent it walks rapidly and steadily. The microscope images show the fast swelling-crystallization conversion that gives rise to reversible shape changes of the polymer.

Perceptual Learning Induces Persistent Attentional Capture by Nonsalient Shapes.

Visual attention can be attracted automatically by salient simple features, but whether and how nonsalient complex stimuli such as shapes may capture attention in humans remains unclear. Here, we present strong electrophysiological evidence that a nonsalient shape presented among similar shapes can provoke a robust and persistent capture of attention as a consequence of extensive training in visual search (VS) for that shape. Strikingly, this attentional capture that followed perceptual learning (PL) was evident even when the trained shape was task-irrelevant, was presented outside the focus of top-down spatial attention, and was undetected by the observer. Moreover, this attentional capture persisted for at least 3-5 months after training had been terminated. This involuntary capture of attention was indexed by electrophysiological recordings of the N2pc component of the event-related brain potential, which was localized to ventral extrastriate visual cortex, and was highly predictive of stimulus-specific improvement in VS ability following PL. These findings provide the first evidence that nonsalient shapes can capture visual attention automatically following PL and challenge the prominent view that detection of feature conjunctions requires top-down focal attention.