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Gallium oxide (Ga2O3), with an ultrawide bandgap corresponding to the deep ultraviolet (DUV) range, has attracted significant attention in optical filter‐free photodetectors. In practical terms, DUV photodetectors employed in extreme conditions, for example, flame detection and space exploration, face the challenges of performance degradation caused by high/low‐temperature transformation. Here, DUV photodetectors are tailored with high durability and stability by one‐step‐grown β‐Ga2O3 films via pulsed laser deposition. A high‐oxygen‐pressure scheme effectively addresses the issue of film‐free deposition at specifically high temperatures, facilitating the formation of polycrystalline high‐resistivity β‐Ga2O3 films. As a result, the devices exhibit outstanding performance, including a low dark current (4.4 pA @30 V), high photoresponsivity (147.36 A W−1), and fast response time (3.1/22.6 ms). Additionally, the photoresponse performance shows minimal degradation at high temperatures up to 300 °C and even improves at low temperatures down to −100 °C, ranking it among the most robust DUV photodetectors. The mechanism of photoresponse, involving the exciton formation, bandgap evolution, carrier‐phonon scatter, etc., is also elucidated in a wide temperature range. This work provides an efficient solution for developing robust Ga2O3 DUV photodetectors with excellent performance for extreme‐condition applications. [ABSTRACT FROM AUTHOR]

With the rapid development of modern communication technology, it has become a core problem in the field of communication to find new ways to effectively modulate signals and to classify and recognize the results of automatic modulation. To further improve the communication quality and system processing efficiency, this study combines two different neural network algorithms to optimize the traditional signal automatic modulation classification method. In this paper, the basic technology involved in the communication process, including automatic signal modulation technology and signal classification technology, is discussed. Then, combining parallel convolution and simple cyclic unit network, three different connection paths of automatic signal modulation classification model are constructed. The performance test results show that the classification model can achieve a stable training and verification state when the two networks are connected. After 20 and 29 iterations, the loss values are 0.13 and 0.18, respectively. In addition, when the signal-to-noise ratio (SNR) is 25dB, the classification accuracy of parallel convolutional neural network and simple cyclic unit network model is as high as 0.99. Finally, the classification models of parallel convolutional neural networks and simple cyclic unit networks have stable correct classification probabilities when Doppler shift conditions are introduced as interference in practical application environment. In summary, the neural network fusion classification model designed can significantly improve the shortcomings of traditional automatic modulation classification methods, and further improve the classification accuracy of modulated signals. [ABSTRACT FROM AUTHOR]

The work presented an electrochemical anode method with different electrolyte concentrations and heat posttreatment to control the stoichiometry and structure of Cu2−xS electrocatalysts. X‐ray diffraction, X‐ray photoelectron spectroscopy, and scanning electron microscopy were employed to characterize the composition and morphology, whereas the electrocatalytic activity was evaluated by linear scanning voltammetry and electrochemical impedance spectroscopy. The results showed that the electrochemical method successfully synthesized thin flake‐shaped Cu7S4, which exhibited optimal performance at the electrolyte concentration of 0.45 mol L1 with maximum turnover frequency of 0.786 s−1, maximum mass activity of 0.539 A g−1, minimum charge transfer resistance of 0.156 Ω cm−2, and minimum overpotential of 154 mV at a current density of 10 mA cm−2. In the Cu7S4 structure, Cu2+ and S2− were coordinated in a CuS4 tetrahedral structure, whereas Cu+ and S2− were coordinated in a CuS3 triangular structure. Heat posttreatment could change the stoichiometry from 1.75 to 1.8 and improve the electrochemical performance. In the Cu9S5 structure, the CuS3 triangular structure had disappeared. Under the same conditions, the overvoltage was only 128 mV. [ABSTRACT FROM AUTHOR]

A numerical simulation model of a natural ventilation greenhouse is helpful for improving the production and quality of greenhouse crops in tropical areas. Field experiments show that the mean coefficient of variation of indoor light intensity in four seasons was lower than 10.0%. The highest indoor temperature reached 39.3 °C during summer, while the average indoor temperature ranged from 24 °C to 26 °C in the other three seasons. The average relative humidity in the greenhouse ranged from 76% to 87% annually, which was higher and more stable than that in the external environment. A three-dimensional steady-state numerical model of the greenhouse was established based on computational fluid dynamics. Under natural ventilation conditions, the maximum error between the simulated value and the measured value of the temperature in each measuring point was 5.90%. And the average relative error between the simulated and measured values was 3.0% in the range of 0.7−1.5 m of crop cultivation height. Finally, a numerical simulation of adding side windows and expanding the vents was carried out. The results show that these methods can homogenize the airflow distribution in the greenhouse and improve the utilization efficiency of natural ventilation without more mechanical system operations. [ABSTRACT FROM AUTHOR]

A diamond-like amorphous Fe-Co-PO x catalyst is created through a controllable amorphization engineering. It showcases wonderful OER activity, reaching a potential of 270 mV at 10 mA cm−2, and can operate as an anode stably at 200 mA cm−2 for 300 h with little degradation in overall water splitting. Studies observe that the unique amorphous structure, abundant oxygen vacancies, and the synergistic effect of Fe and Co species are the keys to gain excellent water splitting performance. [Display omitted] • An amorphous FeCo-PO x is constructed by hydrothermal and phosphating treatments. • The catalyst owns a diamond-like morphology and abundant oxygen vacancies. • The catalyst exhibits excellent OER and overall water splitting activity and stability. • The synergy of rich oxygen vacancy and amorphous structure are the key to improve performance. Strategically tuning the composition and structure of transition metal phosphates (TMPs) holds immense promise in the development of efficient oxygen evolution reaction (OER) electrocatalysts. However, the effect of crystalline phase transformation for TMPs on the catalytic OER activity remains relatively uncharted. In this study, we have deftly orchestrated the reaction process of anion-etched precursor to induce the amorphization process of FeCo-PO x from crystalline to amorphous states. The as-obtained amorphous FeCo-PO x (A-FeCo-PO x) exhibited an optimized OER performance with a low overpotential of 270 mV at a current density of 10 mA cm−2, which could be attributed to the flexibility of its amorphous structure and the synergistic effect of oxygen vacancies. Moreover, when incorporated into an overall water splitting (OWS) device configured as A-FeCo-POx(+)||Pt/C(–), it displayed long-term solid stability, sustaining operation for 300 h at a current density of 200 mA cm−2. This work not only provides valuable insights into understanding the transformation from crystalline to amorphous states, but also establishes the groundwork for the practical utilization of amorphous nanomaterials in the field of water splitting. [ABSTRACT FROM AUTHOR]

Huntington's disease (HD) is a progressive genetic neurodegenerative disease caused by an abnormal expansion of a cytosine-adenine-guanine trinucleotide repeat in the huntingtin gene. One pathological feature of HD is neuronal loss in the striatum. Despite many efforts, mechanisms underlying neuronal loss in HD striatum remain elusive. It was suggested that the mutant huntingtin protein interacts mitochondrial proteins and causes mitochondrial dysfunction in striatal neurons. However, whether axonal transport of mitochondria is altered in HD striatal neurons remains controversial. Here, we examined axonal transport of single mitochondria labelled with Mito-DsRed2 in cultured striatal neurons of zQ175 knock-in mice (a knock-in mouse model of HD). We observed decreased anterograde axonal transport of proximal mitochondria in HD striatal neurons compared with wild-type (WT) striatal neurons. Decreased anterograde transport in HD striatal neurons was prevented by overexpressing mitochondrial Rho GTPase 1 (Miro1). Our results offer a new insight into mechanisms underlying neuronal loss in the striatum in HD. • Cultured striatal neurons were mainly MSNs that are the most vulnerable neurons in HD. • Anterograde axonal transport of proximal mitochondria was altered in HD striatal neurons. • Overexpressing Miro1 prevented altered mitochondrial transport in HD striatal neurons. [ABSTRACT FROM AUTHOR]

A six-week feeding trial was carried out to evaluate the effects of different dietary Myo -inositol (MI) levels on growth, feed efficiency, immunity, and antioxidant properties of juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂) fed low-fishmeal diets. Seven experimental diets were made to contain 50, 100, 169, 241, 309, 386, and 459 mg/kg of MI (analyzed values, dry matter basis), being abbreviated as MI-50, MI-100, MI-169, MI-241, MI-309, MI-386, and MI-459, and each MI treatment had three replicates. Twelve fish (average initial body weight: 18.7 ± 0.1 g) were allocated to each replicate, being hand-fed their diets to apparent satiation on 8:00 am and 16:30 pm. The results indicated that within the range of 50–241 mg/kg dietary inositol, weight gain percentage (WG%), feed efficiency (FE) and protein efficiency ratio (PER) were increased with the increasing of MI, and above the 241 mg/kg, they were dropped, especially at 386 and 459 mg/kg. According to the broken-line regression analysis conducted to assess the relationship between WG% and dietary MI levels, the optimum MI dose was 267.9 mg/kg (dry weight) in the low-fishmeal diet of hybrid grouper. Condition factor (CF), viscerosomatic index (VSI), hepatosomatic index (HSI), and intestinal index (ISI) were significantly (P < 0.05) affected by dietary MI levels, varying with a similar trend as WG%. Fish fed MI-241 had the highest values of serum lysozyme (LZM), hepatic total antioxidant capacity (T-AOC) as well as the relative mRNA level of hepatic insulin-like growth factor-Ⅰ (IGF-Ⅰ) among all treatments. In conclusion, optimum dietary MI requirement for the maximal growth of hybrid grouper was 267.9 mg/kg, and suitable dietary MI supplementations improve growth, immunity, and antioxidant properties of juvenile hybrid grouper fed low-fishmeal diets. • An optimal MI content of 267.9 mg/kg is recommended in the low-fishmeal diets of hybrid grouper. • Suitable MI supplementations improve growth, immunity and antioxidant properties of fish. • Dietary MI levels exceeded 368 mg/kg have a negative impact on fish. [ABSTRACT FROM AUTHOR]