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By examining female streamers’ everyday interactions with their viewers and their experiences as showroom livestreamers (xiuchang zhubo) in China’s livestreaming industry, this article adopts—but also re-examines—the premises of relational labour in order to investigate the gendered power relations involved in the showroom livestreaming sector. Based on semi-structured in-depth interviews with female livestreamers, we argue that showroom livestreaming work is contingent on relational labour and constitutes a precarious balancing act. On the one hand, female streamers are positioned in a gendered economy, searching to monetize their production of sexually ambivalent intimacy. On the other hand, through constant negotiation, they try to maintain the correct degree of intimacy in order to avoid violating both platform regulations and the social moral standard. Therefore, the implicitly sexualised and intimate performances undertaken by female streamers are the result of negotiating livestreaming platforms’ technological and economic affordances, the male viewers’ needs for intimate personal interactions, and their own subjectivities. We claim that the economy of aimei, or ambivalent intimacy, represents a deeper form of exploitation, whereby female streamers themselves bear the responsibility to navigate tensions and emotional alienation at the nexus of financial security, sexual desire, and morality.

This paper is devoted to discussing the blow-up problem of the positive solution of the following degenerate parabolic equations: ( r ( u ) ) t = div ( ∣ ∇ u ∣ p ∇ u ) + f ( x , t , u , ∣ ∇ u ∣ 2 ) , ( x , t ) ∈ D × ( 0 , T ∗ ) , ∂ u ∂ ν + σ u = 0 , ( x , t ) ∈ ∂ D × ( 0 , T ∗ ) , u ( x , 0 ) = u 0 ( x ) , x ∈ D ¯ . \left\{\begin{array}{ll}{(r\left(u))}_{t}={\rm{div}}(| \nabla u{| }^{p}\nabla u)+f\left(x,t,u,| \nabla u\hspace{-0.25em}{| }^{2}),& \left(x,t)\in D\times \left(0,{T}^{\ast }),\\ \frac{\partial u}{\partial \nu }+\sigma u=0,& \left(x,t)\in \partial D\times \left(0,{T}^{\ast }),\\ u\left(x,0)={u}_{0}\left(x),& x\in \overline{D}.\end{array}\right. Here p > 0 p\gt 0 , the spatial region D ⊂ R n ( n ≥ 2 ) D\subset {{\mathbb{R}}}^{n}\hspace{0.33em}\left(n\ge 2) is bounded, and its boundary ∂ D \partial D is smooth. We give the conditions that cause the positive solution of this degenerate parabolic problem to blow up. At the same time, for the positive blow-up solution of this problem, we also obtain an upper bound of the blow-up time and an upper estimate of the blow-up rate. We mainly carry out our research by means of maximum principles and first-order differential inequality technique.

The present single-cell RNA sequencing(scRNA-seq) analysis pipelines require a combination of appropriate normalization, dimension reduction, clustering, and specific-gene analysis algorithms, but the rationale for the choice of these algorithms is relatively subjective because of the lack of ground truth assessment conclusions. As the number of captured single-cells increases, the number of different types of noise cells also increases, which can strongly affect the analysis efficiency. For scRNA-seq, a technology that generates data through multi-process operations, the deep generative model should be a good choice for this type of data analysis, allowing simultaneous estimation of multiple unobservable parameters assumed in the data generation process. Hence, in our study, we sequenced a pool of pre-labeled single cells to obtain a batch of scRNA-seq data with main and fine labels, which was then used to evaluate the clustering and specific-gene analysis methods. Afterward, we applied two deep generative models to infer the probabilities of pseudo and impurity cells. And by stepwise removing the inferred noise cells, the clustering performance and the consistency of different specific-gene analysis methods are both greatly improved. After that, we applied Deep-LDA (a latent Dirichlet allocation-based deep generative model) to scRNA-seq data analysis. And this model takes the count matrix as input, and makes the classification and specific gene optimization process mutually dependent, which has more practical sense and simplifies the analysis workflow. At last, we successfully implemented the model with transferred knowledge to make single-cell annotation and verified its superior performance.

It is desirable to develop efficient image rescaling methods to transmit digital images with different resolutions between devices and assure visual quality. In image downscaling, the inevitable loss of high-frequency information makes the reverse upscaling highly ill-posed. Recent approaches focus on joint learning of image downscaling and upscaling (e.g., rescaling). However, existing methods still fail to recover satisfactory high-frequency signals when upscaling. To solve it, we propose high-frequency flow (HfFlow), which learns the distribution of high-frequency signals during rescaling. HfFlow is an overall invertible framework with a conditional flow on the high-frequency space to compensate for the information lost during downscaling. To facilitate finding the optimal upscaling solution, we introduce a reference low-resolution (LR) manifold and propose a cross-entropy Gaussian loss (CGloss) to force the downscaled manifold closer to the reference LR manifold and simultaneously fulfill recovering missing details. HfFlow can be generalized to other scale transformation tasks such as image colorization with its excellent rescaling capacity. Qualitative and quantitative experimental evaluations demonstrate that HfFlow restores rich high-frequency details and outperforms state-of-the-art rescaling methods in PSNR, SSIM, and perceptual quality metrics.

In this work, we studied the wavelength-dependent laser-induced dynamic annealing of single plasmonic nano-antennas using in situ white light spectroscopy. Unexpected back-and-forth motions of rapidly melted single nano-antennas were observed upon excitation with a 532 nm laser, while only gradual opening of nanogaps was found in the case of a 405 nm laser. Theoretical analyses indicate that the dramatic nano-annealing phenomenon was caused by a series of laser-induced multiphysical processes at the nanoscale. It not only leads to the local heating effect, but also induces complex behaviors such as self-accelerated melting, asymmetry-induced nano-photophoretic forces and optical forces. Our work demonstrates the complexity of light–matter interactions at the nanoscale, and provides new possibilities for shaping and manipulating plasmonic nanostructures.

Oysters are hyper-accumulators of copper (Cu) and zinc (Zn) and are a good food source for trace element supplements. However, increasing heavy metal pollution in estuaries and coastal areas has posed a critical threat to oysters and thus led to food safety issues. Here, we assessed if it is possible to obtain oyster varieties with differential metal-accumulated properties through genetic improvement. The narrow-sense heritabilities of Cu and Zn accumulation capabilities and growth traits in Fujian oyster (Crassostrea angulata) were estimated to determine the degree to which Cu and Zn accumulation is under genetic control. In addition, we investigated the trade-offs between Cu/Zn accumulation and some farming performances, including growth-related traits, and the contents of glycogen and eight free amino acids. Moderate estimates were observed for narrow-sense heritability of Cu (0.189 ± 0.061) and Zn (0.373 ± 0.091) accumulation capability, while growth-related traits showed moderate-high heritability (0.168 ± 0.059–0.595 ± 0.116). High-level genetic (0.802 ± 0.080) and phenotypic (0.853 ± 0.012) correlations were detected between Cu and Zn accumulation capability, while correlations between metal accumulation and growth traits were low (−0.023 ± 0.042–0.491 ± 0.200). Moreover, Cu and Zn accumulation in Fujian oyster exhibited no significant influence on the quality traits measured, except for Taurine (Tau). Tau contents in high Cu/Zn accumulated oysters were significantly higher than in low-accumulated oysters, suggesting an important role of Tau in Cu/Zn accumulation. Our results provide important information to guide effective selective breeding of Fujian oysters with specific Cu/Zn accumulation capabilities.

BACKGROUND The COVID-19 outbreak has spurred increasing anti-Asian racism and xenophobia in the United States, which might be detrimental to the psychological well-being of Asian people living in the United States. OBJECTIVE We studied three discrimination-related variables, including (1) experience of discrimination, (2) worry about discrimination, and (3) racism-related social media use during the COVID-19 pandemic among Asians in the United States. We examined how these three variables were related to depression, and how the association between racism-related social media use and depression was moderated by personal experience of and worry about racial discrimination. METHODS A web-based, cross-sectional survey was conducted. A total of 209 people (mean age 33.69, SD 11.31 years; 96/209, 45.93% female) who identified themselves as Asian and resided in the United States were included in the study. RESULTS Experience of discrimination (β=.33, P=.001) and racism-related social media use (β=.14, P=.045) were positively associated with depressive symptoms. Worry about discrimination (β=.13, P=.14) was not associated with depression. Worry about discrimination moderated the relationship between racism-related social media use and depression (β=–.25, P=.003) such that a positive relationship was observed among those who had low and medium levels of worry. CONCLUSIONS The present study provided preliminary evidence that experience of discrimination during the COVID-19 pandemic was a risk factor of depressive symptoms among Asian people in the United States. Meanwhile, racism-related social media use was found to be negatively associated with the well-being of US Asians, and the relationship between social media use and depression was significantly moderated by worry about discrimination. It is critical to develop accessible programs to help US Asians cope with racial discrimination both in real lives and on social media during this unprecedented health crisis, especially among those who have not been mentally prepared for such challenges.

Background The COVID-19 outbreak has spurred increasing anti-Asian racism and xenophobia in the United States, which might be detrimental to the psychological well-being of Asian people living in the United States. Objective We studied three discrimination-related variables, including (1) experience of discrimination, (2) worry about discrimination, and (3) racism-related social media use during the COVID-19 pandemic among Asians in the United States. We examined how these three variables were related to depression, and how the association between racism-related social media use and depression was moderated by personal experience of and worry about racial discrimination. Methods A web-based, cross-sectional survey was conducted. A total of 209 people (mean age 33.69, SD 11.31 years; 96/209, 45.93% female) who identified themselves as Asian and resided in the United States were included in the study. Results Experience of discrimination (β=.33, P=.001) and racism-related social media use (β=.14, P=.045) were positively associated with depressive symptoms. Worry about discrimination (β=.13, P=.14) was not associated with depression. Worry about discrimination moderated the relationship between racism-related social media use and depression (β=–.25, P=.003) such that a positive relationship was observed among those who had low and medium levels of worry. Conclusions The present study provided preliminary evidence that experience of discrimination during the COVID-19 pandemic was a risk factor of depressive symptoms among Asian people in the United States. Meanwhile, racism-related social media use was found to be negatively associated with the well-being of US Asians, and the relationship between social media use and depression was significantly moderated by worry about discrimination. It is critical to develop accessible programs to help US Asians cope with racial discrimination both in real lives and on social media during this unprecedented health crisis, especially among those who have not been mentally prepared for such challenges.

In this study, a method is proposed to carry out food peeling task using our dual-arm robot system with a peeler. First, the problem of peeling a food using robot arms is discussed. Then, a new method for food peeling is introduced, which contains two parts: “ One peeling motion “ in which the robot peels part of a rind or skin through a pre-generated trajectory, and “Rotation motion” where the robot calculates the pose of food for the next “One peeling motion”. The introduced peeling method was implemented into the dual-arm system and then put into test by peeling five types of food. The results prove that the proposed method can peel the skin of various types of food successfully.

The main purpose of the present paper is to study the blow-up problem of a weakly coupled quasilinear parabolic system as follows: \begin{document}$ \left\{ \begin{array}{ll} u_{t} = \nabla\cdot\left(r(u)\nabla u\right)+f(u,v,x,t), & \\ v_{t} = \nabla\cdot\left(s(v)\nabla v\right)+g(u,v,x,t) &{\rm in} \ \Omega\times(0,t^{*}), \\ \frac{\partial u}{\partial\nu} = h(u), \ \frac{\partial v}{\partial\nu} = k(v) &{\rm on} \ \partial\Omega\times(0,t^{*}), \\ u(x,0) = u_{0}(x), \ v(x,0) = v_{0}(x) &{\rm in} \ \overline{\Omega}. \end{array} \right. $\end{document} Here \begin{document}$ \Omega $\end{document} is a spatial bounded region in \begin{document}$ \mathbb{R}^{n} \ (n\geq2) $\end{document} and the boundary \begin{document}$ \partial\Omega $\end{document} of the spatial region \begin{document}$ \Omega $\end{document} is smooth. We give a sufficient condition to guarantee that the positive solution \begin{document}$ (u,v) $\end{document} of the above problem must be a blow-up solution with a finite blow-up time \begin{document}$ t^* $\end{document}. In addition, an upper bound on \begin{document}$ t^* $\end{document} and an upper estimate of the blow-up rate on \begin{document}$ (u,v) $\end{document} are obtained.

2D materials exhibit superior properties in electronic and optoelectronic fields. The wide demand for high-performance optoelectronic devices promotes the exploration of diversified 2D materials. Recently, 2D covalent organic frameworks (COFs) have emerged as next-generation layered materials with predesigned π-electronic skeletons and highly ordered topological structures, which are promising for tailoring their optoelectronic properties. However, COFs are usually produced as solid powders due to anisotropic growth, making them unreliable to integrate into devices. Here, by selecting tetraphenylethylene monomers with photoelectric activity, elaborately designed photosensitive 2D-COFs with highly ordered donor-acceptor topologies are in situ synthesized on graphene, ultimately forming COF-graphene heterostructures. Ultrasensitive photodetectors are successfully fabricated with the COFETBC-TAPT -graphene heterostructure and exhibited an excellent overall performance with a photoresponsivity of ≈3.2 × 107 A W-1 at 473 nm and a time response of ≈1.14 ms. Moreover, due to the high surface area and the polarity selectivity of COFs, the photosensing properties of the photodetectors can be reversibly regulated by specific target molecules. The research provides new strategies for building advanced functional devices with programmable material structures and diversified regulation methods, paving the way for a generation of high-performance applications in optoelectronics and many other fields.

Service robots have developed considerably in recent years. This study aims to propose two approaches for controlling the motion of a service robot as it pours liquid precisely from an unknown container into another unknown container without the need of any external tools. To realize this task, we must resolve two sub-tasks, which are determining the poured volume and controlling the pouring action. Our first proposal concentrates on the target container. The poured volume is calculated using a model of target container and the height of liquid in the target container. The action is controlled using a proportional-derivative controller, which considers the angular speed of the pouring container as a process variable and the poured volume as a control variable. Our second method concentrates on the pouring container. The poured volume is calculated using the relation between the angle of the pouring container and poured volume. The action is controlled with a simple proportional controller that takes the angular speed of the pouring container as a process variable and target angle as a control variable. A point cloud is used to model the two containers. These two methods were implemented in a dualarm robot system for testing, and the results show that both methods are effective for controlling precise pouring tasks.

Objective: To compare the efficacy of medical adhesive and hookwire as CT-guided non-palpable pulmonary nodule (NPN) localization methods before video-assisted thoracoscopic surgery (VATS) resection, and determine the risk factors for common complications during localization. Methods: This was a single-center non-randomized retrospective study. 102 consecutive patients with 109 NPNs were divided into Group A (medical adhesive, 66 patients, 72 nodules) and Group B (hookwire, 36 patients, 37 nodules) before VATS. Patient- and nodule-based characteristics were compared. Logistic regression was performed to identify the risk factors for complications. Results: Localization was successfully performed in all the NPNs. For Group A, the rate of pneumothorax immediately after localization was lower (p = 0.049) and the localization-to-surgery interval was longer (p = 0.011) than Group B. There was no significant difference in rates of hemorrhage after needle withdrawal between the two groups (p = 0.198). Hookwire ( vs medical adhesive) (β = 1.12, p = 0.018), total insertion depth (β = −0.41, p = 0.013), pleura-needle angle (β = −0.04, p = 0.025) and grade of hemorrhage after needle withdrawal (β = −0.96, p = 0.030) were independently associated with pneumothorax, while age (β = −0.94, p = 0.018), tumor size (β = 0.29, p = 0.007) and its distance from the pleural surface (β = 0.14, p = 0.004) were associated with higher grade hemorrhage after needle withdrawal. Conclusion: Compared with hookwire, localization with medical adhesive excelled in lower risk of pneumothorax, a more flexible localization-to-surgery interval, and had similar rates of hemorrhage after needle withdrawal. Hookwire is an independent risk factor of pneumothorax immediately after localization. Advances in knowledge: This study added new clinical evidence to the efficacy of medical adhesive in pre-operative CT-guided NPN localization.

Residues of glyphosate (GLY) are widely detected in aquatic systems, raising potential environmental threats and public health concerns, but the mechanism underlying GLY-induced hepatotoxicity in fish has not been fully elucidated yet. This study was designed to explore the hepatotoxic mechanism using juvenile common carp exposed to GLY for 45 d, and plasma and liver samples were collected at 15 d, 30 d, and 45 d to analyze the assays. First, GLY-induced hepatic damage was confirmed by serum liver damage biomarker and hepatic histopathological analysis. Next, changes in oxidative stress biomarkers, gene expression levels of pro- and anti-inflammatory cytokines, and lipid metabolism-related parameters in collected samples were analyzed to clarify their roles in GLY-induced hepatic damage. Data showed that oxidative stress was an early event during GLY exposure, followed by hepatic inflammatory response. Lipid metabolism disorder was a late event during GLY exposure, as evidenced by overproduced hepatic free fatty acids, enhanced lipogenesis-related gene expression levels, reduced lipolysis-related gene expression levels, and resultant hepatic lipid accumulation. Collectively, these findings demonstrate that GLY induces hepatotoxicity in fish through involvement of oxidative stress, inflammatory response, and lipid metabolism disorder, which are intimately interrelated with each other during GLY exposure.

Acoustic tweezers hold great promise for potential applications in cell sorting due to their noncontact, noninvasive, and simple characteristics. Acoustic tweezers, however, have difficulty in separating the cells of the same size distribution, which hampers their applications. In this paper, we demonstrate that assisted by the targeted microbubble, two kinds of cells with an overlap in size distribution can be efficiently separated by surface acoustic waves. By specifically adhering the targeted microbubbles to MDA-MB-231 cells, the acoustic sensitivity of cells can be improved significantly, leading to the isolation of MDA-MB-231 from MCF-7 cells with an efficiency of 91.2 ± 3.4%. This method extends the diversity of acoustic separation and is capable of separation of particles with the same density and diameter, proving a strategy for specific cell sorting.

Polycarbonate (PC) can be easily crystallized by injecting a very dilute benzene solution of PC directly into liquid nitrogen, and then freeze-drying to remove the solvent. The crystallinities of these prepared samples were characterized by wide-angle X-ray diffraction (WAXD). The results of WAXD studies showed that there is a concentration boundary in very dilute solution for crystallizability of PC: near the boundary concentration, the solution has a lower chain entanglement level, and as a result, crystallizes more quickly and completely than more highly entangled PC. By annealing these fewer-chain-entanglement samples at 190°C for 289 h, crystallinity reaches a maximum value of 79.6%, which is much higher than that of annealing ordinary or other solution-crystallized samples.