Verticillium dahliae isolates are most virulent on the host from which they were originally isolated. Mechanisms underlying these dominant host adaptations are currently unknown. We sequenced the ...genome of V. dahliae Vd991, which is highly virulent on its original host, cotton, and performed comparisons with the reference genomes of JR2 (from tomato) and VdLs.17 (from lettuce).
Pathogenicity-related factor prediction, orthology and multigene family classification, transcriptome analyses, phylogenetic analyses, and pathogenicity experiments were performed.
The Vd991 genome harbored several exclusive, lineage-specific (LS) genes within LS regions (LSRs). Deletion mutants of the seven genes within one LSR (G-LSR2) in Vd991 were less virulent only on cotton. Integration of G-LSR2 genes individually into JR2 and VdLs.17 resulted in significantly enhanced virulence on cotton but did not affect virulence on tomato or lettuce. Transcription levels of the seven LS genes in Vd991 were higher during the early stages of cotton infection, as compared with other hosts. Phylogenetic analyses suggested that G-LSR2 was acquired from Fusarium oxysporum f. sp. vasinfectum through horizontal gene transfer.
Our results provide evidence that horizontal gene transfer from Fusarium to Vd991 contributed significantly to its adaptation to cotton and may represent a significant mechanism in the evolution of an asexual plant pathogen.
Psychological health problems, especially emotional disorders, are common among adolescents. The epidemiology of emotional disorders is greatly influenced by stressful events. This study sought to ...assess the prevalence rate and socio-demographic correlates of depressive and anxiety symptoms among Chinese adolescents affected by the outbreak of COVID-19. We conducted a cross-sectional study among Chinese students aged 12–18 years during the COVID-19 epidemic period. An online survey was used to conduct rapid assessment. A total of 8079 participants were involved in the study. An online survey was used to collect demographic data, assess students’ awareness of COVID-19, and assess depressive and anxiety symptoms with the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder (GAD-7) questionnaire, respectively. The prevalence of depressive symptoms, anxiety symptoms, and a combination of depressive and anxiety symptoms was 43.7%, 37.4%, and 31.3%, respectively, among Chinese high school students during the COVID-19 outbreak. Multivariable logistic regression analysis revealed that female gender was the higher risk factor for depressive and anxiety symptoms. In terms of grades, senior high school was a risk factor for depressive and anxiety symptoms; the higher the grade, the greater the prevalence of depressive and anxiety symptoms. Our findings show there is a high prevalence of psychological health problems among adolescents, which are negatively associated with the level of awareness of COVID-19. These findings suggest that the government needs to pay more attention to psychological health among adolescents while combating COVID-19.
This paper presents an experimental study on a semi-active hybrid energy storage system consisting of a battery pack and a supercapacitor pack for electric vehicle application. First, a real-time ...energy management control strategy based on a combination of filtering and fuzzy logic controller is proposed. The main advantage of the proposed control strategy is that the peak current of the battery can be obviously reduced while ensuring the voltage of the supercapacitor fluctuates within a certain desired range. Second, a 30 kW rated power experimental platform is constructed, in which only one dc/dc converter is used to regulate the power flow between the battery and the supercapacitor. Finally, a corrected battery fade model, which can accurately match the studied battery, is used to analyze the battery fade behavior. The results reveal that the battery capacity fade cost of the hybrid energy storage system can be reduced by 44.42%, 30.44%, and 57.16% compared with the sole battery storage under new European drive cycle, highway driving cycle, and Indian urban driving cycle, three driving cycles, respectively.
The shape-selective catalysis enabled by zeolite micropore's molecular-sized sieving is an efficient way to reduce the cost of chemical separation in the chemical industry. Although well studied ...since its discovery, HZSM-5's shape-selective capability has never been fully exploited due to the co-existence of its different-sized straight channels and sinusoidal channels, which makes the shape-selective p-xylene production from toluene alkylation with the least m-xylene and o-xylene continue to be one of the few industrial challenges in the chemical industry. Rather than modifications which promote zeolite shape-selectivity at the cost of stability and reactivity loss, here inverse Al zoned HZSM-5 with sinusoidal channels predominantly opened to their external surfaces is constructed to maximize the shape-selectivity of HZSM-5 sinusoidal channels and reach > 99 % p-xylene selectivity, while keeping a very high activity and good stability ( > 220 h) in toluene methylation reactions. The strategy shows good prospects for shape-selective control of molecules with tiny differences in size.
COVID-19 is associated with 5.1% mortality. Although the virological, epidemiological, clinical, and management outcome features of COVID-19 patients have been defined rapidly, the inflammatory and ...immune profiles require definition as they influence pathogenesis and clinical expression of COVID-19. Here we show lymphopenia, selective loss of CD4+ T cells, CD8+ T cells and NK cells, excessive T-cell activation and high expression of T-cell inhibitory molecules are more prominent in severe cases than in those with mild disease. CD8+ T cells in patients with severe disease express high levels of cytotoxic molecules. Histochemical studies of lung tissue from one fatality show sub-anatomical distributions of SARS-CoV-2 RNA and massive infiltration of T cells and macrophages. Thus, aberrant activation and dysregulation of CD8+ T cells occur in patients with severe COVID-19 disease, an effect that might be for pathogenesis of SARS-CoV-2 infection and indicate that immune-based targets for therapeutic interventions constitute a promising treatment for severe COVID-19 patients.
The coronavirus disease 2019 (COVID-19) outbreak impacts physical and mental health. The purpose of this study was to explore the association between the levels of social support and mental health ...among Chinese adolescents during the outbreak.
A total of 7,202 adolescents aged 14–18 years completed online survceys from March 8 to 15, 2020, in China. Researchers assessed the associations between depression symptoms (Patient Health Questionnaire-9), anxiety symptoms (Chinese version of the 7-item Generalized Anxiety Disorder scale), and social support (Social Support Rate Scale).
COVID-19 exposure was associated with a higher prevalence of depression symptoms (odds ratio OR = 1.38, 95% confidence interval CI: 1.14–1.66) and anxiety symptoms (OR = 1.26, 95% CI: 1.04–1.52). Only 24.6% of adolescents reported high levels of social support. Most adolescents (70%) reported medium levels of support, and 5.4% reported low support. Low support was associated with higher prevalence of depression (OR = 4.24, 95% CI: 3.38–5.33) and anxiety symptoms (OR = 3.18, 95% CI: 2.54–3.98), while controlling for gender, grade, living situation, and COVID-19 exposure; similarly, medium support was associated with higher prevalence of depression (OR = 2.79, 95% CI: 2.48–3.15) and anxiety (OR = 2.19, 95% CI: 1.94–2.48) symptoms.
This study indicates there is a higher prevalence of mental health problems among adolescents with medium and low levels of social support in China during the outbreak of COVID-19.
The ongoing COVID-19 pandemic has negatively influenced the global tourism industry. Despite the documented negative impacts of diseases on tourism demand and people's perceived health risk, ...researchers have seldom examined the psychological responses of tourists travelling during an infectious disease outbreak. We therefore conducted three studies to examine this key aspect, and our findings indicate that tourists have a strong negative emotional reaction towards disadvantaged tourism-related prices in response to a high (vs low) infectious disease threat. Furthermore, risk aversion acts as an underlying mechanism driving this effect: tourists are more risk aversive under the threat of an infectious disease, which consequently magnifies their negative emotional reaction. At last, theoretical and practical implications of these findings for tourism are discussed.
•Investigate the role of infectious diseases on tourists' psychology during a trip•Focus on tourists' emotional responses to disadvantaged price inequality•Examines risk aversion as the underlying mechanism•Use experimental design to examine the impact of disease threat
Graphene as a novel material has laid a foundation for its applications in optical fiber sensors, due to its unique properties, especially the optical properties. On the other hand, optical fiber ...sensors have received world-wide attention due to their high sensitivity, small size, good anti-electromagnetism disturbance ability and other potential advantages. In this paper, the developments of graphene in the applications of optical fiber sensors were reviewed from four aspects. Firstly, the common preparation methods of graphene were introduced. Next, the optical properties of graphene have been concluded. And then, some typical optical fiber chemical and biological sensors based on graphene, such as temperature sensors, biological sensors and gas sensors, were reviewed. It was shown that graphene had a great potential in the optical fiber sensing technology. Furthermore, the deficiencies and challenges of the graphene in the applications of optical fiber sensors were analyzed. In a whole, the unique advantages of graphene have present their versatility and importance in the application fields of optical fiber sensors.
Exceptionally homogeneous and ultrathin COF membranes were successfully fabricated using exfoliated COF nanosheets with uniform perforations as membrane building blocks. The COF membranes showed ...highly permeable performance due to the ultrafast molecular diffusion through the perforations of the COF nanosheets and the excellent thermal stability due to the robust covalent bonds in the framework.
•Ce (Mn) incorporation improved the activity and hydrothermal stability of Cu-SSZ-39.•More active CuO crystallites and stronger acidity contribute high activity after Ce/Mn addition.•Stable ...structure, acidity and less large Cu oxides promote MnCu-SSZ-39 hydrothermally stable.•Cu2+ ion re-distribution to ion exchange sites during hydrothermal process over MnCu-SSZ-39.•NH3-SCR reaction over MnCu-SSZ-39 follows L–H”, E–R, and “Fast SCR” mechanisms.
In this work, Ce and Mn were added to Cu-SSZ-39 zeolites by ion-exchange process, and their activity performance for selective catalytic reduction of NOx with ammonia (NH3-SCR), especially hydrothermal stability (hydrothermal aging at 750, 800, 850 °C) was investigated systematically. It is found that the addition of Ce and Mn, Mn more evidently, both can greatly improve the activity of Cu-SSZ-39 catalyst. Moreover, MnCu-SSZ-39 catalyst have shown superior hydrothermal stability compared with Cu-SSZ-39 catalyst, and outstandingly its activity is not only not decreased significantly like Cu-SSZ-39 but improved obviously after hydrothermal aging at as high as 850 °C. The high and improved activity of Ce and Mn added Cu-SSZ-39 is ascribed to more active CuO crystallites formation in the inner channel and higher acidity strength. The superior hydrothermal stability of MnCu-SSZ-39 may be due to its well-preserved structure and acid density even after hydrothermal aging at as high as 850 °C. Moreover, during the hydrothermal aging process, not only Cu oxides aggregation is inhibited, but also more Cu2+ ion species are induced to ion exchange sites in MnCu-SSZ-39, which may account for its excellent hydrothermal stability (even higher than the activity of fresh samples). The mechanism analysis has shown NH3-SCR reaction over Cu-SSZ-39 and CeCu-SSZ-39 samples follow the “Langmuir–Hinshelwood” (L-H) mechanism, while on MnCu-SSZ-39, it follows both “L–H” and “Eley–Rideal” (E–R) mechanisms, which may also be another reason for its excellent activity and hydrothermal stability. Moreover, “Fast SCR” mechanisms also occur and contribute over hydrothermal aged A-MnCu-SSZ-39 sample, in addition to “L-H” and “E-R” mechanisms. Thus, the easily prepared MnCu-SSZ-39 catalyst has shown the excellent activity and super hydrothermal stability, with 90% NO conversion at 245 °C and broader temperature window of 245 °C to 550 °C, even after hydrothermal aging at 850 °C, therefore indicate great potential for future application in NOx purifying from diesel engine exhaust.
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