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This study aimed to investigate the effects of wet flue gas desulfurization (WFGD) on particulate matter (PM) emissions in coal-fired power plants (CFPPs) using an electrical low-pressure impactor (ELPI). The investigation was conducted on five industrial CFPPs of various loads in China to clarify the influence factors of WFGD on PM10 emissions. After WFGD, the proportion of PM2.5 to PM10 in the outlet flue gas increases, which showed that the WFGD system is selective in the capture of PM, with a significant effect on the capture of large particle sizes. The investigation found that four spray layers have a better effect on the capture of particles than two spray layers. Additionally, the investigation also found that unit load is not the main factor affecting the efficiency of PM10 capture by WFGD. Instead, the factors affecting the capture efficiency of PM10 by WFGD are the inlet flue gas temperature and the dust concentration. Relatively higher inlet flue gas temperature and lower inlet dust concentration will both result in higher emission of PM0.1~1 from the WFGD outlet. These findings suggest that a matched integration of WFGD and CFPP is essential for ultra-low PM emission control and green industry development.

C4 olefins and ethanol are essential chemical raw materials, and efficiently preparing them is a valuable topic. In this paper, in order to explore the influence of different catalyst combinations and temperatures on ethanol conversion and C4 olefin selectivity, firstly, for each catalyst combination, by observing the scatter diagram of ethanol conversion, C4 olefin selectivity and temperature, a polynomial regression model of no more than three times was established. Then, 42 regression equations corresponding to 21 catalyst groups were obtained. Twenty-one kinds of catalyst combinations were grouped by controlling variables. After grouping, the relationship between a single factor and temperature was discussed. Non-interactive two-way ANOVA judged the significance of a single factor, and the control variables among different groups were compared to determine the strong significant factors of ethanol conversion rate and C4 olefin selectivity. For judging the significance of temperature, the input rate of ethanol is ignored based on grouping, and the same catalyst combination is regarded as a repeated test. By single factor analysis, it is finally found that the temperature has higher significance to ethanol conversion rate and 400℃, while the selectivity to C4 olefins is much lower.

Anthocyanins are pigments and nutrients in red pears regulated by BBX family genes. Herein, we characterized a 14-nucleotide deletion mutation in the coding region of thePpBBX24gene from ‘Red Zaosu’ pear (Pyrus pyrifoliaWhite Pear Group), namedPpbbx24-del. Genetic and biochemical approaches were used to compare the roles of PpBBX24 and Ppbbx24-del in anthocyanin accumulation.Ppbbx24-delplayed a positive role in anthocyanin biosynthesis of the ‘Red Zaosu’ pear peel by light treatment. Functional analyses based on overexpression in tobacco and transient overexpression in pear fruit peels showed thatPpbbx24-delpromoted anthocyanin accumulation. Cyanidin and peonidin were major differentially expressed anthocyanins, and transcript levels of some structural genes in the anthocyanin biosynthesis pathway were significantly increased. Protein interaction assays showed that PpBBX24 was located in the nucleus and interacted with PpHY5, whereas Ppbbx24-del was colocalized in the nucleoplasm and did not interact with PpHY5. PpHY5 and Ppbbx24-del had positive regulatory effects on the expression ofPpCHS,PpCHI, andPpMYB10when acting alone, but had cumulative effects on gene activation when acting simultaneously. Alone, PpBBX24 had no significant effect on the expression ofPpCHS,PpCHI, orPpMYB10, whereas it inhibited the activation effects of PpHY5 on downstream genes when it existed with PpHY5. Our study demonstrated that mutant Ppbbx24-del positively regulates the anthocyanin accumulation in pear. The results of this study clarify the mechanism and enrich the regulatory network of anthocyanin biosynthesis, which lays a theoretical foundation forPpbbx24-deluse to create red pear cultivars.

One key technique people use in conversation and collaboration is conversational repair. Self-repair is the recognition and attempted correction of one's own mistakes. We investigate how the self-repair of errors by intelligent voice assistants affects user interaction. In a controlled human-participant study (N =101), participants asked Amazon Alexa to perform four tasks, and we manipulated whether Alexa would "make a mistake'' understanding the participant (for example, playing heavy metal in response to a request for relaxing music) and whether Alexa would perform a correction (for example, stating, "You don't seem pleased. Did I get that wrong?'') We measured the impact of self-repair on the participant's perception of the interaction in four conditions: correction (mistakes made and repair performed), undercorrection (mistakes made, no repair performed), overcorrection (no mistakes made, but repair performed), and control (no mistakes made, and no repair performed). Subsequently, we conducted free-response interviews with each participant about their interactions. This study finds that self-repair greatly improves people's assessment of an intelligent voice assistant if a mistake has been made, but can degrade assessment if no correction is needed. However, we find that the positive impact of self-repair in the wake of an error outweighs the negative impact of overcorrection. In addition, participants who recently experienced an error saw increased value in self-repair as a feature, regardless of whether they experienced a repair themselves.

Despite the importance of maternally selected nests in shaping offspring phenotypes, our understanding of how the nest environment affects embryonic development and offspring traits of most non-avian reptiles is rather limited largely due to the logistical difficulty in locating their nests. To identify the relative contributions of environmental (temporal [seasonal] and spatial [nest-site]) and intrinsic (clutch) factors on embryonic development and offspring traits, we conducted a cross-fostering experiment by swapping eggs between maternally-selected nests of the toad-headed agama (Phrynocephalus przewalskii) in the field. We found that nest environment explained a large proportion of variation in incubation duration, hatching success, and offspring size and growth. In contrast, clutch only explained a small proportion of variation in these embryonic and offspring traits. More significantly, compared with spatial effects, seasonal effects explained more phenotypic variation in both embryonic development and offspring traits. Eggs laid early in the nesting season had longer incubation durations and produced smaller hatchlings with higher post-hatching growth rates than did later-laid eggs. Consequently, hatchlings from early-laid eggs reached larger body sizes prior to winter. In addition, we found that female toad-headed agama did not select nests specific to reaction norms of their own offspring because hatchlings from original or translocated nests had similar phenotypic traits. Overall, our study demonstrates the importance of seasonal variation in nest environments in determining embryonic development and offspring phenotypes, which has not been widely appreciated at least in non-avian reptiles.

Fruit hardening is a new condition in ‘Suli’ pear fruits that affects their commercial value. This study analyzed the cell wall composition, fruit quality and tissue structure of normal and hardened fruit. The results showed that the protopectin, cellulose and hemicellulose content of hardened fruit were not significantly different from normal fruit. However, in hardened fruit, the soluble pectin content was significantly lower compared to normal fruit, and the lignin content was significantly higher compared to normal fruit, especially in the hardened fruit top region. Hardened fruit also displayed significantly higher cellular lignin autofluorescence than normal fruit. Regarding fruit quality, the firmness and titratable acid content in the hardened fruit were significantly higher than in normal fruit, and the stone cell content in the hardened fruit was significantly higher than in normal fruit, especially in the hardened fruit top region. Fruit water, soluble solid and soluble sugar content in the hardened fruit were significantly lower compared to normal fruit. While observing the development of stone cells, the size and density of stone cells in hardened fruits rapidly increased at 24–34 days after flowering (DAF), especially in the hardened fruit top region. It was likely that a significant synthesis of lignin caused a rapid increase in stone cell density, leading to fruit hardening.

Black-tip disorder, an ailment in the fruits of the Hupingzao cultivar of jujube trees (Ziziphus jujuba Mill. ‘Hupingzao’), seriously affects the edible quality of the fruits. To characterize the relationship between the disorder and sugar transport capacity, transportation of soluble sugar in the vascular bundles of Hupingzao fruits was analyzed using UPLC and the fluorescence tracing method. Phloem cell viability of the vascular bundles was also analyzed by staining. Results showed that black-tip disorder mainly occurred from the white-ripe period onwards during the development of Hupingzao fruits, and disease spots only appeared in the blossom end of the fruits. There was a significantly higher rate of large disorder fruits than small disorder fruits. The accumulation and transportation rate of soluble sugar in the blossom end of the fruits was significantly lower than that in the shoulder regions from the white-ripe period onwards. At the same developmental stage, the soluble sugar content in the blossom end of disorder fruits was significantly lower than that in the blossom end of healthy fruits. In disorder fruits, the soluble sugar content of large fruits was lower than that of small fruits. In disorder fruits, phloem activity was weaker in large fruits than small fruits. In summary, the ability of the vascular bundles to transport soluble sugar weakened and sugar supply in the blossom end of the fruits was insufficient to sustain health, and this was likely to cause black-tip disorder from the white-ripe period onwards during the development of Hupingzao fruits.

Low-elevation species can migrate toward higher elevations to survive in a warming world. However, animals' responses to hypoxia when migrating to high elevations have rarely been addressed. To identify the response of low-elevation lizards to high-elevation hypoxia, we collected field body temperatures (Tfb ) and operative temperatures (Te ) of lizards (Eremias argus) from a low-elevation population (1036 m) and a high-elevation population (2036 m), and then determined adult thermal physiology, embryonic development, and hatchling phenotypes after acclimating low-elevation lizards and incubating their eggs in conditions mimicking the low-elevation oxygen condition (18.5% O2 ) and high-elevation oxygen (hypoxic) condition (16.5% O2 ). Our study revealed that Tfb and Te were higher for the low-elevation population compared to the high-elevation population. We also found adults from low elevation acclimated to hypoxia preferred lower body temperatures, but did not show changes in locomotor performance or growth. In addition, hypoxia did not affect embryonic development (hatching time and success) or hatchling phenotypes (body size and locomotor performance). These results suggest that adult lizards from low elevations can respond to hypoxia-induced stress when migrating to high elevations by behaviorally thermoregulating to lower body temperatures in order to sustain normal functions. Similarly, low-elevation embryos can develop normally (with unchanged hatching success and offspring phenotypes) under the high-elevation hypoxic condition. This study highlights that low-elevation populations of a species that inhabits a range of elevations can buffer the impact of high-elevation hypoxic conditions to some degree and thus attain similar fitness to the source population.

Temperature is a crucial environmental factor that can strongly impact animal physiology. Here, we acclimated hatchling of Asian yellow pond turtles (Mauremys mutica) to one of two different temperatures (25 or 30°C) for four weeks to determine temperature acclimation effects on their physiology. All four measured physiological variables (righting time, resting metabolic rate, critical thermal minimum and critical thermal maximum) were significantly affected by temperature acclimation. Turtles acclimated to 25°C righted themselves more slowly and had a lower mean metabolic rate than 30°C-acclimated turtles. Turtles acclimated to 25°C were more resistant to low temperatures, but less resistant to high temperatures than 30°C-acclimated turtles, as measured by critical thermal limits. The thermal resistance range (i.e., the difference between critical thermal minimum and maximum) did not differ between the two acclimation groups. Compared with other semi-aquatic turtles, M. mutica had relatively higher acclimation response ratios for its critical thermal minimum and critical thermal maximum. Our results indicate that acclimation to relatively moderate temperatures could also produce significant responses in the thermal physiology of turtles.

From the perspective of superiority, this article is based on the theory of leadership style, using grounded theory research methods to explore and analyze the impact mechanism of disabled employees’ performance in the local environment. The research results show that: 1) Spiritual leaders can influence their performance by improving the organizational commitment and organizational self-esteem of disabled employees. 2) The influence of spiritual leaders on the performance of disabled employees is affected by organizational support. The research findings reveal the “black box” of the performance impact mechanism of employees with disabilities, enrich and supplement the existing leader theory, provide a preliminary theoretical framework for follow-up related empirical research, and provide theory for organizations to stimulate disability employee performance in management practice.

Family business occupies an important position in the national economy of all countries in the world. The theoretical field has always been controversial about the agency costs of family businesses. This article reviews the agency conflicts in family businesses and the resulting agency costs. Relevant literature found the particularity and complexity of agency costs for family businesses. Finally, we proposed an agenda for future research.

This study proposed the fluidization-like dielectric barrier discharge (DBD) plasma for the remediation of lindane contaminated soil and integrated physical and chemical reaction pathway. Soil particle distribution within the reactor was simulated with Euler-Euler and Gidaspow drag models, and a bipolar pulsed power supply was applied to energize the DBD reactor after full fluidized. The effect of soil particles movement on electric features was discussed in terms of voltage waveforms and Lissajous figures. Lindane degradation was found to be related to electrics parameters and soil properties. Soil samples before and after treatment were analyzed by XRD and SEM methods. A 95.98% lindane decomposition and 0.66 mgsubLindane/sub/h average reaction rate were obtained with 3 wt% CaO injection by pulse power drove fluidization-like DBD after 32 min treatment. Ozone was proved to play a major role during lindane degrading by plasma. The reaction potential pathway of lindane decomposition contains 4 steps, including dehydrogen, dehydrochlorination, and dechlorination, respectively.

Global warming has led to an increase in the frequency, duration, and intensity of heat waves in the summer, which can cause frequent and acute heat stress on ectotherms. Thus, determining how ectothermic animals respond to heat waves has been attracting growing interest among ecologists. However, the physiological and biochemical responses to heat waves in reptiles, especially aquatic reptiles, are still poorly understood. The current study investigated the oxidant physiology, immunity, and expression levels of heat shock proteins (HSP) mRNA after exposure to a simulated heat wave (1 week, 35 ± 4°C), followed by a recovery period (1 week, 28 ± 4°C) in juvenile Asian yellow pond turtle (Mauremys mutica), a widely farmed aquatic turtle in East Asia. The contents of malondialdehyde (MDA) in the liver and muscle were not significantly affected by the heat wave or recovery. Of all antioxidant enzymes, only the activity of glutathione peroxidase (GSH-Px) in muscles increased after heat wave, while the total superoxide dismutase (T-SOD), catalase activity (CAT), and total antioxidant capacity (T-AOC) did not change during the study. The organo-somatic index for the liver and spleen of M. mutica decreased after the heat wave but increased to the initial level after recovery. In contrast, plasma lysozyme activity and serum complement C4 levels increased after the heat wave, returning to the control level after recovery. In addition, heat waves did not alter the relative expression of HSP60, HSP70, and HSP90 mRNA in the liver. Eventually, heat wave slightly increased the IBR/n index. Therefore, our results suggested that heat waves did not lead to oxidative damage to lipids in M. mutica, but deleteriously affected the turtles’ immune organs. Meanwhile, the constitutive levels of most antioxidative enzyme activities, HSPs and enhanced blood immune functions might protect the turtles from the threat of heat waves under the current climate scenarios.

Hepatitis B virus (HBV) vaccines are composed of surface antigen HBsAg that spontaneously assembles into subviral particles. Factors that impede its humoral immunity in 5% to 10% of vaccinees remain elusive. Here, we showed that the low-level interleukin-1 receptor antagonist (IL-1Ra) can predict antibody protection both in mice and humans. Mechanistically, murine IL-1Ra-inhibited T follicular helper (Tfh) cell expansion and subsequent germinal center (GC)-dependent humoral immunity, resulting in significantly weakened protection against the HBV challenge. Compared to soluble antigens, HBsAg particle antigen displayed a unique capture/uptake and innate immune activation, including IL-1Ra expression, preferably of medullary sinus macrophages. In humans, a unique polymorphism in the RelA/p65 binding site of IL-1Ra enhancer associated IL-1Ra levels with ethnicity-dependent vaccination outcome. Therefore, the differential IL-1Ra response to particle antigens probably creates a suppressive milieu for Tfh/GC development, and neutralization of IL-1Ra would resurrect antibody response in HBV vaccine nonresponders.

Contrary to our anticipation, consumption experiences do not always please us; instead, they sometimes impede our well-being. People often regret using their resources unfavorably (i.e., buyers' remorse or impulse buying) or take the pleasure of having something for granted before long (i.e., hedonic adaptation). Given its effects on optimizing positive experiences, positive emotion regulation can be useful for mitigating these issues. The present paper introduces PurPal, a self-administered behavioral intervention technology that enables users to up-regulate their positive emotions in the context of consumption. PurPal provides adaptive questions associated with users' purchase intentions, which stimulate reflection on possible future positive experiences with purchased items. A user study is planned to validate the efficacy of PurPal in a lab setting. The longer-term goal of the current research is to develop behavioral intervention technologies that support users' emotion regulation processes, enhancing their subjective well-being.

The two-stage electrostatic precipitator (ESP) is widely used for indoor air cleaning field, while both the Particle Image Velocimetry (PIV) observations and well-characterized quantitative descriptions are probably scarce. In this work, we propose to use vortex analysis, which is the main quantitative method for flow field, and the relative residence time method (RRT) to evaluate the electrohydrodynamic flow (EHD) in a plate-plate ESP. The effects of electrical energization, pre-charger polarity and primary gas flow velocity are studied. Two vortex indexes sort the particle flow as five patterns and increase almost linearly with applied voltage. Four final particle statuses, penetrated, collected, stagnant and back-mixed are clarified by RRT method. The data generated by RRT are utilized to derive the PIV index for further analysis of the ESP performance. The trend, which rises first and drops later, suggests PIV index is expected to pave a new way to clarify the relationship between the ESP flow patterns and particle collection efficiency.

APOBEC3 protein families, a DNA cytidine deaminase, were up-regulated in multiple tumors. However, the relationship between Hepatocellular carcinoma (HCC) and APOBEC3B (A3B) remains unknown. It has been confirmed that interleukin-6 (IL-6) has significant impacts on oncogenesis of HCC. Here, we reported that the expression of IL-6 was substantially up-regulated by A3B in HepG2 cells. A3B induced IL-6 expression through relocating HuR to enhance the IL-6 mRNA stability. Further analysis indicated that IL-6 also increased the expression of A3B through JAK1/STAT3 signaling pathway, which formed a positive feedback to maintain the continuous expression of A3B and IL-6, and thereby promoted the prolonged non-resolving inflammation. Collectively, these findings suggest that A3B is essential for oncogenesis of HCC, and is a potential target for preventive intervention.

Cracking is caused by physiological stress during the development of jujube fruit, and this causes considerable economic losses to fruit producers. The aim of this study was to clarify the mechanisms of water entry into the fruit and the events that lead to cracking. Differences in water absorption by fruit stalks and surfaces were observed in a cracking-sensitive variety (Ziziphus jujuba Mill. ‘Hupingzao’) and a cracking-resistant variety (Ziziphus jujuba Mill. ‘Yuanlingzao’). The response of the fruit surface to water absorption was studied, and the relationship between stomatal characteristics and cracking was analyzed. The cracking rate of ‘Hupingzao’ was higher during the coloring period. The relative amount of water absorbed through the fruit stalk of ‘Yuanlingzao’ after 10 h was 1.22 times higher than that of ‘Hupingzao’ during the coloring period. The rate of water absorption through the fruit surface of ‘Hupingzao’ was higher than that of ‘Yuanlingzao’ during the coloring period (3.73 and 3.04, respectively). Water was transported by the vascular bundle after entering the fruit through the fruit stalk, but was mainly distributed around the stomata of the epidermis and near-surface cells following entry through the fruit surface. After water was absorbed by the fruit surface, surface and stomatal cracks in ‘Hupingzao’ were apparent, and the degree of cracking of the stomata worsened with increasing water absorption time. The surface of ‘Yuanlingzao’ appeared cracked with increasing immersion time, but stomatal changes were not obvious. The stomatal size and aperture in the cracking-resistant variety of jujube fruit were lower than those in the cracking-sensitive variety. Stomatal size was positively correlated with the rate of fruit cracking. Water absorption through the surface was the main factor that induced fruit cracking. Stomatal characteristics, as well as the increased and deepened fruit surface microcracks caused by stomatal water absorption, were the primary factors related to cracking.

Recent attention has been given to the role of emotion regulation in promoting well-being. Although various approaches have been established to design for emotion in design research and HCI, there is only little knowledge on how to support the process of regulating user emotions through design. The paper introduces a framework that delineates 17 emotion regulation strategies based on the theories of emotion regulation. The framework supports an understanding of emotion regulation strategies by enabling designers to compare differences and overlaps of the strategies. The paper describes the framework and its development process along with design examples. Implications and future research steps are discussed.

Fruit cracking is a key problem restricting the development of the jujube (Ziziphus jujuba) industry, and is closely related to the distribution of the wax layer on the surface of the fruit. Three jujube cultivars with different levels of cracking resistance, namely 'Popozao', 'Banzao', and 'Hupingzao', were selected for comparison. Cracks on the cuticular membrane (CM) of 'Hupingzao' widened and deepened during the coloring period. The wax level of highly cracking-resistant 'Popozao' was significantly higher than that of 'Hupingzao' during the fruit coloring period. The fruit wax composition of the three jujube cultivars were quite similar, consisting mainly of alkanes, triterpenoids, aldehydes, amines, phenols, esters, ketones, fatty acids, primary alcohols, and other, unclassified compounds. Fatty acids, primary alcohols, and alkanes were the predominant fruit wax compounds of the three cultivars. We further analyzed the carbon chain length of aliphatic compounds and found that the concentration of fatty acids in 'Popozao' was significantly lower than that in 'Banzao' and 'Hupingzao' during the coloring period. Moreover, C28-30 were the most abundant primary alcohols during fruit development. Highly cracking-resistant cultivar 'Popozao' contains more very-long-chain alkanes and aldehydes (carbon atom >20) than 'Banzao' and 'Hupingzao' during the coloring period. In addition, we assessed the expression levels of 11 genes involved in fatty acid biosynthesis, elongation, and degradation, and in wax biosynthesis. Gene expression analysis indicated that KCS1, CER1, CYP86B1, and CYP86A play crucial roles in wax formation on jujube fruit. In conclusion, fruit cracking was correlated with whether wax synthesis is coordinated with fruit enlargement and'Popozao' has a stronger ability to synthesize very-long-chain alkanes and aldehydes. Understanding the diff ;erences in the cuticular wax and the activities of the corresponding genes in jujube cultivars with different sensitivities to cracking will provide a specific way to prevent fruit cracking.

Wide Electrostatic Precipitator (having plate-to-plate spacing 400 mm or more) is one of a promising ways to improve existing ESPs, yet its large-scale application has been limited because of potential collection efficiency reduction. This article focus on study the electrohydrodynamic flow inside the ESP and the particle collection efficiency by using Particle Image Velocimetry and Electrical Low Pressure Impactor respectively when several different electrode geometries were applied, in order to increase wide ESP efficiency. Results showed that geometry with juxtaposed high voltage wires provided best performance of the wide ESP (both in collection efficiency and running cost) among our tests.

ObjectiveAPOBEC3B (A3B), a cytidine deaminase acting as a contributor to the APOBEC mutation pattern in many kinds of tumours, is upregulated in patients with hepatocellular carcinoma (HCC). However, APOBEC mutation patterns are absent in HCC. The mechanism of how A3B affects HCC progression remains elusive.DesignA3B ­promoter luciferase reporter and other techniques were applied to elucidate mechanisms of A3B upregulation in HCC. A3B overexpression and knockdown cell models, immunocompetent and immune-deficient mouse HCC model were conducted to investigate the influence of A3B on HCC progression. RNA­seq, flow cytometry and other techniques were conducted to analyse how A3B modulated the cytokine to enhance the recruitment of myeloid­-derived suppressor cells (MDSCs) and tumour­-associated macrophages (TAMs).ResultsA3B upregulation through non-classical nuclear factor-κB (NF-κB)signalling promotes HCC growth in immunocompetent mice, associated with an increase of MDSCs, TAMs and programmed cell death1 (PD1) exprssed CD8+ T cells. A CCR2 antagonist suppressed TAMs and MDSCs infiltration and delayed tumour growth in A3B and A3BE68Q/E255Q­ expressing mouse tumours. Mechanistically, A3B upregulation in HCC depresses global H3K27me3 abundance via interaction with polycomb repressor complex 2 (PRC2) and reduces an occupancy of H3K27me3 on promoters of the chemokine CCL2 to recruit massive TAMs and MDSCs.ConclusionOur observations uncover a deaminase-independent role of the A3B in modulating the HCC microenvironment and demonstrate a proof for the concept of targeting A3B in HCC immunotherapy.

Exhaustion of cytotoxic effector natural killer (NK) and CD8+ T cells have important functions in the establishment of persistent viral infections, but how exhaustion is induced during chronic hepatitis C virus (HCV) infection remains poorly defined. Here we show, using the humanized C/OTg mice permissive for persistent HCV infection, that NK and CD8+ T cells become sequentially exhausted shortly after their transient hepatic infiltration and activation in acute HCV infection. HCV infection upregulates Qa-1 expression in hepatocytes, which ligates NKG2A to induce NK cell exhaustion. Antibodies targeting NKG2A or Qa-1 prevents NK exhaustion and promotes NK-dependent HCV clearance. Moreover, reactivated NK cells provide sufficient IFN-γ that helps rejuvenate polyclonal HCV CD8+ T cell response and clearance of HCV. Our data thus show that NKG2A serves as a critical checkpoint for HCV-induced NK exhaustion, and that NKG2A blockade sequentially boosts interdependent NK and CD8+ T cell functions to prevent persistent HCV infection., Immune cells may become less responsive, or ‘exhausted’, upon chronic viral infection, but the underlying mechanism and crosstalk are still unclear. Here the authors show that, upon chronic hepatitis C virus (HCV) infection, natural killer cell exhaustion is induced by NKG2A signalling to instruct downstream exhaustion of CD8+ T cells and HCV persistence.

The plasma sparker has been applied in oceanic high-resolution seismic exploration for decades. Normally it is towed on the water surface. This is suitable for shallow water, but if the water depth is great, the resolution will decrease dramatically, especially in the horizontal direction. This paper proposes the concept of a deep-towed plasma sparker and presents an experimental study of plasma sparker performance in terms of electric parameters, bubble behavior, and acoustic characteristics. The results show that hydrostatic pressure at a source depth ranging from 1 to 2000 m has a negligible influence on the electric parameters but a strong influence on bubble behavior, wherein both the maximum bubble radius and oscillation period are decreased. The collapse pulse vanishes when the source depth reaches 1000 m or deeper, and no bubble oscillation can be distinguished. The source level (evaluated by the expansion pulse) is also decreased as the source depth increases; moreover, the greater the discharge energy, the smaller the source level loss. The discharge energy per electrode should be greater than 20 J for the deep-towed plasma sparker, which can make the source level loss induced by hydrostatic pressure smaller than the transmission loss. The fast Fourier transform (FFT) results show that the dominant energy is around 20 kHz, which is mainly induced by the expansion pulse and its oscillation. According to the simulation results, the fundamental frequency of the acoustic waveform increases with source depth in accord with a log linear trend, and also reaches tens of kilohertz in deep water. So, before the development of deep-towed plasma sparker, a new technical solution will need to be developed to solve this problem.