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Circular economy-based investments remain modest when compared to sustainability investments. Private investors interested in the circular economy currently have limited choices. To advance the transition to a circular economy, understanding private funding motivation, options, and outcomes are research directions that need to be pursued. Interdisciplinary researchers from environmental sustainability, ecological economics, and finance communities are urged to explore private financing options for the circular economy. 

Mass spectrometry (MS)‐based top‐down proteomics (TDP) analysis of histone proteoforms provides critical information about combinatorial post‐translational modifications (PTMs), which is vital for pursuing a better understanding of epigenetic regulation of gene expression. It requires high‐resolution separations of histone proteoforms before MS and tandem MS (MS/MS) analysis. In this work, for the first time, we combined SDS‐PAGE‐based protein fractionation (passively eluting proteins from polyacrylamide gels as intact species for mass spectrometry, PEPPI‐MS) with capillary zone electrophoresis (CZE)‐MS/MS for high‐resolution characterization of histone proteoforms. We systematically studied the histone proteoform extraction from SDS‐PAGE gel and follow‐up cleanup as well as CZE‐MS/MS, to determine an optimal procedure. The optimal procedure showed reproducible and high‐resolution separation and characterization of histone proteoforms. SDS‐PAGE separated histone proteins (H1, H2, H3, and H4) based on their molecular weight and CZE provided additional separations of proteoforms of each histone protein based on their electrophoretic mobility, which was affected by PTMs, for example, acetylation and phosphorylation. Using the technique, we identified over 200 histone proteoforms from a commercial calf thymus histone sample with good reproducibility. The orthogonal and high‐resolution separations of SDS‐PAGE and CZE made our technique attractive for the delineation of histone proteoforms extracted from complex biological systems.

 

Mass spectrometry (MS)-based top-down characterization of integral membrane proteins (IMPs) is crucial for understanding their functions in biological processes. However, it is technically challenging due to their low solubility in typical MS-compatible buffers. In this work, for the first time, we developed an efficient capillary zone electrophoresis (CZE)-tandem MS (MS/MS) method for the top-down proteomics (TDP) of IMPs enriched from mouse brains. Our technique employs a sample buffer containing 30% (v/v) formic acid and 60% (v/v) methanol for solubilizing IMPs and utilizes a separation buffer of 30% (v/v) acetic acid and 30% (v/v) methanol for maintaining the solubility of IMPs during CZE separation. Single-shot CZE-MS/MS identified 51 IMP proteoforms from the mouse brain sample. Coupling size exclusion chromatography (SEC) to CZE-MS/MS enabled the identification of 276 IMP proteoforms from the mouse brain sample containing 1-4 transmembrane domains. This proof-of-concept work demonstrates the high potential of CZE-MS/MS for the large-scale TDP of IMPs. 

Function approximation (FA) has been a critical component in solving large zero-sum games. Yet, little attention has been given towards FA in solving general-sum extensive-form games, despite them being widely regarded as being computationally more challenging than their fully competitive or cooperative counterparts. A key challenge is that for many equilibria in general-sum games, no simple analogue to the state value function used in Markov Decision Processes and zero-sum games exists. In this paper, we propose learning the Enforceable Payoff Frontier (EPF)---a generalization of the state value function for general-sum games. We approximate the optimal Stackelberg extensive-form correlated equilibrium by representing EPFs with neural networks and training them by using appropriate backup operations and loss functions. This is the first method that applies FA to the Stackelberg setting, allowing us to scale to much larger games while still enjoying performance guarantees based on FA error. Additionally, our proposed method guarantees incentive compatibility and is easy to evaluate without having to depend on self-play or approximate best-response oracles.

 

Non-governmental organizations for environmental conservation have a significant interest in monitoring conservation-related media and getting timely updates about infrastructure construction projects as they may cause massive impact to key conservation areas. Such monitoring, however, is difficult and time-consuming. We introduce NewsPanda, a toolkit which automatically detects and analyzes online articles related to environmental conservation and infrastructure construction. We fine-tune a BERT-based model using active learning methods and noise correction algorithms to identify articles that are relevant to conservation and infrastructure construction. For the identified articles, we perform further analysis, extracting keywords and finding potentially related sources. NewsPanda has been successfully deployed by the World Wide Fund for Nature teams in the UK, India, and Nepal since February 2022. It currently monitors over 80,000 websites and 1,074 conservation sites across India and Nepal, saving more than 30 hours of human efforts weekly. We have now scaled it up to cover 60,000 conservation sites globally.

 

Characterization of histone proteoforms with various post‐translational modifications (PTMs) is critical for a better understanding of functions of histone proteoforms in epigenetic control of gene expression. Mass spectrometry (MS)‐based top‐down proteomics (TDP) is a valuable approach for delineating histone proteoforms because it can provide us with a bird's‐eye view of histone proteoforms carrying diverse combinations of PTMs. Here, we present the first example of coupling capillary zone electrophoresis (CZE), ion mobility spectrometry (IMS), and MS for online multi‐dimensional separations of histone proteoforms. Our CZE‐high‐field asymmetric waveform IMS (FAIMS)‐MS/MS platform identified 366 (ProSight PD) and 602 (TopPIC) histone proteoforms from a commercial calf histone sample using a low microgram amount of histone sample as the starting material. CZE‐FAIMS‐MS/MS improved the number of histone proteoform identifications by about 3 folds compared to CZE‐MS/MS alone (without FAIMS). The results indicate that CZE‐FAIMS‐MS/MS could be a useful tool for comprehensive characterization of histone proteoforms with high sensitivity.