Weakly Supervised Classification for Nasopharyngeal Carcinoma with Transformer in Whole Slide Images.

Pathological examination of nasopharyngeal carcinoma (NPC) is an indispensable factor for diagnosis, guiding clinical treatment and judging prognosis. Traditional and fully supervised NPC diagnosis algorithms require manual delineation of regions of interest on the gigapixel of whole slide images (WSIs), which however is laborious and often biased. In this paper, we propose a weakly supervised framework based on Tokens-to-Token Vision Transformer (WS-T2T-ViT) for accurate NPC classification with only a slide-level label. The label of tile images is inherited from their slide-level label. Specifically, WS-T2T-ViT is composed of the multi-resolution pyramid, T2T-ViT and multi-scale attention module. The multi-resolution pyramid is designed for imitating the coarse-to-fine process of manual pathological analysis to learn features from different magnification levels. The T2T module captures the local and global features to overcome the lack of global information. The multi-scale attention module improves classification performance by weighting the contributions of different granularity levels. Extensive experiments are performed on the 802-patient NPC and CAMELYON16 dataset. WS-T2T-ViT achieves an area under the receiver operating characteristic curve (AUC) of 0.989 for NPC classification on the NPC dataset. The experiment results of CAMELYON16 dataset demonstrate the robustness and generalizability of WS-T2T-ViT in WSI-level classification.

Relationship of black soldier fly larvae (BSFL) gut microbiota and bioconversion efficiency with properties of substrates.

Treating food waste using black soldier fly larvae (BSFL) is widely regarded as a promising nature-based measure. This study explored the influence of food waste particle sizes on substrate properties and its subsequent effects on bioconversion efficiency and gut microbiota. The results indicated that particle sizes mainly ranging from 4 mm to 10 mm (T1) significantly increased the weight loss rate of food waste by 35 % and larval biomass by 38 % compared to those in T4 (particle sizes mostly less than 2 mm) and promoted the bioconversion of carbon and nitrogen into larvae and gases. Investigation of substrates properties indicated that the final pH value of T1 was 7.79 ± 0.10, with Anaerococcus as the predominant substrate microorganism (relative abundance: 57.4 %), while T4 exhibited a final pH value of 5.71 ± 0.24, with Lactobacillus as the dominant microorganism (relative abundance: 95.2 %). Correlation analysis between substrate chemical properties and microbial community structure unveiled a strong relationship between substrate pH and the relative abundance of Anaerococcus and Lactobacillus. Furthermore, beneficial microorganisms such as Lactobacillus and Enterococcus colonized the BSFL gut of T1, while pathogenic bacterium Morganella, detrimental to BSFL gut function, was enriched in T4 (relative abundance: 60.9 %). Nevertheless, PCA analysis indicated that alterations in the gut microbial community structure may not be attributed to the substrate microorganisms. This study establishes particle size as a crucial parameter for BSFL bioconversion and advances understanding of the relationship between gut microbiota and substrate microbiota.

Revealing the effects of fermented food waste on the growth and intestinal microorganisms of black soldier fly (Hermetia illucens) larvae.

The escalating global food waste (FW) issues necessitate sustainable management strategies. Black soldier fly larvae (BSFL) offer a promising solution for FW management by converting organic matter into insect protein. However, the fermentation of FW during production, collection, and transportation induces changes in FW's physicochemical properties and bacterial communities, requiring further exploration of its impact on BSFL growth and gut microbiota. The results showed that feeding FW fermented for different durations (0-10 d) slightly affected the BSFL yield. Feeding FW fermented for 8 d, characterized by a lower pH and higher biodiversity, resulted in a slight increase in larval biomass (222 mg/larvae). Nearly all groups harvested the peak larval biomass after 10 day's bioconversion. The fermentation significantly altered the microbial community of FW, with an increase in the abundance of unclassified_f_Clostridiaceae and a decrease in Lactobacillus abundance. As bioconversion progressed, intricate and mutualistic microbial interactions likely occurred between the BSFL gut and FW substrate, restructuring each other's microbial community. Specifically, the abundance of unclassified_f_Clostridiaceae increased in the BSFL gut, while its abundance in the initial larval gut was extremely low (<1 %). Despite the substrate microbial changes and interactions, a stable core gut microbiota was identified across all BSFL samples, primarily composed of nine genera dominated by Enterococcus and Klebsiella. This core gut microbiome may play a crucial role in facilitating the adaptation of BSFL to various environmental conditions and maintaining efficient FW bioconversion. These findings enhance our understanding of the role of BSFL gut microbiota in FW bioconversion.

Comparative life cycle assessment of LFP and NCM batteries including the secondary use and different recycling technologies.

Lithium iron phosphate (LFP) batteries and lithium nickel cobalt manganese oxide (NCM) batteries are the most widely used power lithium-ion batteries (LIBs) in electric vehicles (EVs) currently. The future trend is to reuse LIBs retired from EVs for other applications, such as energy storage systems (ESS). However, the environmental performance of LIBs during the entire life cycle, from the cradle to the grave, has not been extensively discussed. In this study, life cycle assessment (LCA) was used to quantify and compare the environmental impacts of LFP and NCM batteries. Apart from the phases of production, the first use in EVs, and recycling, the repurposing of retired LIBs and their secondary use in the ESS were also included in the system boundary. Also, the environmental impacts of various recycling processes were evaluated. The LCA results suggested that the NCM battery had better comprehensive environmental performance than the LFP one but shorter service life over the whole life cycle. In China, the first and secondary use phases contributed most to the environmental impacts with electricity mostly generated from fossil fuels. The LIB production phase was relevant to all assessed impact categories and contributed more than 50% to Abiotic Depletion Potential (ADP elements) particularly. The environmental loads could be mitigated through the recovery of metals and other materials. And, hydrometallurgy was recommended for recycling waste LIBs by better environmental advantages than pyrometallurgy and direct physical recycling. Sensitivity analysis revealed that by optimizing the charge-discharge efficiency of LIBs, particularly LFP batteries, all environmental burdens could be considerably decreased. Therefore, improving the electrochemical performance of LIBs and increasing the use proportion of clean energy were crucial to reduce the environmental impacts over their entire life cycle.

Unveiling the recycling characteristics and trends of spent lithium-ion battery: a scientometric study.

The recycling of spent lithium-ion batteries (LIBs) is both essential to sustainable resource utilization and environmental conservation. While spent batteries possess a resource value, they pose an environmental hazard at the same time. Since the start of development to recycle spent LIBs in 1990s, important contributions have been made and a number of achievements have been accomplished by scholars globally. Therefore, it is valuable to summarize the developments on spent LIB recycling and to analyze the characteristics and trends comprehensively. A review of the progress in this field will provide guidance for future development. In this study, recycling characteristics and developing trends including the research foundation, milestone, research hotspot, key technologies, and emerging trends were identified based on visual scientometric analysis followed by a discussion on future research directions in this area. For the analysis, 1041 publications in English were collected, summarized, and categorized. The distribution of scientific publications on spent LIB recycling from 1995 to 2020 displayed an increasing trend in numbers. China made the biggest contribution with 528 publications and basically cooperated with all other countries. The research fields with the highest contributions were "engineering", "chemistry", and "environmental science and technology". The keywords recovery, lithium ion battery, and cobalt appeared in high frequency. "Metal value" was identified as the most frequently used keyword which began to burst in 2005 and ended in 2013.