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The tunable bandgaps of metal halide perovskites lead to their promising application in indoor photovoltaics (IPVs). However, perovskites with wide bandgaps suitable for indoor light typically have lower conductivity and higher defect density, which leads to inefficient charge transport and extraction, limiting their photovoltaic performances. Herein, we investigated the IPV characteristics of triple-cation perovskites with varying bandgaps by tailoring the Br/I ratios. We found that wide-bandgap perovskites could effectively utilize indoor light and achieve high open circuit voltage values under low illumination conditions. However, increasing the Br/I ratios results in higher defect density, leading to decreased short-circuit current density and fill factor. We thoroughly studied the crystallization dynamics, defect density, and charge transfer properties of triple-cation perovskites with varying bandgaps. We found the prevailing concept that efficient IPVs taking the bandgap of IPV materials into special consideration was not comprehensive. We demonstrate that IPV devices with superior IPV properties can be developed by appropriately reducing the Br contents in wide-bandgap crystals. In other words, the preparation of IPV crystal materials should consider both the bandgap and charge transport characteristics. In this work, we obtained devices with the optimal efficiency of 40.71% under 1035 lux LED illumination by achieving a balance between bandgap and charge transfer (Br 0.23, 1.62 eV). This research provides valuable insights for the design of efficient IPVs.

The cold-start problem in recommender systems has been facing a great challenge. Cross-domain recommendation can improve the performance of cold-start user recommendations in the target domain by using the rich information of users in the source domain. In cross-domain cold-start recommendation, users in target domain lack sufficient historical behaviors. Existing meta-learning-based methods depend on the feature distribution of training data and limit the adaptability in new tasks. To address these issues, we propose a meta-adversarial framework for cross-domain cold-start recommendation (MAFCDR) . Specifically, we employ a multi-level feature attention mechanism for independently learning the weights of long-term and short-term features to construct preferences of users in source domain. To migrate user representations, we train a meta-adversarial network that utilizes feature embeddings in the source domain as input and enhances the robustness and stability of the model. Then, the personalized bridge function transfers the user preferences in the source domain to the target domain. We build three cross-domain tasks using Amazon dataset and conduct extensive experiments, which demonstrate the effectiveness of the proposed model in cold-start user recommendation.

Accidental and symmetry-protected bound states in the continuums (BICs) generated by different triggering mechanisms have been demonstrated to hold great promise for confining light waves within the nanoscale. These BIC modes offer an elegant solution for manipulating the quality ( ${Q}$ ) factor, which is a primary performance index for devices relying on dielectric nanostructures. Here, using dielectric metasurfaces above a metal substrate, three eigenmodes are investigated, one of which corresponds to an accidental BIC with in-plane magnetic dipole (MD) characteristics, while the other two correspond to symmetry-protected BICs with out-of-plane electric dipole (ED) characteristics. Through parameter adjustment, the BICs can transition into high- ${Q}$ quasi-BICs that can simultaneously achieve perfect absorption. The metasurface exhibits considerable potential as a sensor, showcasing a maximum sensitivity of 374.7 nm/RIU and a maximum figure of merit of 72 RIU−1 within the sensing refractive index range of 1–1.1. In the context of temperature sensing, the sensitivity can reach up to 0.845 nm/°C within the sensing temperature range of 20 °C–100 °C. Our work will open a new avenue for the study of refractive index and temperature sensors with ultrahigh sensitivity.

This article presents an optical fiber vibration sensor with a wide detection range based on the Mach–Zehnder interference principle, which is composed of single-mode fiber (SMF), two-mode step index fiber (TMSIF), and dispersion-compensated fiber (DCF) fused, and the optical fiber sensing structure fused is SMF-TMSIF-DCF-SMF, abbreviated as STDS sensor. In this work, the single-frequency response and dual-frequency response of this sensor are tested, and the test results indicate that the sensor can stably measure the extended single-frequency response in the range of 1–23000 Hz (the maximum signal-to-noise ratio (SNR) is 61.2 dB) and the dual-frequency response. In addition, the amplitude-frequency response test results reveal a good linear relationship between the fast Fourier transform (FFT) amplitude and the vibration amplitude. Subsequently, a temperature test was performed on the sensor in the range of 25 °C–65 °C, and it was found that the spectral intensity shift induced by temperature was only 0.03501 dB/°, and the measured frequency was consistent with the applied frequency. Finally, the stability and repeatability tests were carried out on the sensor; the stability test results proved that the sensor measured consistently and without deviations for 60 min, and the repeatability test proved that the sensor could measure consistently for more than 40 days and that the measurement results were accurate. The sensor has the advantages of a wide detection range (the frequency measurement range is 1–23000 Hz), excellent anti-interference to temperature fluctuations, reusability, and so on, and has great application prospects in various vibration signal monitoring.

We proposed a novel, temperature-insensitive, low-cost multipoint displacement sensing system. The system includes three parts: fiber displacement sensor, fiber loop mirror (FLM), and optical time-domain reflectometer (OTDR). The fiber displacement sensor is designed by cascading single-mode-no-core-single-mode (SNS) fiber, and the SNS is attached to FLM that is constructed by a 3-dB coupler to improve the measurement dynamic range. The variation of displacement will significantly change the value of SNS macro-bending loss, which causes the variation of FLM reflected energy to achieve displacement measurement. Each FLM constitutes a displacement sensing unit, and only 5% pulsed light energy is input for each sensing unit to increase the number of reusable sensors. The results show that each sensor can maintain a similar sensing effect, and the measurement dynamic range can reach 15.613 dB. The peak energy of each FLM is almost unaffected by changes in the external temperature. The proposed system is an ideal solution to engineering problems of displacement measurement, which can be widely used in the field of structural health monitoring.

Fiber optic (FO) sensors have great potential for low-cost, microsample testing and compact medical diagnostics. In this work, a FO sensor based on dielectric nanostructure is proposed and demonstrated based on the unique characteristics of dielectric materials, such as low ohmic loss and good biocompatibility. Specifically, we fabricate a SPR-FO sensor by inserting a sleeve with a large-scale, highly ordered dielectric nanodisk array at the end of the fiber probe. And we systematically investigate the sensing performance of the FO sensor including bulk and surface sensitivities. It is found that due to very low absorption losses, the FO sensor based on dielectric nanodisk exhibits a narrow resonance, thus leading to a sensing figure-of-merit almost twice larger than that of based on the metal plasmonic nanodisk. Also, the FO sensor shows a linear response to adsorbate layer thickness changes, which is clearly advantageous for quantitative analysis. Due to the highly localized electromagnetic fields, it can detect small molecules with a concentration of 1 μM, in which a molecular layer with thickness less than 1 nm can produce resonance changes as large as 6 nm. Our work could open a new opportunity for future bio-compatible, robust and low-loss medical diagnostic devices.

Vibration detection plays a vital role in the safety monitoring of engineering areas such as structural deformation of large buildings and railway tracks, and oil and gas spills. Herein, a temperature-insensitive optical fiber vibration sensor based on Mach–Zehnder interference is proposed and validated, which is achieved by utilizing a dispersion-compensated fiber (DCF). Specifically, single-mode fiber (SMF) is fused to both ends of a DCF to form an optical fiber vibration sensor, which is SMF–DCF–SMF (SDS) sensor. Under this sensing structure, this sensor’s vibration sensing characteristics, amplitude–frequency response, stability, repeatability, and temperature-insensitive characteristics are investigated. The sensor can measure vibration frequency signals in the large frequency range of 0.1 Hz–47 kHz by intensity demodulation. When the vibration frequency is 600 Hz, the maximum signal-to-noise ratio (SNR) of the sensor reaches 69 dB. In addition to that, the sensor can capture low-amplitude vibration frequency signals down to 0.01 V. The proposed sensor has a wide measurement frequency range that effectively reduces temperature cross-sensitivity, and it has the advantage of being compact, low cost, and easy to manufacture, with potential applications in health inspections, machinery, and building saturation.

A fast emissivity measuring apparatus in the range of 1.4– $2.5 \mu \text{m}$ with adjustable focusing and field calibration has been developed in this article. Benefiting from the portable, fast, and efficient characteristics of the fiber optic spectrometer, the rapid in situ emissivity measurement in industry, such as aluminum profile casting or molten-salt monitoring, can be realized by this apparatus. The light path system of this apparatus is designed based on the principle of the Newtonian reflecting telescope, and the relationship between the radiation signal and the object distance is analyzed in detail. The focus adjustment of the apparatus improves the radiation entering the system, thus ensuring that the measurement signal does not decrease rapidly with the increase in distance. The emissivity of silicon carbide (SIC) and pure silicon is calculated by the Fresnel formula and the results of measured emissivity by the apparatus are in good agreement with the data of theoretical calculation, which verifies the reliability of the apparatus. The maximum error of calibrated radiation of this apparatus is not more than 2.5%, and the average error is less than 1% in the wavelength range of 1.4– $2.5 \mu \text{m}$ . In a feasibility test, the relative combined uncertainty of the spectral emissivity of SIC is less than 5.73%.

Perovskite light-emitting diodes (PeLEDs) with an external quantum efficiency exceeding 20% have been achieved in both green and red wavelengths1–5; however, the performance of blue-emitting PeLEDs lags behind6,7. Ultrasmall CsPbBr3quantum dots are promising candidates with which to realize efficient and stable blue PeLEDs, although it has proven challenging to synthesize a monodispersed population of ultrasmall CsPbBr3quantum dots, and difficult to retain their solution-phase properties when casting into solid films8. Here we report the direct synthesis-on-substrate of films of suitably coupled, monodispersed, ultrasmall perovskite QDs. We develop ligand structures that enable control over the quantum dots’ size, monodispersity and coupling during film-based synthesis. A head group (the side with higher electrostatic potential) on the ligand provides steric hindrance that suppresses the formation of layered perovskites. The tail (the side with lower electrostatic potential) is modified using halide substitution to increase the surface binding affinity, constraining resulting grains to sizes within the quantum confinement regime. The approach achieves high monodispersity (full-width at half-maximum = 23 nm with emission centred at 478 nm) united with strong coupling. We report as a result blue PeLEDs with an external quantum efficiency of 18% at 480 nm and 10% at 465 nm, to our knowledge the highest reported among perovskite blue LEDs by a factor of 1.5 and 2, respectively6,7.

Optical cavities supporting the optical bound states in the continuum (BICs) with infinite radiative lifetime have recently been widely reported. Here, we theoretically investigate BICs in an ultrathin photonic structure consisting of a multilayer, nanostructured transition metal dichalcogenide (TMD). Using finite element simulations, we demonstrate two distinct groups of BICs, namely symmetry-protected BICs and interference-based BICs, in the photonic system. Under normal incidence, their dispersion can be mediated by altering the grating pitch, which makes it possible to explore the strong coupling of these two photonic modes with the TMD exciton band in the same structure. This work expands not only the library of traditional nanophotonic approaches, but also provides more possibilities for optoelectronic devices toward miniaturization.

An animal’s nervous system changes as its body grows from birth to adulthood and its behaviours mature1–8. The form and extent of circuit remodelling across the connectome is unknown3,9–15. Here we used serial-section electron microscopy to reconstruct the full brain of eight isogenic Caenorhabditis elegansindividuals across postnatal stages to investigate how it changes with age. The overall geometry of the brain is preserved from birth to adulthood, but substantial changes in chemical synaptic connectivity emerge on this consistent scaffold. Comparing connectomes between individuals reveals substantial differences in connectivity that make each brain partly unique. Comparing connectomes across maturation reveals consistent wiring changes between different neurons. These changes alter the strength of existing connections and create new connections. Collective changes in the network alter information processing. During development, the central decision-making circuitry is maintained, whereas sensory and motor pathways substantially remodel. With age, the brain becomes progressively more feedforward and discernibly modular. Thus developmental connectomics reveals principles that underlie brain maturation.

A tunable fiber optic (FO) long‐range surface plasmon (LRSP) sensor with strong coupling is developed and demonstrated theoretically in this article. The sensor consists of a square lattice array of Ag nanodisks resting on the FO end face. Utilizing nanodisks with small diameters leads to the pronounced excitation of two distinct and independent resonant modes: surface plasmon polaritons (SPP) and LRSP. A systematic investigation is performed to evaluate the sensing performance and capabilities of the sensor, focusing on its bulk and surface sensitivity. Significantly, the LRSP mode demonstrates high sensitivity and favorable linearity in response to refractive index (RI) changes, with an exceptionally high figure of merit (FOM). On the contrary, the SPP mode is regarded as an ideal self‐referencing mode due to its immunity to RI fluctuations. The enlargement of nanodisks diameters results in a swift redshift in the LRSP wavelength, leading to a strong coupling with the SPP mode. This coupling facilitates the transfer of electric fields within the SPP mode, promotes sensing capabilities, and enables the realization of dual‐channel sensing functionality. The occurrence of strong coupling phenomena along with the use of FO substrates provides an innovative option for achieving multifunctionality and miniaturization in sensor platforms. A tunable fiber optic long‐range surface plasmon sensor strongly coupled with surface plasmon polaritons is proposed which features dual‐channel, self‐referential sensing with high bulk and surface sensitivity, figure of merit, and noise immunity and provides an innovative option for achieving multifunctionality and miniaturization in sensor platforms.

Multi-wavelength radiometric thermometry has a wide application prospect in many fields. However, due to unknown emissivity, the data processing algorithm remains a difficult problem. The Broyden–Fletcher–Goldfarb–Shanno (BFGS) algorithm is proposed to inverse true temperature and spectral emissivity without assuming the emissivity model. The BFGS algorithm can automatically identify the emissivity models of different trends. These simulation results show that given different initial emissivity has no significant influence on the inverse temperature and emissivity. Then, we select 0.5 as the initial emissivity and carry out the simulation experiments at 800 and 900 K, respectively. The maximum absolute error of temperature is less than 3.5 K and the computation time is less than 0.2 s. Thus, the algorithm has high precision and efficiency. Finally, the verification experiment indicates that the BFGS algorithm is effective and reliable. The proposed method can be applied to real-time temperature measurement in many industrial processes.

Background: At present, the main problems of Micro-Electro-Mechanical Systems (MEMS) based temperature detector are the narrow range of temperature detection and difficulty in the measurement of high temperature. Besides, MEMS devices have different response characteristics for various surrounding temperature in the petrochemical and metallurgy application fields with hightemperature and harsh conditions. To evaluate the performance stability of the high-temperature MEMS devices, the real-time temperature measurement is necessary. Objective: A Schottky temperature detector based on the metal/n-ZnO/n-Si structures is designed to measure high temperature (523~873K) for MEMS devices with a large temperature range. Methods: By using the Finite Element Method (FEM), three different work function metals (Cu, Ni and Pt) contacting the n-ZnO were investigated to realize Schottky. At room temperature (298K) and high temperature (523~873K), the current densities with various bias voltages (J-V) were studied. Results: The simulation results show that the high-temperature response power consumption of three Schottky detectors of Cu, Ni and Pt decreases successively, which is 1.16 mW, 63.63 μW and 0.14 μW. The response temperature sensitivities of 6.35 μA/K, 0.78 μA/K, and 2.29 nA/K are achieved. Conclusion: The Cu/n-ZnO/n-Si Schottky structure could be used as a high-temperature detector (523~873K) for the high-temperature MEMS devices. It has a large temperature range (350K) and a high response sensitivity of 6.35 μA/K. Compared with the traditional devices, the Cu/n-ZnO/n-Si Schottky structure-based temperature detector has a low energy consumption of 1.16 mW, having potential applications in the high-temperature measurement of the MEMS devices.

A robust fogwater harvester with an elastic microstaggered porous superhydrophilic framework (EMSF) has been designed. The EMSF can be fabricated by using polydimethylsiloxane and polyvinyl alcohol (PVA) via an etching method of sugar crystals pile-up cube as a template. The EMSF possesses a high porosity of 76%, of which the saturated fogwater-capturing capacity is 4 times higher than its weight, achieving a high fogwater harvesting rate (ε) of 62.7 g/cm3·h. It is attributed to the strong hydrogen bond (H-bond) interaction between hydroxyl groups (−OH) in PVA and water molecules for rapidly harvesting water and storing water in a staggered porous structure by means of a capillary force. The elasticity of EMSF allows to achieve a higher fogwater harvesting rate (ε) of 73.2 g/cm3·h via releasing the as-stored water in the EMSF under periodic external pressing. In addition, a durable corrosion resistance is demonstrated on the EMSF. This study offers a way to design novel materials that would further be extended into applications, for example, fog engineering in industry, agriculture, forest, and so forth.

ABSTRACTThis study aimed to determine the WNT2 expression in patients with severe preeclampsia and to explore the function of WNT2 dysregulation on the biological behaviors of trophoblast cells. The WNT2 and β-catenin expression in the patients with early-onset and late-onset severe preeclampsia and normal controls was determined. Subsequently, WNT2 was overexpressed and knocked down in HTR8 cells and WNT2 signaling pathway in regulating trophoblast cell proliferation, migration, invasion, and apoptosis were evaluated in vitro. The mRNA and protein expression levels of WNT2 and β-catenin were decreased in patients with preeclampsia, especially early-onset severe preeclampsia. Overexpression of WNT2 promoted trophoblast cell proliferation, migration, and invasion and inhibited apoptosis in vitro, whereas knockdown of WNT2 had opposite effects. The findings of this study reveal that WNT2 and β-catenin were decreased expressed in patients with preeclampsia. Decreased expression of WNT2 may inhibit trophoblast cell proliferation, migration, and invasion but induced apoptosis. WNT2 may serve as a promising biomarker for early detection of preeclampsia.

A single-molecule-level understanding of the activity of solvating water molecules in hydrogen-bonded assemblies would provide insights into the properties of the first hydration shells. Herein, we investigate the solvation of one of the DNA bases, cytosine, whose glassy-state network formed on Au(111) contains diverse types of hydrogen-bonded dimer configurations with hierarchical strengths. Upon water exposure, a global structural transformation from interwoven chain segments to extended chains was identified by scanning tunneling microscopy and atomic force microscopy. Density functional theory calculation and coarse-grained molecular dynamics simulation indicate that water molecules selectively break the weak-hydrogen-bonded dimers at T-junctions, while the stable ones within chains remain intact. The resulting hydrated chain segments further self-assemble into molecular chains by forming strong hydrogen bonds and spontaneously releasing water molecules. Such an intriguing transformation cannot be realized by thermal annealing, indicating the dynamic nature of water molecules in the regulation of hydrogen bonds in a catalytic manner.

Bioinspired nanofibril-humped fibers (BNFs) are fabricated by using thermoplastic polyester elastomer and chitosan, via combining the electrospinning technique and fluid coating method to achieve periodic humps composed of interlaced random nanofibrils and a joint composed of aligned nanofibrils, which are highly similar to the micro/nanostructures of wetted spider silk. Especially, nanofibrils can increase the specific area of the hump to capture fog droplets effectively and transport water in channels between the nanofibrils under humid conditions, and thus the fog droplets can coalesce and be highly efficiently transported toward humps for water collection directionally. Such an ability of highly efficient fog capture is attributed to cooperation of an efficient transportation inside the outer shell of BNFs and outside transportation. Inside transportation is induced by anisotropic capillary channels between nanofibrils. When BNFs are wetted, the inside transportation mode is dominated for water collection, induced by anisotropic capillary channels between nanofibrils. BNF web is also used to investigate the droplet transportation in different cross-fiber contact modes in the process of fog capture on a large scale. This study offers an insight into the design of novel materials, which is expected to be developed for some realms of applications, such as fog harvesting engineering, filtration, and others.

Because of the scarcity of freshwater resources, fog collection as one of the effective methods to solve this issue has attracted widespread concern. Inspired by several natural creatures with the capability to collect water from fog, the bio-inspired water-harvesting materials have aroused considerable attention and been widely developed. Inspired by the directional water droplets transportation to the apex on both shorebirds beaks and wheat awns, the bio-inspired topological alloy net with a V-shaped asymmetric geometry in its mesh was designed for fog collecting. Then, micro-/nano-hierarchical structures were modified on the surface of the netting wire via the cathodic electrodeposition method. Thus, the bio-inspired topological alloy net with micro/nanostructures was fabricated successfully. Through the integration of topological geometry and surface microstructure, not only the water-collection rate is improved by efficient drainage along the designated pathways, but also the issue of mesh clogging is resolved. In addition, a theoretical model was constructed to reveal the mechanism, especially the resultant force arising from the V-shaped structure. This work provides insight into the development of novel fog-collecting materials, which has potential applications in other fields, such as liquid transportation, microfluidics, and interface science.

In this paper, we propose and demonstrate a dual-channel self-calibration multimode optical-fiber surface plasmon resonance thermometer. The structure of this thermometer is mainly composed by dual sensing channels, in which one channel is coated with a gold layer surrounded by liquid crystal (LC), and the other is prepared with bilayers of silver and thin indium tin oxide (ITO) layer. The gold channel is the main channel, and the channel of the ITO layer with high refractive index is viewed as a configuration of self-calibration. The experimental results of the system show that the temperature sensitivities are 1.006 nm/°C in the range of 20°C–34°C and 0.058 nm/°C in the range of 35°C–80°C. In particular, at the phase transition temperature 34.5°C of changing from the nematic to the isotropic phase of the LC, the temperature sensitivity shows a step increase of 6.8 nm with a unit temperature change. This structure can be highly advantageous for temperature controlling and alarming in laboratory monitoring and industrial production.

The bioinspired nanocone-decorated three-dimensional fiber network (N3D) can be fabricated, where an original 3D web is designed, inspired by some newest research findings of spider web, and it is decorated with hydrophilic zinc oxide (ZnO) nanocones inspired by cactus spine. Multilevel high specific surface area exposure on fiber together with the hydrophilic decoration enables it to be more attractive to water molecules. These nanocones can capture fog droplet, generate coalesced droplet, and accordingly make droplet transport efficient because of Laplace pressure difference. Especially, a novel mechanism revealed that after the nanocone-decorated fiber was wetted, that is, a water film formed and immediately broke up into droplets, owing to the force relating to Rayleigh instability. Consequent lower retention surface realizes the formation of fast continuous water flow, rather than the traditional intermittent course. Thus, outstanding fog-harvesting efficiency was achieved on N3D, for example, probably reaching 865.1 kg/m2/day, where the mass of collected water within 2 h can raise up to over 240 times higher than the weight of an original 3D web without nanocones. Such a bioinspired ZnO nanocone-decorated 3D fiber network (i.e., N3D) has potential application to harvest fog water for production or living, for example, water recondensation in cooling water towers and in agricultural irrigation systems, even in water-deficient countries.

In this report, antifouling polyacrylonitrile (PAN) ultrafiltration membranes were prepared from blends of PAN/polyglycidyl methacrylate (PGMA) via phase inversion method followed by the grafting of natural amino acids through epoxy ring-opening reaction. The grafted PAN membranes possessed highly stable hydrophilic surfaces as a result of the grafting of amino acids, which was adequately demonstrated in attenuated total reflectance–Fourier transform infrared spectroscopy (ATR/FTIR), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. The results of tensile strength and scanning electron microscopy (SEM) images further proved that the surface modification had little effect on their mechanical properties, surface, and cross-sectional morphologies. Meanwhile, remarkable resistance against bovine serum albumin (BSA) and lysozyme (Lyz) fouling was observed for the neutral amino acid-based PAN membranes due to the formation of zwitterionic hydration layer on the membrane surface, while PAN membranes grafted with charged amino acids were able to prohibit the approach of like charged proteins with reduced deposition and provide the driving force for oppositely charged protein adsorption. Furthermore, the ultrafiltration and antifouling performance of PAN membranes were investigated by BSA filtration experiments. Compared with the pristine PAN membrane, all the modified PAN membranes exhibited higher pure water flux, better flux recovery ratio, lower rejection, less total permeation resistance, and preferable stability, having potential applications in protein separation and purification.

Triboelectric nanogenerators (TENGs), which can harvest low-frequency mechanical energy from human activities, are potential for wearable electronics, especially textile-based TENGs. Besides triboelectric performance, wearable comfort, like air permeability, is crucial for wearable electronics. However, the textile-based TENGs integrated with high performance and wearable comfort still remain challenging. Here, we construct the open porous architected PDMS coatings on fabric for breathable fabric-based TENG (oPF-TENG) based on the synergistic effect of insoluble NaCl, DBP and soluble silicone oil. The open porous structure constitutes the airflow channel with the air permeability of ∼73 mm/s. Meanwhile, the porous structure and the PVDF filler enhance the triboelectric output. The open circuit voltage, short circuit current and power density of oPF-TENG reach ∼600 V, ∼15 μA and 5.67 W/m2, respectively. The as-made oPF-TENG with good air permeability and triboelectric output can not only contribute to the human body energy harvesting but also show potential for wearable self-powered sensing.

Accompanying the boom in smart wearable electronics, triboelectric nanogenerators (TENGs) as burgeoning mechanical-to-electrical harvesters have drawn expanding interest. In this study, a kind of novel flexible, high-output TENGs with PAN/FCNT as tribopositive layer and PVDF/PDMS/TiO2as tribonegative layer have been designed and developed. For a synergistic effect, PAN and PVDF possessing strongly polar -CN and -F groups are handpicked as dielectric hosts to ensure maximum charge induction and triboelectrification. Highly conductive FCNT is introduced into the insulated PAN tribopositive layer, serving as the charge transport path to reduce surface charge loss. Additional PDMS is beneficial to strengthen the triboelectronegativity of PVDF tribonegative layer, and engaged as the charge trapping sites to diminish electro-discharge in air. TiO2is employed as filler to build an inorganic-organic (TiO2-PVDF/PDMS) composite dielectric layer because of its triple functions of potent electron capture, high dielectric constant, and promoting the formation of electroactive β-phase PVDF. Meanwhile, the hydrogen bonds between PVDF, TiO2with semi-crosslinked PDMS can stabilize interface and enhance friction output. Consequently, the assembled TENGs exhibit an ultra-high peak-to-peak voltage of 2088 V and a maximum output power of 7.2 W/m2, which shows promising applications in energy supplying and self-powered sensing fields.

MC1Rplays an important role in the regulation of the formation, transfer, and deposition of melanin in animals and is important for determining coat color. Many studies have reported on single nucleotide polymorphisms (SNPs) in the coding sequence of MC1R. However, few studies have investigated the polymorphisms in the 5’-flanking sequence of MC1R. In this study, we sequenced 2000 bp of the 5’-flanking sequence of MC1Rin 300 Taihang chickens with brown feathers (MTH) and 300 Taihang chickens with black feathers (HTH). The sequencing results showed that 4 SNPs (MC1Rg.18838722 G > C, g.18838624 T > C, g.18838694 G > A, and g.18838624 C > T) were located in the 5’-flanking sequence of MC1Rbetween the MTH and HTH groups. Association analysis showed that there was a significant correlation between the 4 SNPs and feather color in Taihang chickens. The correlation between MC1Rg.18838624 T >C and feather color of Taihang chicken was 100%, of which the CC (E1) genotype is MTH and the TT (E2) genotype is HTH. Furthermore, there was a significant correlation between MC1Rg.18838624 T > C and egg production at 302 d. E1 (184.14 ± 0.674) was significantly higher than that in E2 (181.75 ± 0.577) (P< 0.05). Luciferase reporter assays were used to detect the transcriptional activity of MC1R with different SNP genotypes. The results showed that the luciferase activity of E2 was significantly higher than that of E1 (P< 0.05). In addition, transcription factor-binding site predictions showed that E2 creates a new binding site for ZEB1. RT‒qPCR results revealed that the expression of MC1Rin E2 was significantly lower than that in E1 (P< 0.05), and the expression of ZEB1in E2 was significantly higher than that in E1 (P< 0.05). Overexpression and shRNA experiments demonstrated that ZEB1regulates the expression of MC1Rin DF1 cells. ZEB1has a negative regulatory effect on the transcriptional activity of MC1R; it inhibits the expression of MC1Rand affects the feather color of Taihang chickens. This study provides new insight into the molecular mechanism of feather color formation and the transcriptional regulation of MC1Rin Taihang chickens.

The number of egg-laying is an important indicator of reproduction performance in poultry breeding. To investigate the relationship between the function of Angiotensin-converting enzyme (ACE) and egg-laying performance of Taihang chicken, the mRNA and protein expression and single nucleotide polymorphism (SNP) of ACEwere detected. Analysis of ACEbioinformatics and association analysis of polymorphisms were then performed. The polymorphisms analysis of ACEshowed that three SNP loci (g.5066812A>C, g.5080076G>A, and g.5072728A>G) were detected in 800 Taihang chickens with egg-laying records. Association analysis of egg-laying found that ACEg.5066812A>C mutation was significantly associated with the egg-laying performance of Taihang chickens (P< 0.05), and the individuals with the g.5066812A>C mutation showed significantly increasing egg-laying. The mRNA expression was significantly higher in individuals with the AA genotype mutation than those with the AC and CC genotypes (P< 0.01), and the expression of ACE protein levels was consistent with the mRNA expression. Bioinformatics analysis indicated that these mutations affected the secondary and tertiary structure of ACE. This study provides new insights into ACEaffecting chicken egg production and some basis for improving the egg production rate of Taihang chickens.

The economic losses caused by postharvest fruits diseases have attracted global attention. Traditional chemical fungicide could not meet the need of humans. In recent years, microbial agent which has begun to take the place of chemical fungicide comes into people’s vision. The aim of this paper was to investigate the potential of Bacillus amyloliquefaciensstrain BA3 for its biocontrol capability on gray mold decay of pears and its effect on postharvest quality of pears. Compared with other treatments, the inhibition effect on gray mold of washed cell suspension of B. amyloliquefacienswas the best. Consequently it was utilized in subsequent experiments. Spore germination and germ tube length of Botrytis cinereawas 18.72% and 12.85 μm treated with BA3, while the control group was 62.88% and 30.44 μm. We confirmed that increase of the concentration of B. amyloliquefaciens, improved the efficacy of BA3 in controlling gray mold decay of pears. Colonization variation of BA3 in wounds of pears was recorded. To begin with, the populations of B. amyloliquefaciensincreased rapidly and remained stable. On the fourth day, there was a declining trend, after that the population increased to 4 × 105CFU/wound and remained stable. BA3 had no significant effect on mass loss, titratable acidity, firmness and total soluble solids of pears that were stored at 25°C for 7 days comparing with control group. However, the effect of B. amyloliquefacienson ascorbic acid was significantly higher than that of the control group. Our study indicates that B. amyloliquefacienshas a potential as postharvest biocontrol agent on pears.

The economic losses caused by postharvest fruits diseases have attracted global attention. Traditional chemical fungicide could not meet the need of humans. In recent years, microbial agent which has begun to take the place of chemical fungicide comes into people’s vision. The aim of this paper was to investigate the potential of Bacillus amyloliquefaciensstrain BA3 for its biocontrol capability on gray mold decay of pears and its effect on postharvest quality of pears. Compared with other treatments, the inhibition effect on gray mold of washed cell suspension of B. amyloliquefacienswas the best. Consequently it was utilized in subsequent experiments. Spore germination and germ tube length of Botrytis cinereawas 18.72% and 12.85 μm treated with BA3, while the control group was 62.88% and 30.44 μm. We confirmed that increase of the concentration of B. amyloliquefaciens, improved the efficacy of BA3 in controlling gray mold decay of pears. Colonization variation of BA3 in wounds of pears was recorded. To begin with, the populations of B. amyloliquefaciensincreased rapidly and remained stable. On the fourth day, there was a declining trend, after that the population increased to 4 × 105CFU/wound and remained stable. BA3 had no significant effect on mass loss, titratable acidity, firmness and total soluble solids of pears that were stored at 25°C for 7 days comparing with control group. However, the effect of B. amyloliquefacienson ascorbic acid was significantly higher than that of the control group. Our study indicates that B. amyloliquefacienshas a potential as postharvest biocontrol agent on pears.

An active plasmonic device is designed to support multiple perfect absorption peaks using the highly confined graphene surface plasmons excited by silicon-based diffractive gratings. The physical origination corresponding to different absorption peaks is analyzed and the principle of impedance matching is used to explain perfect absorption. We show that the absorption spectrum is effectively controllable over a wide wavelength range by changing the Fermi levels, relaxation time of the graphene and geometric parameters of the device. This study could provide some possibilities facilitating the design of next-generation optical and photoelectronic structures by combining graphene and dielectric grating.

Quasi-2D perovskites, composed of self-organized quantum well structures, are emerging as gain materials for laser applications. Here we investigate the influence of domain distribution on the laser emission of CsPbCl1.5Br1.5-based quasi-2D perovskites. The use of 2,2-diphenylethylammonium bromide (DPEABr) as a ligand enables the formation of quasi-2D film with a large-n-dominated narrow domain distribution. Due to the reduced content of small-ndomains, the incomplete energy transfer from small-nto large-ndomains can be greatly addressed. Moreover, the photoinduced carriers can be concentrated on most of the large-ndomains to reduce the local carrier density, thereby suppressing the Auger recombination. By controlling the domain distribution, we achieve blue amplified spontaneous emission and single-mode vertical-cavity surface-emitting lasing with low thresholds of 6.5 and 9.2 μJ cm–2, respectively. This work provides a guideline to design the domain distribution to realize low-threshold multicolor perovskite lasers.

Inverse wettability gradient movement triggered by water droplets’ surface energy is conductive to many fields, such as droplet transport, water supply and water nanogenerator. Here, a novel phenomenon of spontaneous inverse wettability gradient movement of droplet (i.e., the “swallowing”) is revealed (with an energy transformation ratio at 64.1%) and successfully applied to a new fog-water harvester (i.e., unique gradient wire: UGW). In wetting area on UGW, the largest droplet hanging on more hydrophilic end acts as a gluttonous droplet moving towards inverse wettability to continuously coalesce other droplets and to gain kinetic energy from released surface energy of droplets, resulting in an accelerative reciprocating action like a windshield wiper. As for a given fog flow of 150gs-1m-2, the maximum kinetic energy and velocity of the gluttonous droplet are 1.83 μJ and 3.8cms-1, respectively. This process needs no extra energy consumption and realizes a high water harvest efficiency (1.83μLcm-1s-1). This “Swallowing” action on such UGW allows droplet to accelerate gradually, which is beneficial to power generation from surface energy, heat transfer, and fog-water harvesting, etc.

The excited-state hydrogen and dihydrogen bonding of a dihydrogen-bonded phenol–borane–dimethylamine (BDMA) complex was investigated theoretically by use of time-dependent density functional theory (TDDFT). The coexistence of an intermolecular dihydrogen bond (B–H···H–O) and hydrogen bond (N–H···O) was confirmed by the optimized geometric structure of the dihydrogen-bonded phenol–BDMA complex. The infrared spectra for both the ground and excited states of the dihydrogen-bonded phenol–BDMA complex were also calculated by use of density functional theory (DFT)/TDDFT. As a result, we demonstrated theoretically that the intermolecular dihydrogen bonds B–H···H–O can be significantly strengthened in the excited state. However, the intermolecular hydrogen bond N–H···O in the dihydrogen-bonded phenol–BDMA complex is weakened upon photoexcitation to the S1state. The dynamic changes of the intermolecular dihydrogen and hydrogen bonding are consistent with the calculated bond lengths in different electronic states. The coexistent dihydrogen and hydrogen bonding in the electronic excited states of this dihydrogen-bonded complex was studied theoretically in this work. Furthermore, it was found that the N–H···O hydrogen bond in the cyclic structure of phenol–BDMA complex hindered the dehydrogenation reaction between dihydrogen bonded O–H and B–H1groups, which has been reported for the phenol–borane–trimethylamine complex.

Based on the definition of spectral emissivity, an experimental apparatus for normal spectral emissivity measurement at different temperatures has been developed. The sample and blackbody are heated by the same heating system, which permits to measure spectral emissivity up to 1273K. The temperatures of the sample and blackbody are measured and controlled by an infrared radiation thermometer and PID controller. The signal detection is carried out by a silicon photo detector at 1.5 m. The experimental results focus on the capability of the apparatus to perform emissivity measurements as a function of temperature at a fixed wavelength. Using this apparatus, the spectral emissivity of SUS304 is first measured at different temperatures. In order to validate the measurement capability of the apparatus for different sample, three kinds of steel samples which have different percentages of constituents were measured. The measurement uncertainty of the experimental apparatus is analyzed. The overall uncertainty of the apparatus estimated is about 5%.

AbstractLiu, Y., Zhao, X. Zhang, N., Luo, X. and Tong, Z. 2007. Application of mtDNA sequencing method for individual identification in rustling. J. Appl. Anim. Res., 32: 77–80.The mitochondrial DNA (mtDNA) sequencing has extensive use in human forensics particularly for identification of individuals. In this case report a cattle was being claimed by two owners. Using this technique the disputed cattle was compared with purported mothers, brother, sister and son and the real relatives were identified. However, it has the limitation of being used only in case of different maternal lineages.

Considering the changes of the geometric shielding effect in a molecule as the incident electron energy varing, an empirical fraction, which is dependent on the incident electron energy, is presented. Using this empirical fraction, the total cross sections (TCSs) for electrons scattering from complex polyatomic molecules C2F4 and SO2 are calculated over a wide energy range from 30 to 5000 eV together with the additivity rule model at Hartree-Fock level. In the TCS calculations, the atoms are presented by the spherical complex optical potential, which is composed of static, exchange, polarization and absorption contributions. The quantitative TCSs above 100 eV are in good agreement with those obtained by experiments and other theories. It is proved that the empirical fraction, which exhibits the TCS contributions of shielded atoms in a molecule at different energies, is reasonable.

The luminescent copolymer 2-phenyl-5-[3'-(methacrylamido)phenyl]-1,3,4-oxadiazole and vinylcarbazole (PMAPO–VCZ), combining hole-facilitating moiety, carbazole ring, and electron-facilitating moiety, 1,3,4-oxadiazole, as side groups, was synthesized by a radical polymerization of the olefinic monomer PMAPO and VCZ. For comparison, the homopolymer P-PMAPO was also synthesized by similar procedures. The solubility, thermal, and optical properties of the copolymers were investigated. The synthesized copolymer was soluble in common organic solvents but the homopolymer of PMAPO was dissolved only by hot THF. Thermogravimetric analysis and differential scanning calorimetry measurements showed that the copolymer and homopolymer exhibit good thermal stability up to 360 and 340°C with glass-transition temperatures higher than 105 and 65°C, respectively. The photoluminescence properties were investigated. The results showed that the copolymer emits blue and blue-green light and the emission spectra of monomer and polymers exhibit obvious solvent effect. With the increase of polarity of solvents, the fluorescence spectra distinctly change, appearing with a red shift at room temperature. The concentration-dependent emission spectra change significantly with the increase of concentration. In addition, when N,N-dimethylaniline (DMA) was gradually added to the solution of copolymers, the emission intensity of fluorescence was dramatically increased. However, when the concentration of DMA was increased beyond a certain level, the emission intensity of fluorescence gradually decreased. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2777–2783, 2004

The total (elastic plus inelastic) cross sections for positron scattering from N2 and CO2 over the incident energy range from 30 to 3000eV are calculated using the additivity rule model at Hartree-Fock level. A complex optical model potential modified by incorporating the concept of bonded atom, which takes into account the overlapping effect of electron clouds between two atoms in a molecule, is employed to calculate the total cross section of positron-molecule scattering. The calculated total cross sections are in good agreement with those reported by experiments and other theories over a wide energy range.

The accurate dissociation energy and equilibrium geometry of the b3? state of 7LiH molecule is calculated using a symmetry-adapted-cluster configuration-interaction method in full active space. And the calculated results are 0.2580 eV and 0.1958 nm for the dissociation energy and equilibrium geometry, respectively. The whole potential energy curve for the b3? state is also calculated over the internuclear separation range from about 0.10 to 0.54 nm. The results are fitted by the Murrell-Sorbie function. It is found that the Murrell-Sorbie function form, which is mainly used to fit the ground-state potential energy function, is well suitable for the excited triplet b3? state. The vertical excitation energy from the ground state to the b3? state is calculated to be 4.233 eV. Based on the analytic potential energy function, the harmonic frequency of 610.88 cm^(-1) about this state is firstly estimated. Compared with other theoretical results, this work is the most complete effort to deal with the analytic potential energy function and the harmonic frequency of this state.

A complex optical model potential correlated by the concept of bonded atoms, which considers the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the absolute differential cross sections, the integrated and momentum transfer cross sections for electrons scattered by O2 at intermediate and high energies by using additivity rule model at Hartree-Fock level. In the study, the complex optical model potential is composed of static, exchange, correlation polarization plus absorption contributions. The quantitative absolute differential cross sections, the integrated and momentum transfer cross sections are obtained. Compared with available experimental data, this approach presents good results. It is shown that the additivity rule model together with the complex optical model potential correlated by the concept of bonded atoms is completely suitable for the calculations of the absolute differential cross sections, the integrated and momentum transfer cross sections.

Total cross sections (TCSs) of electrons scattering from triatomic molecules over the energy range from 30 to 5000 eV are investigated employing a new semi-empirical formula. The TCSs of electrons scattering from triatomic molecules SO2, NO2, and CO2 are calculated. The quantitative TCSs are in good agreement with those obtained by experiments. It is shown that the results derived from the semi-empirical formula are much closer to the measurements than other calculations.

A model complex optical potential rewritten by the conception of bonded atom, which considers the overlapping effect of electron cloud, is employed to calculate the total (elastic + inelastic) cross sections with simple molecules (N_(2), O_(2), NO_(2), NO, N_(2)O) consisting of N & O atoms over an incident energy range of 100 - 1600 eV by the use of additivity rule at Roothaan-Hartree-Fock level. In the study, the complex optical potential composed of static, exchange, correlation polarization plus absorption contributions firstly uses bonded-atom conception. The qualitative results are compared with experimental data and other calculations wherever available and good agreement is obtained. The total cross sections of electronmolecule scattering above 100 eV can be successfully calculated.