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Lipids play crucial roles in many biological processes. Mapping spatial distributions and examining the metabolic dynamics of different lipid subtypes in cells and tissues are critical to better understanding their roles in aging and diseases. Commonly used imaging methods (such as mass spectrometry-based, fluorescence labeling, conventional optical imaging) can disrupt the native environment of cells/tissues, have limited spatial or spectral resolution, or cannot distinguish different lipid subtypes. Here we present a hyperspectral imaging platform that integrates a Penalized Reference Matching algorithm with Stimulated Raman Scattering (PRM-SRS) microscopy. Using this platform, we visualize and identify high density lipoprotein particles in human kidney, a high cholesterol to phosphatidylethanolamine ratio inside granule cells of mouse hippocampus, and subcellular distributions of sphingosine and cardiolipin in human brain. Our PRM-SRS displays unique advantages of enhanced chemical specificity, subcellular resolution, and fast data processing in distinguishing lipid subtypes in different organs and species.

Computational thinking (CT) has become an important skill for the new generation, and CT teaching games have been introduced to lower the barriers that novices face in learning programming. However, despite the prevalence of and demand for these games, little is known about the effectiveness of their design or about the principles that are conducive to learning using these games. In this article, we present a project in which we triangulated design research with controlled experiments to evaluate the effectiveness of a computational puzzle design (CPD) framework in guiding the development of CT teaching games for children. Using CT tests, game logs, and a survey, we evaluated the learning outcomes of and engagement with various versions of the game "LittleWorld," designed based on various principles of the CPD framework and implemented in Chinese elementary education (n = 202). The results validate the CPD framework and demonstrate that it is a practical and systematic tool for designing CT teaching games. The findings of this study provide design implications concerning (1) the application of meta-gaming and (2) how serious game design research should be conducted.

Lipid metabolism plays crucial roles during aging processes, but how it is regulated by diets and how it interplays with aging still remain unclear. We proposed a new optical imaging platform by integrating heavy water (D2 O) probing with stimulated Raman scattering (DO-SRS) microscopy, for the first time, to directly visualize and quantify lipid metabolism regulated by different diets and insulin signaling pathway in Drosophila fat body during aging. We found that calorie restriction, low protein diet, and (moderately) high protein and high sucrose diets enhanced lipid turnover in flies at all ages, while (moderately) high fructose and glucose diets only promoted lipid turnover in aged flies. The measured lipid turnover enhancements under diverse diets were due to different mechanisms. High protein diet shortened the lifespan while all other diets extended the lifespan. Downregulating the insulin signaling pathway enhanced lipid turnover, which is likely related to lifespan increase, while upregulating insulin signaling pathway decreased lipid turnover that would shorten the lifespan. Our study offers the first approach to directly visualize spatiotemporal alterations of lipid turnover in aging Drosophila in situ, for a better understanding of the interconnections between lipid metabolism, diets, and aging.

We develop a high-throughput technique to relate positions of individual cells to their three-dimensional (3D) imaging features with single-cell resolution. The technique is particularly suitable for nonadherent cells where existing spatial biology methodologies relating cell properties to their positions in a solid tissue do not apply. Our design consists of two parts, as follows: recording 3D cell images at high throughput (500 to 1,000 cells/s) using a custom 3D imaging flow cytometer (3D-IFC) and dispensing cells in a first-in-first-out (FIFO) manner using a robotic cell placement platform (CPP). To prevent errors due to violations of the FIFO principle, we invented a method that uses marker beads and DNA sequencing software to detect errors. Experiments with human cancer cell lines demonstrate the feasibility of mapping 3D side scattering and fluorescent images, as well as two-dimensional (2D) transmission images of cells to their locations on the membrane filter for around 100,000 cells in less than 10 min. While the current work uses our specially designed 3D imaging flow cytometer to produce 3D cell images, our methodology can support other imaging modalities. The technology and method form a bridge between single-cell image analysis and single-cell molecular analysis.

Triple negative breast cancer (TNBC) is a particularly aggressive cancer subtype that is difficult to diagnose due to its discriminating epidemiology and obscure metabolome. For the first time, 3D spatial and chemometric analyses uncover the unique lipid metabolome of TNBC under the tandem modulation of two key metabolites - insulin and methionine - using non-invasive optical techniques. By conjugating heavy water (D2O) probed Raman scattering with label-free two-photon fluorescence (TPF) microscopy, we observed altered de novo lipogenesis, 3D lipid droplet morphology, and lipid peroxidation under various methionine and insulin concentrations. Quantitative interrogation of both spatial and chemometric lipid metabolism under tandem metabolite modulation confirms significant interaction of insulin and methionine, which may prove to be critical therapeutic targets, and proposes a powerful optical imaging platform with subcellular resolution for metabolic and cancer research.

Emerging studies have shown that lipid metabolism plays an important role in aging. High resolution in situ imaging of lipid metabolic dynamics inside cells and tissues affords a novel and potent approach for understanding many biological processes such as aging. Here we established a new optical imaging platform that combines D2O-probed stimulated Raman scattering (DO-SRS) imaging microscopy and a Drosophila model to directly visualize metabolic activities in situ during aging. The sub-cellular spatial distribution of de novo lipogenesis in the fat body was quantitatively imaged and examined. We discovered a dramatic decrease in lipid turnover in 35-day-old flies. Decreases in protein turnover occurred earlier than lipids (25-day vs. 35-day), and there are many proteins localized on the cell and lipid droplet membrane. This suggests that protein metabolism may act as a prerequisite for lipid metabolism during aging. This alteration of maintenance of protein turnover indicates disrupted lipid metabolism. We further found a significantly higher lipid turnover rate in large LDs, indicating more active metabolism in large LDs, suggesting that large and small LDs play different roles in metabolism to maintain cellular homeostasis. This is the first study that directly visualizes spatiotemporal alterations of lipid (and protein) metabolism in Drosophila during the aging process. Our study not only demonstrates a new imaging platform for studying lipid metabolism, but also unravels the important interconnections between lipid metabolism and aging.

This article explores how platforms reorganize our sense of everyday life. The platformization of everyday life means a changing relation to what we do in our daily lives, not only in China, but in every country in which digital platforms are becoming more relevant by the day. Using TikTok in China as our point of departure, we discuss the role of platform time and the abstracted audience.

The short-video platform TikTok/Douyin becomes a space not only for individuals to express and articulate their interests, but also for the authorities to negotiate with the public on various ideological boundaries. This article specifically examines a Douyin campaign in which the platform attempts to prescribe a standard of body exposure that falls within the tolerance level of the authorities and, meanwhile, favours users' interests to gain support. To conceptualize such discursive negotiations and the relevant tactics, we propose the term 'discursive concession' to describe the process of compromise by temporarily challenging, obscuring, and rearticulating the discursive boundary, eventually legitimizing the subordinated discourse by aligning it with the dominant ideological logic. By analysing discourses of representative short videos and comments, we identified three tactics of discursive concession: cooptation, hijacking, and normalization. They respectively describe how dominant, subordinated, and middle powers leverage each other to push the discursive boundary forward. [ABSTRACT FROM AUTHOR]

This study is concerned with the incorporation of TikTok by Filipino musicians in their performances, promotion strategies, and other career-related endeavors. As the music artists are compelled, whether consciously or otherwise, to adhere to the logics of the platform, we critically evaluate its implications on their experiences as creative workers. As revealed, the use of TikTok by Filipino musicians fosters the construction of a new cultural logic and format that enhances music content and narratives as they engage in novel creative pursuits as well as participate in nascent forms of audience relations. Yet the prevalence of TikTok use within the music industry also engenders a new range of obligations that reinforce existing pressures on musicians. This study sheds light on the ambivalent role of TikTok as a platform that could potentially liberate and amplify independent and creative cultural production while also generating new sources of tension for creative workers. [ABSTRACT FROM AUTHOR]

Studies of digital platforms have critically examined the exploitation and low paid condition of creative labour in cultural industries. This study aims to empirically explore the motivation behind why producers/consumers, key opinion leaders, or wanghong are still devoted to producing and posting videos on the short video platform Douyin, which is the Chinese version of Tik Tok, despite the precarious condition. Leveraging on Bourdieu's concept of cultural capitals and the interchangeability of capitals, this paper argues that Douyin provides the possibility for different wanghong to pursue their own intended capitals, which are not just economic capital, but also social, symbolic, and cultural capital. Under a relatively close environment of China, the flexibility and interchangeability of capital gain have at least become an alternative for these wanghong to explore their creativity and fulfil their desires. [ABSTRACT FROM AUTHOR]

This paper discusses the cultural implications of the assimilation of Hong Kong movie production in the process of China–Hong Kong coproductions. Local Hong Kong cultural products tend to be stripped of their local characteristics to cater to the Chinese market when prosperous businesses become based in China. Moreover, distinctive cultural resources in the Hong Kong movie industry, such as techniques, professionals, and intellectual property (IP), are assimilated and coopted by China's cultural industry to ensure the success of its future development. This assimilation may result in cultural conflict, which was indicated by the reaction of Hong Kong audiences to China's embezzlement of their cultural products. This study analyzes three animated movies in the McDull series through focus group interviews with movie investors and audiences in Hong Kong and China. The findings show that assimilation driven by economic factors induces negative sentiment in Hong Kong audiences as they witness the assimilation of their nostalgic icons. Based on these findings, the ramifications of such assimilation for cultural dynamics are considered. [ABSTRACT FROM AUTHOR]

We develop a high-throughput technique to relate positions of individual cells to their three-dimensional (3D) imaging features with single-cell resolution. The technique is particularly suitable for nonadherent cells where existing spatial biology methodologies relating cell properties to their positions in a solid tissue do not apply. Our design consists of two parts, as follows: recording 3D cell images at high throughput (500 to 1,000 cells/s) using a custom 3D imaging flow cytometer (3D-IFC) and dispensing cells in a firstin–first-out (FIFO) manner using a robotic cell placement platform (CPP). To prevent errors due to violations of the FIFO principle, we invented a method that uses marker beads and DNA sequencing software to detect errors. Experiments with human cancer cell lines demonstrate the feasibility of mapping 3D side scattering and fluorescent images, as well as two-dimensional (2D) transmission images of cells to their locations on the membrane filter for around 100,000 cells in less than 10 min. While the current work uses our specially designed 3D imaging flow cytometer to produce 3D cell images, our methodology can support other imaging modalities. The technology and method form a bridge between single-cell image analysis and single-cell molecular analysis. [ABSTRACT FROM AUTHOR]