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In this article, we proposed a novel piezoelectric energy harvester based on hierarchical auxetic structures to improve the power output. The auxetic structure can harvest more energy compared with a traditional flat energy harvester since the piezoelectric element in two directions can be stretched simultaneously due to the effects of the negative Poisson's ratio. Furthermore, the hierarchical auxetic structure can produce a smaller negative Poisson's ratio and deform more sufficiently to improve the energy harvesting efficiency. Therefore, the proposed hierarchical auxetic energy harvester (HAEH) can produce higher power than the normal reentrant auxetic one. A numerical model is established by employing COMSOL Multiphysics software to investigate the performance of the HAEH and verified by comparing it with the experimental results of the physical prototype fabricated by machining. In addition, an optimization framework based on a machine learning model and multiobjective nondominated sorting genetic algorithm optimization is developed to optimize the HAEH for better energy harvesting performance. The HAEH has a bright future for battery-free sensors in various engineering fields.

Biomechanical energy harvesters can capture biomechanical energy from human motion and generate electricity for powering wearable and portable electronics. Thanks to that, the widely used body-worn devices can be battery-free and eliminate battery capacity limitations. This article develops a lightweight piezoelectric bending beam-based human knee energy harvester to generate electricity during walking. To enhance the performance, especially in the stance phase, we propose a new design and introduce free vibration in the stance phase to improve the output voltage and power. Specifically, one end of the bending beam is released and moves freely, such that the bending beam experiences free vibration in the stance phase. While in the swing phase, the bending beam still undertakes forced motion. Besides, a proof mass is mounted on the bending beam to tune the free vibration. Experimental results indicate that compared with the previous design, the free vibration can improve the average output power by 52.3%. When walking at 7 km/h on a treadmill, the average power output can reach 43.4 mW. This work significantly facilitates the further development of biomechanical energy harvesters. The output power is improved by 10 to 100 times compared with the existing works.

This report develops a point-of-use chemical trigger and applies it to a dual-functional chemical encryption chip that enables manual and digital identification with enhanced coding security levels suitable for on-site information verification. The concept relies on conducting continuous chemical synthesis and chromatographic separation of specified compounds on a paper device in a straightforward sketch. In addition to single-step chemical reactions, cascade syntheses and operations involving components of distinct mobilities are also demonstrated. The condensation of dione and hydrazine is first demonstrated on a linear paper reactor, where precursors can mix to react, followed by final product separation under optimized conditions. This linear paper reactor design can also support a multistep cascade Wittig reaction by controlling the relative mobility of reactants, intermediates, and final products. Furthermore, a three-dimensional paper reactor with appropriate mobile phases helps to initiate complex solvent system-driven azide–alkyne cycloaddition. By the use of a three-dimensional device design for spatially limited interdevice reactant transportation, reactants crossing designated boundaries trigger confined chemical reactions at specific positions. Accumulation of repetitive reactions leads to successful product gradient generation and mixing effects, representing a fully controllable intersubstrate chemical operation on the platform. Standing on initiating desired chemical reactions at particular interface regions, integration of appropriate selective reaction area, numerical digits overlay, color diversity, and mobile recognition realizes this dual-functional multicoding encryption process.

A 73-year-old woman having a throat lump sensation and dysphagia for the past several months presented at our otorhinolaryngology outpatient clinic. A physical examination disclosed a protruding subepithelial mass over the right tonsil fossa. The mass was not tender and had no mucosal lesions or signs of active infection. Therefore, we arranged face and neck computed tomography scans, which reported a solitary osseous lesion over the anterior-right aspect of the C1-2 joint. Considering the rarity and unfamiliar anatomy of this disease, we built a 3D-printed model to assist with the surgical rehearsal of the procedure as well as with a preoperation discussion with the patient and her family. We arranged a combined Otolaryngology-Neurosurgery department approach after discussion with the neurosurgeon and successfully removed the lesion without sacrificing the overlying longus capitis muscle. The pathology examination revealed no evidence of malignancy. The final diagnosis was cervical spine solitary osteochondroma. The patient had a complete recovery of both oral cavity and normal swallowing function. No tumor recurred during the 3-year follow-up. On the basis of this case, in-house 3D-printing technology can offer a rapid, reliable model for an interdisciplinary team to use to enhance personalized presurgical planning, thus providing better patient engagement during hospitalization.

Controlling the morphology of Pt nanostructures can provide a great opportunity to improve their catalytic properties by increasing their active sites and atomic utilization. Here, Pt nanodentrites (NDs) dispersed on intrinsic vacancy-rich hollow nitrogen-doped carbon (Pt@HNC-V) have been successfully prepared through an integrated strategy of in situCl–mediated growth and carbon intrinsic vacancy engineering. Raman and electron paramagnetic resonance measurements have demonstrated that our method enables selective transformation of precursors into vacancy-rich samples or vacancy-free ones through a variable etching route. Moreover, X-ray absorption and X-ray photoelectron spectroscopy further verified that the vacancy-rich sample (Pt@HNC-V-800) demonstrates a lower Pt–Pt bond coordination number (8.64) and a stronger electron-donating effect of Pt compared with the vacancy-free Pt@HNC sample. In addition, density functional theory calculations indicate that the vacancy-rich Pt@HNC-V lowers the oxygen overpotential, resulting in optimized adsorption energies of oxygen reduction reaction (ORR) intermediates on Pt NDs and thus yielding improved oxygen reduction reaction activity. Benefiting from Pt NDs with abundant active sites and the strong electronic effect between them and the intrinsic carbon vacancy substrate, the half-wave potential of ORR for Pt@HNC-V-800 is as high as 0.947 V, and the mass activity is 1.55 A mg–1Pt, which is significantly higher than that of commercial Pt/C. The synergy between Pt NDs and carbon intrinsic vacancy engineering can enhance the overall ORR performance, which is beneficial for material preparations in the field of energy and catalysis.

The largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki1, persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct2–4. Its demise is enigmatic considering that it was one of the few Asian great apes to go extinct in the last 2.6 million years, whereas others, including orangutan, survived until the present5. The cause of the disappearance of G. blackiremains unresolved but could shed light on primate resilience and the fate of megafauna in this region6. Here we applied three multidisciplinary analyses—timing, past environments and behaviour—to 22 caves in southern China. We used 157 radiometric ages from six dating techniques to establish a timeline for the demise of G. blacki. We show that from 2.3 million years ago the environment was a mosaic of forests and grasses, providing ideal conditions for thriving G. blackipopulations. However, just before and during the extinction window between 295,000 and 215,000  years ago there was enhanced environmental variability from increased seasonality, which caused changes in plant communities and an increase in open forest environments. Although its close relative Pongo weidenreichimanaged to adapt its dietary preferences and behaviour to this variability, G. blackishowed signs of chronic stress and dwindling populations. Ultimately its struggle to adapt led to the extinction of the greatest primate to ever inhabit the Earth.

Recent theoretical and experimental studies of the interlayer Dzyaloshinskii–Moriya interaction (DMI) have sparked great interest in its implementation into practical magnetic random-access memory (MRAM) devices, due to its capability to mediate long-range chiral spin textures. So far, experimental reports focused on the observation of interlayer DMI, leaving the development of strategies to control interlayer DMI’s magnitude unaddressed. Here, we introduce an azimuthal symmetry engineering protocol capable of additive/subtractive tuning of interlayer DMI through the control of wedge deposition of separate layers and demonstrate its capability to mediate field-free spin–orbit torque (SOT) magnetization switching in both orthogonally magnetized and synthetic antiferromagnetically coupled systems. Furthermore, we showcase that the spatial inhomogeneity brought about by wedge deposition can be suppressed by specific azimuthal engineering design, ideal for practical implementation. Our findings provide guidelines for effective manipulations of interlayer DMI strength, beneficial for the future design of SOT-MRAM or other spintronic devices utilizing interlayer DMI.

BackgroundThe ZFHX3gene plays vital roles in embryonic development, cell proliferation, neuronal differentiation and neuronal death. This study aims to explore the relationship between ZFHX3variants and epilepsy.MethodsWhole-exome sequencing was performed in a cohort of 378 patients with partial (focal) epilepsy. A Drosophila Zfh2knockdown model was used to validate the association between ZFHX3and epilepsy.ResultsCompound heterozygous ZFHX3variants were identified in eight unrelated cases. The burden of ZFHX3variants was significantly higher in the case cohort, shown by multiple/specific statistical analyses. In Zfh2knockdown flies, the incidence and duration of seizure-like behaviour were significantly greater than those in the controls. The Zfh2knockdown flies exhibited more firing in excitatory neurons. All patients presented partial seizures. The five patients with variants in the C-terminus/N-terminus presented mild partial epilepsy. The other three patients included one who experienced frequent non-convulsive status epilepticus and two who had early spasms. These three patients had also neurodevelopmental abnormalities and were diagnosed as developmental epileptic encephalopathy (DEE), but achieved seizure-free after antiepileptic-drug treatment without adrenocorticotropic-hormone/steroids. The analyses of temporal expression (genetic dependent stages) indicated that ZFHX3orthologous were highly expressed in the embryonic stage and decreased dramatically after birth.ConclusionZFHX3is a novel causative gene of childhood partial epilepsy and DEE. The patients of infantile spasms achieved seizure-free after treatment without adrenocorticotropic-hormone/steroids implies a significance of genetic diagnosis in precise treatment. The genetic dependent stage provided an insight into the underlying mechanism of the evolutional course of illness.

This study focuses on reachability problems in differential games. An improved level set (LS) method for computing reachable tubes (RTs) is proposed in this article. The RT is described as a sub-LS of a value function, which is the viscosity solution of a Hamilton–Jacobi (HJ) equation with running cost. We generalize the concept of RTs and propose a new class of RTs, which are referred to as cost-limited one. In particular, a performance index can be specified for the system, and A set of initial states of the system’s evolutions that can reach the target set before the performance index grows to a given allowable cost is referred to as a cost-limited RT (CRT). Such an RT can be obtained by specifying the corresponding running cost function for the HJ equation. Different nonzero sub-LSs of the viscosity solution of the HJ equation at a certain time point can be used to characterize the CRTs with different allowable costs (or the RTs with different time horizons), thus reducing the storage space consumption. The validity and accuracy of the suggested technique are demonstrated via some examples.

Aim: This study aimed to estimate the chronic disease-free life expectancy (CDFLE) for distinct joint phenotypes of physical activity and obesity defined by six indicators in resource-limited areas. Subject and methods: In this study, a total of 38,789 participants aged 18 to 79 were recruited from the Henan rural cohort study. Logistic regression analysis was applied to assess the independent and combined effects of obesity and physical activity on chronic disease. The CDFLE according to obesity indicators and physical activity was measured via the Sullivan method. Results: Compared to participants who were physically active and nonobese defined by BMI, the multivariable-adjusted OR (95% CI) of the risk for prevalent chronic disease was 2.024 (1.833, 2.236) among those with obesity and physical inactivity, and the corresponding estimate for obese but physically active participants was 1.684 (1.550, 1.829). Compared with nonobese and physically active individuals, those with physical inactivity plus obesity classified by BMI, waist circumference, waist-to-hip ratio, waist-to-height ratio, body fat percent, and visceral fat index lost 4.42 (2.73, 6.12), 4.10 (2.95, 5.25), 4.84 (3.69, 5.98), 4.59 (3.47, 5.70), 3.86 (2.59, 5.13), and 3.81 (2.63, 4.99) years of CDFLE at age 50, respectively. The corresponding estimates for those who were obese but physically active were 2.75 (0.78, 4.72), 2.64, (1.43, 3.85), 3.14 (1.99, 4.30), 3.23 (2.09, 4.38), 2.22 (0.96, 3.48), and 1.85 (0.66, 3.03) years. Conclusion: Healthy body weight and physical activity were beneficial for chronic disease and CDFLE, and physical activity attenuated the negative effects of obesity.

A novel mini-light-emitting diode (mini-LED) driving circuit based on the low-temperature polysilicon thin-film transistors (LTPS TFTs) for used in the active matrix (AM) backlight unit (BLU) of a liquid-crystal display (LCD) is proposed. By the pulsewidth modulation driving method, the mini-LED is operated at a high luminance efficacy point than that is achieved using the pulse-amplitude modulation (PAM) method to reduce the power consumption at a low gray level. To generate the uniform driving current of the mini-LED, the threshold voltage ( ${V}_{\text {TH}}$ ) variation of the driving thin-film transistor (TFT) is compensated for by the diode-connection structure. Since the large driving current could exacerbate the current–resistance effect in the power source line, the negative supply voltage (VSS) ${I}$ – ${R}$ rise is also compensated for. The ${V}_{\text {TH}}$ variation of the control TFT is compensated for by the matched TFT method to ensure the precise emission time of the mini-LED. The results of a simulation based on the fitting model of the LTPS TFTs indicate that the relative time shifts are below $0.581~\mu \text{s}$ . The samples of the proposed circuit are fabricated to verify the feasibility of compensation in the proposed mini-LED BLU. Measurements demonstrate that the maximum error rate among samples is 1.46%. When the VSS rises from −6 to −5 V, the measured current error rates are all less than 6.03%. Hence, the proposed circuit is verified to generate uniform driving currents for the mini-LED BLU of LCDs.

Various active back-support exoskeletons have been developed to assist manual materials handling work for low back injury prevention. Existing back-support exoskeleton actuation either suffers from rigid transmission structure, or fails to efficiently generate assistance via portable actuation system with flexible transmissions. In this article, a novel cable-driven series elastic actuation (CSEA) system is proposed to realize a flexible and portable back-support exoskeleton design with safe, efficient, and sufficient assistive torque output capability. The CSEA system realizes a flexible actuation based on cable transmission for an ergonomic human–exoskeleton interaction. Based on a torsion spring–support beam mechanism, it achieves an efficient assistance output capability to prevent high cable force demand and resultant lumbar compression, assuring a safe and synergistic operation for flexible exoskeleton actuation. Meanwhile, this mechanism enables the CSEA system to integrate series elastic actuator (SEA) with cable transmission and operates with multiple statuses to leverage SEA advantages and to overcome its torque output limitation. Dynamic model is established for the CSEA system, and a unified torque controller is designed for stable, continuous, and accurate torque control of the CSEA system despite its discontinuous dynamics during operation status transition. The efficacy of the closed-loop CSEA system to enable an ergonomic and efficient back-support exoskeleton actuation with the capability of accurately delivering desired level of assistance is verified via bench tests and human tests. Results verified that the CSEA system actuated exoskeleton can effectively reduce activity of relevant muscles during trunk flexion and extension motions compared to no exoskeleton case, validating successful application of the CSEA system on the exoskeleton for an effective back support effect.

ABSTRACTThis study examines how novice teachers engage with the emotion of anger in their professional work. We generated 155 Chinese teachers’ written reflections on how they felt, expressed, and regulated anger. The study revealed three findings: 1) the primary sources of the teachers’ anger were related to students; 2) the majority of teachers tended to express anger destructively; 3) some teachers lacked emotional competence to regulate anger. The intensifying emotional labour in the teaching profession, the professional prematurity of novice teachers, and the stringent emotional rules in Chinese schools jointly contributed to the identified patterns. This study generates new insights into novice teachers’ anger-related experiences, highlights the socio-cultural dimension of teacher anger, and suggests practical implications for supporting teachers in making sense of and acting on anger more consciously and effectively.

Individuals with depression have the highest lifetime prevalence of suicide attempts (SA) among mental illnesses. Numerous neuroimaging studies have developed biomarkers from task-related neural activation in depressive patients with SA, but the findings are inconsistent. Empowered by the contemporary interconnected view of depression as a neural system disorder, we sought to identify a specific brain circuit utilizing published heterogeneous neural activations. We systematically reviewed all published cognitive and emotional task-related functional MRI studies that investigated differences in the location of neural activations between depressive patients with and without SA. We subsequently mapped an underlying brain circuit functionally connecting to each experimental activation using a large normative connectome database (n= 1000). The identified SA-related functional network was compared to the network derived from the disease control group. Finally, we decoded this convergent functional connectivity network using microscale transcriptomic and chemo-architectures, and macroscale psychological processes. We enrolled 11 experimental tasks from eight studies, including depressive patients with SA (n= 147) and without SA (n= 196). The heterogeneous SA-related neural activations localized to the somato-cognitive action network (SCAN), exhibiting robustness to little perturbations and specificity for depression. Furthermore, the SA-related functional network was colocalized with brain-wide gene expression involved in inflammatory and immunity-related biological processes and aligned with the distribution of the GABA and noradrenaline neurotransmitter systems. The findings demonstrate that the SA-related functional network of depression is predominantly located at the SCAN, which is an essential implication for understanding depressive patients with SA.

The present study aimed to determine the feasibility of the American College of Radiology's (ACR) contrast‐enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI‐RADS) (version 2017) in examinations using Sonazoid and compare its diagnostic performance with that of modified LI‐RADS in patients at high risk of hepatocellular carcinoma (HCC). This retrospective study's sample population consisted of 137 participants with a total of 140 nodules who underwent CEUS with Sonazoid and pathological confirmation via surgery or biopsy from January 2020 to February 2022. The lesions were evaluated and classified based on the reference standards (ie, ACR CEUS LI‐RADS and modified LI‐RADS). The overall diagnostic capabilities of the two systems were evaluated in terms of accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with 95% confidence intervals (CIs). The participants had a median age of 51 years and an interquartile range of 43–58 years. Regarding LR‐5 as a predictor of HCC, the accuracy results of the ACR LI‐RADS and modified LI‐RADS algorithms were 72.9 and 71.4%, respectively (P= .50). The sensitivity of both systems was the same (69.7%; 95% CI: 60.7–77.8%). Regarding LR‐M as a predictor of non‐HCC malignancy, the diagnostic performance of the algorithms was the same, with accuracy and sensitivity results of 76.4 and 73.3%, respectively (95% CI: 44.9–92.2%). The findings indicate that modified LI‐RADS had a moderate level of diagnostic performance for HCC in examinations using Sonazoid, which was comparable to ACR LI‐RADS.

A straightforward diastereo- and enantioselective Claisen rearrangement/oxa-Michael addition tandem sequence with a cinchona squaramide catalyst was described, which afforded a practical and atom-economical approach to access a range of valuable dihydropyrans in good to excellent yields with excellent stereoselectivities. The organo-bifunctional catalyst played a key role in enhancing stereoselectivity in this asymmetric tandem sequence. Moreover, the asymmetric catalytic sequential processes of the hydroalkoxylation/Claisen rearrangement/cyclization sequence and Claisen rearrangement/aza-Michael addition tandem sequence have also been afforded good yields and moderate stereoselectivities.

Focal epilepsy accounts for 60% of all forms of epilepsy, but the pathogenic mechanism is not well understood. In this study, three novel mutations in NPRL3(nitrogen permease regulator-like 3), c.937_945del, c.1514dupC and 6,706-bp genomic DNA (gDNA) deletion, were identified in three families with focal epilepsy by linkage analysis, whole exome sequencing (WES) and Sanger sequencing. NPRL3 protein is a component of the GATOR1 complex, a major inhibitor of mTOR signaling. These mutations led to truncation of the NPRL3 protein and hampered the binding between NPRL3 and DEPDC5, which is another component of the GATOR1 complex. Consequently, the mutant proteins enhanced mTOR signaling in cultured cells, possibly due to impaired inhibition of mTORC1 by GATOR1. Knockdown of nprl3in Drosophilaresulted in epilepsy-like behavior and abnormal synaptic development. Taken together, these findings expand the genotypic spectrum of NPRL3-associated focal epilepsy and provide further insight into how NPRL3mutations lead to epilepsy.