LINKED CONTENT
This article is linked to McCurdy et al and McCurdy papers. To view these articles, visit https://doi.org/10.1111/apt.15286 and https://doi.org/10.1111/apt.15457.
Although arthropods are important viral vectors, the biodiversity of arthropod viruses, as well as the role that arthropods have played in viral origins and evolution, is unclear. Through RNA ...sequencing of 70 arthropod species we discovered 112 novel viruses that appear to be ancestral to much of the documented genetic diversity of negative-sense RNA viruses, a number of which are also present as endogenous genomic copies. With this greatly enriched diversity we revealed that arthropods contain viruses that fall basal to major virus groups, including the vertebrate-specific arenaviruses, filoviruses, hantaviruses, influenza viruses, lyssaviruses, and paramyxoviruses. We similarly documented a remarkable diversity of genome structures in arthropod viruses, including a putative circular form, that sheds new light on the evolution of genome organization. Hence, arthropods are a major reservoir of viral genetic diversity and have likely been central to viral evolution.
The ubiquity of microplastics in the world's ocean has aroused great concern. However, the ecological effects of microplastics at environmentally realistic concentrations are unclear. Here we showed ...that exposure of marine medaka (Oryzias melastigma) to environmentally relevant concentrations of 10 μm polystyrene microplastics for 60 days not only led to microplastic accumulation in the gill, intestine, and liver, but also caused oxidative stress and histological changes. Moreover, 2, 20, and 200 μg/L microplastics delayed gonad maturation and decreased the fecundity of female fish. Alterations of the hypothalamus-pituitary-gonadal (HPG) axis were investigated to reveal the underlying mechanisms, and gene transcription analysis showed that microplastic exposure had significantly negative regulatory effects in female HPG axis. Transcription of genes involved in the steroidogenesis pathway in females were also downregulated. This disruption resulted in decreased concentrations of 17β-estradiol (E2) and testosterone (T) in female plasma. Furthermore, parental exposure to 20 μg/L microplastics postponed the incubation time and decreased the hatching rate, heart rate, and body length of the offspring. Overall, the present study demonstrated for the first time that environmentally relevant concentrations of microplastics had adverse effects on the reproduction of marine medaka and might pose a potential threat to marine fish populations.
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•The effects of microplastics at environmentally realistic levels were investigated.•Microplastics accumulated in the gill, intestine, and liver of marine medaka.•Microplastics caused oxidative stress and structural damages in these tissues.•Microplastics exhibited reproductive endocrine disruption in a sex-dependent manner.•Prenatal exposure to microplastics affected the early development of offspring.
The oxygen reduction reaction (ORR) plays a key role in many efficient and clean energy systems, specifically in fuel cells and metal-air batteries. As a widely used commercial ORR catalyst, Pt/C has ...the limitations of high price and scarce reserves. Metal-nitrogen-carbon (M-N-C) is considered as one of the most promising alternatives to replace noble metal catalysts. However, how to balance the high catalytic activity and stability is still a major challenge. In this study, we report a novel non-noble metal composited catalyst, Fe-N-C@Ti
3
C
2
T
x
, synthesized by a facile separated pyrolysis strategy. The Fe-doped Zeolitic Imidazolate Framework-8 (ZIF-8) was converted to Fe-N-C by carbonization firstly, which was then mixed with few-layered Ti
3
C
2
T
x
and pyrolyzed together to obtain Fe-N-C@Ti
3
C
2
T
x
composites. This separated pyrolysis strategy can not only ensure the high carbonization temperature required by Fe-N-C for high catalytic activity but also avoid the damage of MXene caused by high pyrolysis temperature. Thus, Fe-N-C@Ti
3
C
2
T
x
exhibited excellent ORR activity and stability in alkaline solution, including a half-wave potential of 0.887 V
vs.
RHE, limiting diffusion current density of 6.3 mA cm
−2
, and even no attenuation after 10 000 cycles in 0.1 M KOH. Meanwhile, it also exhibited surprisingly good performance in acidic solution, with a half-wave potential of 0.777 V
vs.
RHE, limiting diffusion current density of 5.7 mA cm
−2
, and only 11 mV attenuation after 10 000 cycles in 0.1 M HClO
4
. The superior ORR performance of the synthesized Fe-N-C@Ti
3
C
2
T
x
could be attributed to the strong coupling effect between Fe-N-C and MXene, the reduced intrinsic and charge transfer impedance, and the increased electrochemically active surface area. This work here provides a new strategy for the development of M-N-C based non-noble metal-based catalysts with high activity and stability, and a promising future for applications in fuel cells and metal-air batteries.
The facilely synthesized Fe-N-C@Ti
3
C
2
T
x
composite exhibited excellent ORR activity and extraordinary stability in both alkaline and acidic solutions.
As a natural refrigerant, carbon dioxide is safe, economic and environmentally sustainable which can be used in heat pump and refrigeration systems especially in transcritical cycles. From the early ...1990s, in which the carbon dioxide transcritical cycle began, theoretical and experimental researches, as well as commercial system development, has improved to make the transcritical system performance to a level similar to that of conventional heat pump systems. This paper presents an overview of transcritical carbon dioxide heat pump and refrigeration systems. The paper introduces a summary of the history and main application of carbon dioxide's use as a refrigerant firstly. Secondly, the properties of supercritical pure carbon dioxide and that containing polyalkylene glycol (PAG) lubricants are analyzed and reviewed. In Section 3 the paper began with an analysis of some special characteristics of the basic carbon dioxide transcritical cycle such as the optimum system high pressure and so on, and then followed by a performance analysis and comparison of several novel transcritical cycles. The study finally presents a review of research on transcritical carbon dioxide heat pump systems, which covers the main components and research hotspots, such as heat transfer and expander.
•A full-scale overview of transcritical carbon dioxide heat pump and refrigeration systems.•The latest researches on transcritical carbon dioxide heat pump and refrigeration systems.•Our latest researches on transcritical carbon dioxide expander.
•NH3/Diesel dual direct injection strategies were investigated on a two-stroke engine.•The combustion modes and phase of liquid phase ammonia spray was regulated by JCCI.•Ammonia combustion duration ...was shortened by dual-direct injection strategy.•The mode of dual fuel could achieve higher ITE than that of the pure diesel mode.•Soot, CO and thermal type NOx were suppressed effectively under the dual fuel mode.
Ammonia has been attracting widely interests among the world because of the property of carbon-free energy resource. As the alternative and renewable fuel of internal combustion engine, its application is expected to comply with the GHG (greenhouse gas) reducing goal of traditional power equipment. However, the defects of low combustion efficiency, high pollutant emissions and poor power performance are restricting the promotion of ammonia fuel. Experimental validation and evaluation of Ammonia/Diesel dual direct injection mode of two-stroke low speed engine were conducted in the current study based on the concept of diesel Jet Controlled Compression Ignition (JCCI). The engine performance and emission characteristics were discussed under the cases of various ammonia injection quantity, timing and different diesel injection timing conditions. It reveals that the injection timing of diesel, which is responsible for the ignition of liquid phase ammonia spray, can regulate the engine combustion phase precisely. The combustion duration of ammonia is accelerated by the ignition of high energy diesel flame, which results in the improvement of indicated thermal efficiency (ITE). Moreover, the worrying fuel type NOx emission, which is mainly produced by the ammonia combustion, is reduced by the reasonable arrangement of injection timings of diesel and ammonia.
Linked ContentThis article is linked to Ludvigsson et al and Ludvigsson and Emilsson papers. To view these articles visit https://doi.org/10.1111/apt.14991 and https://doi.org/10.1111/apt.15055.
A model-free predictive current control (PCC) of interior permanent-magnet synchronous motor (IPMSM) drive systems based on a current difference detection technique is proposed. The model-based PCC ...(MBPCC) of IPMSM requires knowledge of parameters such as resistance, q-axis inductance, and extended back EMF. This paper develops a new model-free approach that alleviates the need for excessive prior knowledge about the system and only utilizes the stator currents as well as the current differences corresponding to different switching states of the inverter. Despite the salient difference of the proposed approach, it adopts a measure similar to that in the MBPCC approach to obtain the next switching state of the inverter by minimizing a cost function. It is noteworthy that the proposed method is easy to implement due to its simplicity and free of any multiplication operation. For comparison purposes, a digital signal processor, TMS320LF2407, is used to execute the two aforementioned current control techniques. Several experimental results show that the proposed method can significantly improve the current-tracking performance.
Machine learning (ML) has achieved great breakthroughs in many fields, such as computer vision and speech recognition, and it also gains an increasing attention in geotechnical engineering. However, ...it is often criticized for a lack of interpretability. This study proposes an interpretable sparse dictionary learning (ISDL) approach for selection of suitable soil constitutive models (SCMs) and geotechnical consolidation analysis in a specific site. ISDL is inherently interpretable since it expresses prediction of geotechnical responses (e.g., consolidation settlement) as a weighted summation of many elementary datasets (i.e., dictionary atoms in ISDL). The dictionary atoms are constructed using numerical analyses (e.g., finite element model) with different candidate SCMs and parameters. Interpretability of ISDL is improved by a small number of non-trivial atoms (or SCMs) selected for model prediction using site-specific monitoring data and further enhanced by contribution ranking of the selected SCMs using a game theory-based approach. The proposed method is illustrated using a real reclamation project in Hong Kong, and it is shown to effectively select the most suitable constitutive models for the given site, quantify contributions of the selected models, and significantly improve settlement predictions with rigorously quantified prediction uncertainty, particularly at locations without monitoring or future time steps.
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