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With the rapid development of portable electronic devices, there is an urgent need for the multifunctional composites like excellent electromagnetic interference (EMI) shielding performance, mechanical property, and thermal management capabilities. Here, due to the low thermal conductivity of phase change materials (PCMs), a sandwich structure carbon nanotube/phase change microcapsule/carbon nanotube (CNT/PMC/CNT (CPC)) film was prepared by vacuum‐assisted filtration (VAF) method. CNT, PMC, and cellulose nanocrystal (CNC) were used as functional fillers. The addition of CNCs was used to improve the mechanical performance of CPC film. Compared with PMC‐CNC (PC) film, CPC film with sandwich structure prevented leakage phenomenon efficiently. Subsequently, the use of ultrasonic‐assisted forced infiltration (UAFI) successfully infiltrated polydimethylsiloxane (PDMS) matrix in the filler skeleton to obtain CNT/PMC/CNT/PDMS (CPCP) composites. When filler mass ratio (CNT: CNC and PMC: CNC) reached 10:1, the thermal conductivity of CPCP composites was 2.32 W/(m·K) and total EMI shielding effectiveness (EMI SET) of it with 0.38 mm thickness reached 37.46 dB at 12.4 GHz. Besides, these sandwich composites exhibited the good mechanical properties and heat storage capacity. And we systematically observed the impact of different addition amounts of PC homogeneous dispersing solution on phase change ability of CPCP10:1 composites. In summary, CPCP phase change composites with sandwich structure shows potential application prospect in thermal management materials with EMI shielding of electronic devices. Highlight: The sandwich structure CPCP composites prepared by the combination of VAF and UAFI method, showing superior thermal conductivity and phase change ability.CPCP has excellent EMI shielding performance, which can meet the need of TMMs with EMI shielding performance.Compared with same thickness PC film, sandwich CPC film can prevent leakage phenomenon efficiently. [ABSTRACT FROM AUTHOR]

Biochar is an efficacious amendment for mitigating nitrous oxide (N2O) emissions in soils. Nevertheless, the underlying mechanisms responsible for reduced N2O emissions by biochar in paddy soils remain inadequately elucidated. Here, using two typical paddy soils with contrasting pH values (5.40 and 7.56), the N2 and N2O fluxes and the associated functional genes were investigated in soil amended with varying amounts of biochar (0%, 0.5%, and 5%, weight/weight) via soil slurry incubation integrated with the N2/Ar technique and qPCR analysis. The results showed that N2O fluxes were significantly (p < 0.05) reduced by 0.65–3.64 times following biochar amendment, concomitant with a significant (p < 0.05) increase in N2 fluxes (5.47–46.14%) in both acidic and alkaline paddy soils. As a result, the N2O/(N2O + N2) ratios were significantly (p < 0.05) reduced by 1.53–4.65 fold in both soil types. In acidic paddy soils, the enhanced denitrification rates and the decreased N2O/(N2O + N2) ratios exhibited a strong correlation with increased pH values. In alkaline paddy soil, these changes were ascribed to the enhanced nosZ Clade I gene abundance and nosZ/(nirS + nirK) ratio. Our findings reveal that biochar primarily mitigates N2O emissions in paddy soils by promoting its reduction to N2. [ABSTRACT FROM AUTHOR]

Recognizing a face as belonging to a given identity is essential in our everyday life. Clearly, the correct identification of a face is only possible for familiar people, but 'familiarity' covers a wide range—from people we see every day to those we barely know. Although several studies have shown that the processing of familiar and unfamiliar faces is substantially different, little is known about how the degree of familiarity affects the neural dynamics of face identity processing. Here, we report the results of a multivariate EEG analysis, examining the representational dynamics of face identity across several familiarity levels. Participants viewed highly variable face images of 20 identities, including the participants' own face, personally familiar (PF), celebrity and unfamiliar faces. Linear discriminant classifiers were trained and tested on EEG patterns to discriminate pairs of identities of the same familiarity level. Time‐resolved classification revealed that the neural representations of identity discrimination emerge around 100 ms post‐stimulus onset, relatively independently of familiarity level. In contrast, identity decoding between 200 and 400 ms is determined to a large extent by familiarity: it can be recovered with higher accuracy and for a longer duration in the case of more familiar faces. In addition, we found no increased discriminability for faces of PF persons compared to those of highly familiar celebrities. One's own face benefits from processing advantages only in a relatively late time‐window. Our findings provide new insights into how the brain represents face identity with various degrees of familiarity and show that the degree of familiarity modulates the available identity‐specific information at a relatively early time window. Familiarity degree affects face identity processing. We studied the representational dynamics of face identity for self, personally familiar, celebrity and unfamiliar faces. Identity information emerged around 100 ms, independently of familiarity while it was recovered better and longer for more familiar faces between 200 and 400 ms. We show how the degree of familiarity modulates the available identity‐specific information. [ABSTRACT FROM AUTHOR]

The amyloid‐β (Aβ) peptide, produced from amyloid precursor protein (APP) by β and γ‐secretases, has been implicated in the etiology of Alzheimer's disease (AD). However, the precise intracellular trafficking pathway of APP and its subcellular locations to produce Aβ have remained unclear. To address these issues, we established fly AD models that recapitulated multiple AD‐like symptoms by expressing human APP in the Drosophila nerve system. The ESCRT (endosomal sorting complexes required for transport) machinery regulates the sorting and trafficking of endocytosed proteins, yet its role in AD pathogenesis has not been explored in vivo. We found that knockdown of distinct ESCRT components ameliorated APP‐induced morphological and behavioral defects, including impaired wing expansion, eye degeneration, dopamine neuron loss, locomotor disability, lifespan shortening, and cognitive deficits. Mechanistically, we showed that impaired ESCRT impeded APP's intracellular transportation from early endosomes to late endosomes, resulting in reduced Aβ production and amyloid deposit load. These data suggest that APP undergoes ESCRT‐mediated endocytic trafficking, and Aβ is generated mainly in late endosomes. Our data provide the first in vivo evidence to support a physiological role of ESCRT in AD pathogenesis, suggesting that interfering with ESCRT machinery might be an alternative therapeutic strategy for AD. [ABSTRACT FROM AUTHOR]

Thermoelectric‐photoelectric integrated power generator and a power management circuit are designed in this letter for the inefficiency of power amplifier and the generation of massive heat of transceiver. Thermoelectric‐photoelectric integrated power generator is composed of thermoelectric power generator at surface layer and photoelectric power generator at bottom layer, absorbing both heat and light energy at the same time. The outputs of thermoelectric and photoelectric power generator are connected with power management circuit after parallel connection. Power management circuit is an interface circuit which is able to boost the small output voltage of integrated power generator from 300 mV to 3.1 V with no external power supply. The innovation is not only structure integration, but also output integration of two power generators. In addition, 3.1 V voltage from power management circuit is compatible with most interfaces in transceiver system. The integrated power generator and power management circuit form a complete power supply module for transceiver and wireless sensor node. [ABSTRACT FROM AUTHOR]

This article presents a self‐reference algorithm to improve the accuracy of micro‐electro‐mechanical system thermoelectric microwave power sensor (5‐15 GHz). The output thermovoltage of the sensor is not only a function of the input signal power, but also relates to the signal frequency, resulting in low accuracy of the sensor. In this article, a mathematical model is established for the sensor to analyze the reasons for frequency dependence. Moreover, an algorithm is derived from analyzing the characteristics of the model and the experimental results. The algorithm relieves the dependence on the thermovoltage and frequency. Experiments show that the relative error of the sensor based on the proposed self‐reference algorithm decreases from 22% to 1.6%, and the SD is smaller than 0.4 mW. This self‐reference algorithm plays critical role in the practical application of microwave power sensors. [ABSTRACT FROM AUTHOR]

An MEMS microwave power sensor with thermovoltage compensation and transformation is presented. The sensor obtains a thermovoltage which is linear to the input power, thanks to the Seebeck effect. However, the thermovoltage decreases as the frequency of input power increases due to the loss. The novelty is that the variation of thermovoltage has been compensated by an algorithm, and a transformation line is obtained to transform the thermovoltage to measured power displayed on liquid crystal display. The result indicates that the relative error is smaller than 1.5%. This system has practical applications in precise power measuring instruments. [ABSTRACT FROM AUTHOR]

The study of aging and neurodegenerative processes in the human brain requires a comprehensive understanding of cytoarchitectonic, myeloarchitectonic, and vascular structures. Recent computational advances have enabled volumetric reconstruction of the human brain using thousands of stained slices, however, tissue distortions and loss resulting from standard histological processing have hindered deformation‐free reconstruction. Here, the authors describe an integrated serial sectioning polarization‐sensitive optical coherence tomography (PSOCT) and two photon microscopy (2PM) system to provide label‐free multi‐contrast imaging of intact brain structures, including scattering, birefringence, and autofluorescence of human brain tissue. The authors demonstrate high‐throughput reconstruction of 4 × 4 × 2cm3 sample blocks and simple registration between PSOCT and 2PM images that enable comprehensive analysis of myelin content, vascular structure, and cellular information. The high‐resolution 2PM images provide microscopic validation and enrichment of the cellular information provided by the PSOCT optical properties on the same sample, revealing the densely packed fibers, capillaries, and lipofuscin‐filled cell bodies in the cortex and white matter. It is shown that the imaging system enables quantitative characterization of various pathological features in aging process, including myelin degradation, lipofuscin accumulation, and microvascular changes, which opens up numerous opportunities in the study of neurodegenerative diseases in the future. [ABSTRACT FROM AUTHOR]

Exudate management and bioelectric signals are critical to promoting wound healing. In this study, the thermoplastic polyurethane (TPU) nanofiber is directly electrospun on the cotton microfibers (Cotton) to prepare a Janus dressing (TPU/Cotton), which can unidirectionally drain the excess exudate. Then, Ag/Zn dot electrodes are deposited on the TPU layer, which can produce an electric field penetrating the wound when activated by wound exudate. The hydro‐activated Ag/Zn's electrical stimulation (ES) can promote the migration of fibroblast cells and shows excellent antibacterial activity against E. coli and S. aureus. Furthermore, in vivo experiments show that the exudate management coupled with ES accelerated wound healing at multiple stages by promoting re‐epithelization, collagen deposition, and vascularization. Moreover, the Ag/Zn@TPU/Cotton dressing shows excellent biocompatibility in the vitro cytotoxicity experiments. These findings may shed some light on developing the next generation of wound dressings with self‐activated electrical stimulation and exudate management. [ABSTRACT FROM AUTHOR]

Objectives: The evolutionary conserved JNK pathway plays crucial role in cell death, yet factors that modulate this signalling have not been fully disclosed. In this study, we aim to identify additional factors that regulate JNK signalling in cell death, and characterize the underlying mechanisms. Materials and Methods: Drosophila were raised on standard media, and cross was carried out at 25°C. The Gal4/UAS system was used to express proteins or RNAi in a specific temporal and spatial pattern. Gene expression was revealed by GFP fluorescence, X‐gal staining or immunostaining of 3rd instar larval eye and wing discs. Cell death was visualized by acridine orange (AO) staining. Images of fly eyes and wings were taken by OLYMPUS microscopes. Results: We found that licorne (lic) encoding the Drosophila MKK3 is an essential regulator of JNK‐mediated cell death. Firstly, loss of lic suppressed ectopic Egr‐triggered JNK activation and cell death in eye and wing development. Secondary, lic is necessary for loss‐of‐cell polarity‐induced, physiological JNK‐dependent cell death in wing development. Thirdly, Lic overexpression is sufficient to initiate JNK‐mediated cell death in developing eyes and wings. Furthermore, ectopic Lic activates JNK signalling by promoting JNK phosphorylation. Finally, genetic epistatic analysis confirmed that Lic acts in parallel with Hep in the Egr‐JNK pathway. Conclusions: This study not only identified Lic as a novel component of the JNK signalling, but also disclosed the crucial roles and mechanism of Lic in cell death. [ABSTRACT FROM AUTHOR]

Chrysin (CHR) is a flavonoid with extensive pharmacological activity. The molecular formula of CHR is C15H10O4. CHR is reported to have antioxidative, antitumour and antiviral functions. To evaluate its potential function as a vaccine adjuvant, we prepared a melanoma vaccine using a soluble protein extract of B16F10 melanoma cells as antigen and CHR as an adjuvant. The melanoma model was developed after two immunizations, and it was discovered that combining B16F10 soluble protein antigen‐mixed CHR vaccine could inhibit tumour growth in the mouse model, and the overall survival rate was higher than that of the B16F10 antigen vaccine alone. In vivo and in vitro experiments were conducted to determine whether CHR functioned as an adjuvant by activating antigen‐presenting cells (APCs). We discovered that CHR activated APCs both in vivo and in vitro and may enhance Th1 cell function by activating the IL12‐STAT4 signal pathway, thereby enhancing the antitumour response of cytotoxic T lymphocytes (CTLs) in vivo. Next, to verify the critical role of CD8+ T cells in suppressing melanoma development, we transplanted CD8+ T cells from immunized mice to B16F10 tumour‐bearing mice and discovered that the survival rate of tumour‐bearing mice was significantly prolonged. In summary, our experimental results indicate that CHR can be used as a potential adjuvant to enhance antigen immunogenicity, inhibit B16F10 tumour growth in mice and improve tumour immune response. [ABSTRACT FROM AUTHOR]

Noninvasive and real-time cuffless blood pressure (BP) measurement realizes the idea of unobtrusive and continuous BP monitoring which is essential for diagnosis and prevention of cardiovascular diseases associated with hypertension. In this paper, a wearable sensor patch system that integrates flexible piezoresistive sensor (FPS) and epidermal electrocardiogram (ECG) sensors for cuffless BP measurement is presented. By developing parametric models on the FPS sensing mechanism and optimizing operational conditions, a highly stable epidermal pulse monitoring method is established and beat-to-beat BP measurement from the ECG and epidermal pulse signals is demonstrated. In particular, this study highlights the compromise between sensor sensitivity and signal stability. As compared with the current optical-based cuffless BP measurement devices, the sensing patch requires much lower power consumption (3 nW) and is capable of detecting subtle physiological signal variations, e.g., pre and postexercises, thus providing a promising solution for low-power, real-time, and home-based BP monitoring. [ABSTRACT FROM AUTHOR]

Adhesive patches are advanced but challenging alternatives to suture, especially in treating fragile internal organs. So far there is no suture‐free adhesive patch based on metabolizable poly(amino acid) materials with excellent mechanical strength as well as immunomodulation functionality. Here, a polyglutamic acid‐based elastic and tough adhesive patch modified by photosensitive groups on the surface to achieve robust light‐activated adhesion and sealing of flexible internal organs is explored. With the porous internal morphology and excellent biodegradability, the patches promote regeneration through a macrophage‐regulating microenvironment. Treated rabbits achieve rapid full‐thickness gastric regeneration with complete functional structure within 14 d, suggesting its robust tissue adhesion and repair‐promoting ability. [ABSTRACT FROM AUTHOR]

In the present work, a new electrochemical strategy for the sensitive and specific detection of soluble β-amyloid Aβ(1-40/1-42) peptides in a rat model of Alzheimer's disease (AD) is described. In contrast to previous antibody-based methods, β-amyloid(1-40/1-42) was quantified based on its binding to gelsolin, a secretory protein present in the cerebrospinal fluid (CSF) and plasma. The level of soluble β-amyloid peptides in the CSF and various brain regions were found with this method to be lower in rats with AD than in normal rats. [ABSTRACT FROM AUTHOR]

In the present work, a new electrochemical strategy for the sensitive and specific detection of soluble β-amyloid Aβ(1-40/1-42) peptides in a rat model of Alzheimer's disease (AD) is described. In contrast to previous antibody-based methods, β-amyloid(1-40/1-42) was quantified based on its binding to gelsolin, a secretory protein present in the cerebrospinal fluid (CSF) and plasma. The level of soluble β-amyloid peptides in the CSF and various brain regions were found with this method to be lower in rats with AD than in normal rats. [ABSTRACT FROM AUTHOR]

We have developed a two‐step protocol for iodotrimethylsilane‐mediated deoxy‐functionalization of primary and secondary alcohols to afford products containing a C−N, C−S, or C−O bond. In the first step the alcohol undergoes iodination with iodotrimethylsilane, and in the second, the iodine atom is replaced by a N, S, or O nucleophile. Compared with traditional Mitsunobu reaction, non‐acidic pre‐nucleophiles can be used, and the reaction proceeds with retention of configuration. This operationally simple, highly efficient protocol can be used for some natural products and small‐molecule drugs containing hydroxy‐group. [ABSTRACT FROM AUTHOR]

N. Zhao and coworkers demonstrate, on page 1178, a low‐power, wearable sensor system that integrates a flexible piezoresistive sensor and epidermal electrocardiogram sensors, for extracting real‐time beat‐to‐beat blood pressure measurements. Through parametric modelling and operation optimization, highly stable epidermal pulse monitoring is achieved, and the compromise between sensor sensitivity and signal stability is highlighted. [ABSTRACT FROM AUTHOR]

Wearable pressure sensors enable long‐term real‐time health monitoring in a noninvasive and power‐efficient way; however, the sensors are often required to be precisely applied at the optimal measurement spot, e.g., nearby radial artery, for signal acquisition, causing inconvenience for untrained users or the elders. In this paper, a wearable liquid‐capsule sensor platform embedded with a piezo‐resistive pressure sensor is presented for continuous, accurate, and alignment‐relaxed physiological monitoring, i.e., heart rate (HR) and blood pressure (BP) tracking. The flexible capsule design ensures comfort and good device conformation to any skin regions. For HR and BP measurements, experiments are performed on 12 human subjects. The results show that the capsuled sensor can continuously track: 1) HR with a mean absolute difference (MAD) of 0.88 beats per minute (bpm) and 2) BP with a MAD<3 mmHg for both diastolic and systolic blood pressure. The new liquid‐capsule‐based sensor platform may help to realize an accurate, flexible, robust, and low‐power solution for next‐generation wearable health monitoring devices. A wearable liquid‐capsule sensor platform embedded with a piezo‐resistive pressure sensor for continuous, accurate, and alignment‐relaxed physiological monitoring, i.e., heart rate and blood pressure tracking, is realized. [ABSTRACT FROM AUTHOR]