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Dual-band photodetectors (PDs), which can sense two specific bands simultaneously or alternately, have great applications in spectral analysis, imaging, optical communication, and so on. However, some studies on dual-band PDs are mostly limited by drawbacks such as high cost, fixed dual-band range, and lattice mismatches between interfaces. Herein, we propose organic–inorganic halide perovskite single crystal heterojunctions (PSCHs) for dual-band detection via solution-processed epitaxial growth, with a structure of bismuth doped MAPbCl3/intrinsic MAPbBrxCl3−x/bismuth doped MAPbIyBr3−y/intrinsic MAPbIzBr3−z (where x, y, and z are between 0 and 1). The peak position and the full-width at half maximum (FWHM) value of dual-band PDs can be adjusted by changing the proportion of halide in the perovskite single crystal layers in the device, achieving different dual-band spectral response ranges. Eventually, a device exhibits two farthest peaks at 465 nm and 820 nm of visible (Vis)/near-infrared (NIR) range with the corresponding FWHM values of 22.6 nm and 19.4 nm under 2 V. The PSCH-based device can be called dual narrowband PD exhibiting good stability and a response speed of hundreds of microseconds, attributed to the small lattice mismatch and heterostructure. It also shows a high spectral rejection ratio (∼360). In conclusion, this article proposes an approach for customizing dual narrowband PDs with tunable spectral response ranges based on solution-processed epitaxial growth. [ABSTRACT FROM AUTHOR]

Introduction: We report a case of B-cell acute lymphoblastic leukemia (B-ALL) involving the breakpoint cluster region (BCR) and platelet-derived growth factor receptor alpha (PDGFRA) (BCR::PDGFRA) fusion gene, classified as a BCR::ABL1-like subtype. To our knowledge, this is the first such report. Case Presentation: The patient tested negative for BCR::ABL1 fusion. t(4;22)(q12;q11.2) was detected by karyotype analysis. BCR::PDGFRA transcripts were detected by RNA sequencing. Dasatinib combined with chemotherapy was ineffective. Furthermore, EZH2 mutation was detected. Imatinib, which led to complete remission, was administered; flow cytometry revealed that the minimal residual disease had dropped to 0.008%, and RT-qPCR revealed that BCR::PDGFRA/ABL1 dropped to 9.18 × 10−4. Conclusion: It is noteworthy that imatinib was more effective than dasatinib in our case, although the duration of remission was short. Our findings suggest that other therapies like allogeneic hematopoietic stem cell transplantation may need to be combined to improve long-term survival in ALL cases with BCR::PDGFRA. [ABSTRACT FROM AUTHOR]

An energy-saving control strategy for wheel loaders is proposed in this paper to address the issue of high energy consumption during their operation. The strategy is based on the intelligent identification of working stages, allowing for staged power matching and resulting in reduced energy consumption. Each work stage of the loader is identified by matching it to the main pump pressure waveform and actuator pilot pressure waveform. Using a sliding time window method, pressure waveforms from each working stage are subjected to feature extraction. A bidirectional long short-term memory neural network (BILSTM) algorithm is then used to establish an intelligent recognition model. Based on work stage identification, an energy-saving control strategy based on power matching is proposed for the shoveling stage of the loader, and the Grey Wolf optimization (GWO)-PID algorithm is utilized for control parameter tuning. Finally, the effectiveness of the energy-saving control strategy based on work stage identification is verified through experiments. The research results indicate that the BILSTM recognition model outperforms other models with a recognition accuracy of 96.1%. The optimal time window width is 0.6 s, and the proposed energy-saving control strategy achieves a fuel-saving rate of 6.81%. This method provides feasibility for reducing energy consumption in construction machinery and achieving energy-saving and carbon-reduction goals. [ABSTRACT FROM AUTHOR]

The perovskite single crystals (PSC) produced by solution‐processed metallic ions doping have a thick p–n junction (greater than 10 µm). Meanwhile, to achieve high responsivity, the carrier drift length (µτE) has to be larger than the dimensions of the detector. If the p–n junction is quite thick, a high bias voltage is required. For the practical application of photodiode, it is imperative to find a means to generate a thin p–n junction. A productive technique is suggested for forming a thin p–n junction by diffusing metallic ions, resulting in a longer drift length of the carrier than the depletion width. Thinner p–n junction leads to reduced dark current density (0.5 µA cm−2), low trap density (5.71 × 108 cm−3), high mobility (417 cm2 V−1 s−1), and hence increased responsivity (77.69 A W−1) for 30 µW cm−2 UV illumination under a low applied voltage of −15 V. A quick response time with a rise/fall duration of 22 ms/30 ms under 0 V and long‐term stability for over 3 months in ambient airis achieved. To comprehend the performance with the thinner p–n junction‐based photodiodes, the results under UV–Vis illumination are examined and compared. The outcomes hint at a method that holds promise for producing efficient photodiodes. [ABSTRACT FROM AUTHOR]

Mechanical energy harvesters fabricated with halide perovskites display excellent electrical output because of their prominent permittivity. An all-inorganic lead-free double perovskite, Cs2AgBiBr6 (CABB), with competitive performance, excellent environmental stability and non-toxicity can break the confines of practical unavailability. CABB microcrystals, which are effective nucleating agents and dielectric fillers, are embedded into a polyvinylidene-fluoride (PVDF)-matrix as efficient electron-acceptors to induce electro-active PVDF β-phase formation and enhance the composite dielectric constant, which contributes to notable hybrid electric outputs. CABB–PVDF hybrid nanogenerators with the optimal CABB concentration of 20 wt% possess triboelectric and piezoelectric effects, with a nanogenerator with a 1.2 cm × 1.2 cm effective contact area and 70 μm film thickness exhibiting a unique response with an open-circuit voltage of 126 V and a short-current density of 4.67 mA m−2 under a 0.5 Hz mechanical frequency and 4 cm s−1 motion speed. An identical device achieves the highest output power density of 0.39 W m−2 at 8 Hz and 0.64 m s−1, which could light up at least 86 commercial LEDs using a 1 μF capacitor and power small electronic devices such as a timer using 22 μF. The corresponding force sensing is achieved with a different distribution of external forces using a 10 wt% CABB–PVDF composite film. This functional composite maintains its stability and charge retention capacity for effective application in various environmental conditions. [ABSTRACT FROM AUTHOR]

This study presents an error flow research method for simulation models of hydraulic systems in construction machinery based on the state-space approach, aiming to ensure the reliable application of digital twin models. Initially, a comprehensive analysis of errors in the simulation modeling of hydraulic systems in construction machinery was conducted, highlighting simulation model parameters as the primary error sources. Subsequently, a set of metrics for assessing the accuracy of simulation models was developed. Following this, an error flow analysis method for simulation models of hydraulic systems in construction machinery was explored based on the state space approach, delving into the sources, transmission, and accumulation of errors in the simulation modeling of valve-controlled cylinder systems. The research results unequivocally indicate that the spring stiffness, viscous damping coefficient, and hydraulic cylinder external leakage coefficient are critical parameters affecting the accuracy of valve-controlled cylinder system simulation models. Furthermore, it was observed that the simulation model of the control valve has a significantly greater impact on the errors in the valve-controlled cylinder system simulation model than the hydraulic cylinder model. In conclusion, the reliability of the error flow model was confirmed through simulation experiments, revealing a maximum relative error of only 3.73% between the error flow model and the results of the simulation experiments. [ABSTRACT FROM AUTHOR]

Perovskite single crystals (PSCs) photodiodes with p–n junctions have been widely studied due to their effective blocking of injected current with barriers and quickly separating the electrons and hole pairs with a built-in electric field. Here, we report a solution-processed epitaxial (SPE) growth method to fabricate p–n photodiodes based on MAPbBr3 PSCs. In the structure of the MAPbBr3 PSCs, bismuth donor doping will change the conduction type from p-type to n-type and redshift the absorption edge along with the increase in Bi concentration. Therefore, this work successfully fabricates the p–n photodiodes with homo-epitaxial Bi-doped (n-type) MAPbBr3 layers grown on the surface of undoped (p-type) MAPbBr3 PSCs substrates through the SPE growth method. The p–n photodiodes achieve a tunable spectral response by simply adjusting the Bi doping concentrations of homo-epitaxial MAPbBr3 layers. The spectral response peaks redshift from 559 to 601 nm, with an increasing Bi doping level of 0% to 15%. [ABSTRACT FROM AUTHOR]

Low‐cost and efficient large‐scale triboelectric nanogenerator (TENG) is considered as the new scheme for distributed mechanical conversion or renewable energy utilization. An extremely popular all‐inorganic lead‐free double perovskite Cs2AgBiBr6 (CABB) has emerged as extraordinary potential material in triboelectric semiconductors' substitution, overcoming high‐impedance limitations associated with organic‐polymer‐insulator based materials. In this study, assembled by the certified available positive frictional material CABB, TENG with sandwiched structure of ITO/compact‐TiO2/mesoporous‐TiO2/CABB – the poly‐tetra‐fluoroethylene/Al exhibits appropriate performance on environmental stability and output capacity for which structure can impede charges decay. Fabrication process comparison shows that as an inexpensive large‐scale functional films preparation method, sprayed CABB TENG with brilliant relative dielectric constant and work function difference possess more distinguished output characteristics. This is confirmed by higher open‐circuit voltage of 105 V, larger short‐current density of 2.45 mA m−2 at 0.25 Hz motion parameter, and more abundant output power density of 0.76 W m−2 under 10 Hz. Further study confirms that both higher frequency and larger contact‐area are conducive to total output power, while terminal charging speed is inversely or positively proportional with capacitance or mechanical frequency. Final physical display effect of sprayed CABB TENG lights up at least 53 commercial yellow‐LEDs, holding decent energy conversion ability. [ABSTRACT FROM AUTHOR]

Single-crystalline perovskites with low trap density, high mobility, and long diffusion length are ideal for creating high-performance optoelectronic devices. However, growing mixed-halide single-crystalline perovskite films or wafers with arbitrary halide components and controlled thickness is challenging. Here, a liquid-phase epitaxial (LPE) method based on inverse temperature crystallization (ITC) was developed to address this issue, using orientated MAPbCl3 single crystals as substrates, resulting in a series of single-crystalline MAPbBrxCl3−x perovskite films with continuous variable bandgaps from 2.19 eV to 2.91 eV and excellent optical-electrical properties. A series of planar-type photodetectors are designed and fabricated based on the epitaxial single-crystalline MAPbBrxCl3−x films, which present a dual-mode detection ability with response in both broadband and narrowband spectra ranges by manipulating the light incident direction from top illumination and bottom illumination, respectively. Through adjusting halide compositions, these photodetectors exhibit a selective optimal response spectrum and excellent optoelectronic detection performance, demonstrating the potential for multi-functional spectral detection with epitaxial perovskite devices. [ABSTRACT FROM AUTHOR]

Compared with the pure lead-based MAPbBr3 (MA = CH3NH3) perovskite single crystals (PSCs), tin–lead alloy (MAPbxSn1−xBr3) PSCs with higher carrier mobility and longer carrier lifetime are expected to perform as better-quality ionization radiation detectors. In this work, we design MAPbBr3–MAPb0.9Sn0.1Br3–MAPb0.8Sn0.2Br3 structure detectors by employing solution-process epitaxial growth. Because of the gradient change in tin element proportion, the relatively low mismatch rates between different PSC layers can effectively reduce defects generated at the interface, which improves charge collection efficiency. Moreover, band barriers between different PSC layers form depletion layers due to the differences in band structure, and the high resistivity and built-in electric field of depletion layers can suppress dark current under high voltages. The optimized detector exhibits a high x-ray detection sensitivity of 6.76 × 104μC Gy−1 cm−2 and the lowest detectable dose rate of 7.4 nGy s−1 under 40 kVp x-ray radiation. Based on 241Am (5.95 MeV) α particle irradiation, tin–lead HD has lower detection noise and more obvious response compared to MAPbBr3 PSCs. The electron mobility was indicated as high as 612 cm2 s−1 V−1, and the mobility-lifetime (μτ) products were measured to be 3.5 × 10−3 cm2 V−1 using the Hecht equation, demonstrating superior transport properties. [ABSTRACT FROM AUTHOR]

With the deepening of the global division of labor, it is of great practical significance to study the impact of agricultural global value chain (GVC) on the ecological footprint. Based on the data of trade in value added provided by the OECD, this study adopts the dynamic panel model and moderating effect model to systematically examine the impact of agricultural GVC on ecological footprint and the moderating effect of environmental regulation. Empirical results show that upgrading the position of agricultural GVC significantly reduces the ecological footprint. Further, the effect of agricultural GVC on ecological footprint is more pronounced in middle‐ and low‐income countries than in high‐income countries. The mechanism test using the moderating effect model proves that there is a positive moderating effect of environmental regulation on the relationship between agricultural GVC and ecological footprint. The findings disclose the environmental effect behind upgrading the position of agricultural GVC and offer certain enlightenment from the perspective of environmental regulation for a country to participate in the agricultural GVC, alleviate the pressure on the ecological footprint and ultimately achieve sustainable development. [ABSTRACT FROM AUTHOR]

High-sensitivity, large-scale, and low-cost flexible X-ray detectors are useful in many applications, such as medical and nondestructive imaging. MAPbX3 (MA = CH3NH3; X = Cl, Br, and I) are promising materials because of their extraordinary optoelectronic properties and simple processing methods. Herein, we propose a novel perovskite-based p–n homojunction for large-scale and high-sensitivity flexible X-ray detectors, whose potential barrier can block electron injection transport, affording a low dark current. Incorporating Bi3+ in MAPbI3 induces n-type doping without introducing lattice mismatch, minimizing photogenerated carrier losses. The doping concentration of the n-type layer was controlled to find a compromise between photo and dark currents of the X-ray detector, realizing a device with a high sensitivity of 1969.75 μC Gy−1 cm−2 and a low detection limit of 147 nGy s−1. The fabrication process and storage were realized under ambient conditions, and no performance degradation was observed after our device was stored for one month under ambient conditions with 30–50% humidity. Finally, a 100 cm2 flexible X-ray detector was fabricated to verify its ability for large-scale X-ray imaging. This study provides new insight into reducing noise in large-scale and flexible perovskite-based devices. [ABSTRACT FROM AUTHOR]

Narrowband photodetectors have broad application prospects in many fields where only a range of specific wavelengths of light needs to be detected. However, the current narrowband detectors have some disadvantages, such as the integration is difficult, the full width at half-maximum is not narrow enough, and the spectral rejection ratio is not ideal (≤20). Here, we present a self-filtering photodetector based on MAPbX3 single crystals with a very narrow spectral response and a full width of 15 nm at half maximum. It also shows a high responsivity (∼100 mA/W) and a high spectral rejection ratio (∼300). What is more, the response spectrum can be tuned within a certain range (from 440 to 560 nm) by varying the halide composition and thus its bandgap. This provides a new design paradigm for self-filtering narrowband photodetectors. [ABSTRACT FROM AUTHOR]

Due to the importance of product and geographical diversification of exports, the gravity equation was used to predict export diversification for 19 Asian countries from 2004 to 2017 and the System Generalised Method of Moments was used to analyse the dynamic impact of globalisation at the disaggregated level of the diversification of sectoral exports and the goods specialisation on income inequalities. The results show that sectoral diversification of exports is the driving force of inequality. Furthermore, increased diversification of exports in the highly-income countries of Asia increases inequality and has little impact on low-income countries in Asia. [ABSTRACT FROM AUTHOR]

Narrowband photodetection provides important information in a specific wavelength range. Specially, the use of nonoptical‐filter narrowband photodetectors based on MAPbX3 (MA = CH3NH3; X = Cl, Br, I) perovskites is reported of great potential. However, current MAPbX3‐based narrowband photodetectors have to sacrifice their photocurrent and response speed to achieve an acceptable spectral rejection ratio. In this work, a new type of heterojunction photodetector (hetero‐PD) with a structure of (n‐type doped MAPbCl3)/(intrinsic MAPbBr2.5Cl0.5)/(n‐type doped MAPbBr3) via epitaxial growth is demonstrated as a narrowband photodetector. Through optical bandgap engineering, photons with different wavelength can be absorbed in different layers. Owing to the n–i–n energy band structure, most external bias would apply on a tiny region near the n–i heterojunction. Besides, the energy barriers in the heterojunctions can block holes from injection and collection, resulting in low‐noise electron‐only hetero‐PDs. By sufficiently suppressing the background noise from short‐wavelength photons, hetero‐PDs are capable of achieving a high spectral rejection ratio of 98.1% under an electrical field of 8 V cm−1. Moreover, hetero‐PDs exhibit a high external quantum efficiency value of 45%, a narrow full width at half‐maximum of 13 nm, and a response time of 1.35 µs. [ABSTRACT FROM AUTHOR]

All-inorganic halide semiconductors with perovskite or perovskite-like structure have aroused a widespread concern recently for its environmental friendliness and stabilities while possessing excellent optoelectronic properties. Double perovskite Cs2AgBiBr6 single crystal (SC) is one of the most representative materials in the latest research area. To further improve the device response range and decrease its dark current density effectively, functional layers based on the solution-processed epitaxial method are normally fabricated as heterojunctions. Herein, a novel idea of a broadband heterojunction MAPbI3 (MA = CH3NH3)/Cs2AgBiBr6 is proposed in this work to achieve this goal. A MAPbI3 layer is fabricated on Cs2AgBiBr6 SC substrates through immersing Cs2AgBiBr6 SC into MAPbI3 solution at a MAPbI3 crystallization temperature. Ultimately, this heterojunction device expands the absorption limit from 618 to 838 nm, makes responsivity range redshift from 629 to 860 nm, and achieves a responsivity of 16.8 mA W−1 while the detectivity of 1.33 × 1011 Jones under 622 nm 0.55 mW cm−2 illumination at −20 V bias, maintaining excellent optoelectronic properties. [ABSTRACT FROM AUTHOR]

The ever-growing threats of bacterial infection and chronic wound healing have provoked an urgent need for novel antibacterial wound dressings. In this study, we developed a wound dressing for the treatment of infected wounds, which can reduce the inflammatory period (through the use of gentamycin sulfate (GS)) and enhance the granulation stage (through the addition of platelet-rich plasma (PRP)). Herein, the sustained antimicrobial CMC/GMs@GS/PRP wound dressings were developed by using gelatin microspheres (GMs) loading GS and PRP, covalent bonding to carboxymethyl chitosan (CMC). The prepared dressings exhibited high water uptake capability, appropriate porosity, excellent mechanical properties, sustain release of PRP and GS. Meanwhile, the wound dressing showed good biocompatibility and excellent antibacterial ability against Gram-negative and Gram-positive bacteria. Moreover, in vivo experiments further demonstrated that the prepared dressings could accelerate the healing process of E. coli and S. aureus -infected full-thickness wounds i n vivo, reepithelialization, collagen deposition and angiogenesis. In addition, the treatment of CMC/GMs@GS/PRP wound dressing could reduce bacterial count, inhibit pro-inflammatory factors (TNF-α, IL-1β and IL-6), and enhance anti-inflammatory factors (TGF-β1). The findings of this study suggested that biocompatible wound dressings with dual release of GS and PRP have great potential in the treatment of chronic and infected wounds. [ABSTRACT FROM AUTHOR]

Perovskite single crystals (PSCs) can be used to fabricate high performance photoelectric detectors due to their superior optoelectronic characteristics. Generally, an external electric field needs to be applied in PSC-based detectors to improve their charge collection efficiency. However, the large external electric field increases the dark current, which will enlarge the noise current. To alleviate this drawback, an approach of fabricating a PSC-based heterojunction is proposed in this work, which contributes to reduced dark current in a relatively high reverse electric field. In this study, a heterojunction formed by epitaxially growing MAPbBr3 PSCs on Bi3+-doped MAPbCl3 PSCs is reported, and it shows relatively low trap density and higher built-in potential. The as-fabricated Au-MAPbBr3/Bi3+-doped MAPbCl3 PSC heterojunction-Au photodiode shows smaller dark current density, better long-term current stability and reduced noise level by approximately four orders compared to the Au–MAPbBr3 PSCs–Au photoconductor device under an external reverse voltage of 100 V (mean electric field of ∼31.5 V mm−1). Moreover, the pN heterojunction photodiode shows favorable X-ray detection performance, with a fast response time of 4.89 μs and high sensitivity of 1.72 × 103 μC Gyair−1 cm−2 for 50 kVp X-ray photons under a reverse electric field of 31.5 V mm−1. This work confirms that the epitaxial fabrication of PSC heterojunctions may be a promising strategy to enhance the performance of X-ray photodetectors. [ABSTRACT FROM AUTHOR]

The ion migrations in lead halide perovskite (LHP)‐based devices are complex processes due to the generation of charges and migration multipaths. The migrating ions are generated mainly from element defects and dislocation defects, and transport along paths of element vacancies and grain boundaries. In this regard, it is of interest to investigate the different influences of the two defect types and paths. Herein, the current–voltage hysteresis and X‐ray photoelectron spectra of almost‐dislocation‐free LHP single crystals (LHPSCs) with different halide components are investigated. The ions cannot migrate in iodine‐based LHPSCs. A decrease in halide vacancy content in a bromine–chlorine‐based perovskite single crystal can effectively limit the ion migration. This study provides useful insights to understand the different dominant factors determining the ion migration in LHPs. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to estimate forced vital capacity (FVC) by analyzing incomplete forced expiratory flow–time (FEFT) curves using the new Luus–Jaakola (NLJ) optimization procedure. Methods: Complete FEFT curves from 90 subjects with and without respiratory disease were used to validate the method, and its application performance was evaluated by FEFT curves containing incomplete curves from nine obstructive patients. First, a lumped parameter model of the FEFT curve, taking FVC as one of the model parameters, is chosen. The 0–1 s, 0–1.5 s, …, 0–6 s curves chosen from the accepted FEFT curves are, respectively, taken as the local system observations. Then, the NLJ optimization procedure was used to get the estimate of FVC (FVCest) by estimating the model parameters. Finally, FVCest was compared with the measured FVC (FVCmea). Results: The difference between FVCest and FVCmea decreased with the lengths of observed curves increasing. When the lengths of observed curves reached 3 s, the mean difference (±SD) between FVCest and FVCmea was −11 ± 58 mL. Estimated FVC derived from the incomplete curves were close to FVC from accepted maneuvers. Conclusion: The method can be used to estimate FVC by analyzing an incomplete FEFT curve, providing the length of the curve is more than 3 s. Significance: This method can help the subjects who cannot complete the forced expiratory maneuver to provide a reliable estimate of FVC and also can be used to analyze the unacceptable spirometry because of early termination of exhalation. [ABSTRACT FROM AUTHOR]

Under the background of dealing with global warming, the widespread use of the internet provides a new idea for countries to develop a low-carbon economy at the right time. Based on the panel data of 70 countries from 1995–2018, this paper empirically analyzes the relationship between internet usage, human capital, and CO2 emissions under different levels of economic development by using system GMM and a threshold regression model. The results show that internet usage and human capital are essential drivers of low-carbon economy development, and human capital can inversely regulate the impact of internet usage on CO2 emissions. Internet usage can increase CO2 emissions when human capital is below the threshold value, and it can significantly inhibit CO2 emissions when human capital exceeds the threshold value. In other words, with the accumulation of human capital, the effect of internet usage on CO2 emissions has an inverted U-shaped nonlinear relationship. Furthermore, the empirical analysis of high-income and middle- and low-income countries indicates the hindrance effect of internet usage on CO2 emissions is more evident in high-income countries. For both the high-income and middle- and low-income countries, the relationship between internet usage and CO2 emissions generally shows an inverted "U-shaped" relationship, first rising and then falling as human capital accumulates. [ABSTRACT FROM AUTHOR]