Alterations in the surface properties of sea spray aerosols introduced by the presence of sterols

SSCI-VIDE+CARE+CGOInternational audiencehe mixed stearic acid (SA)/sterol systems were used as sea spray aerosol mimics to get more insights into the al-terations in surface properties of aerosols induced by sterols. By means of surface pressure (π)–area(A) isotherms and polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS), the effect ofcholesterol (chol), stigmasterol (stig) and ergosterol (erg) on the lateral packing and chain conformation of SAmonolayer was explored. The fact that the excess areas of mixing of the mixed monolayers exhibit significant devi-ations from ideally mixedfilm proves that, the sterols are miscible withSA throughout all the monolayer composi-tions and surface pressures examined. The lift-off areas inπ–A isotherms were found to increase with increasingmole fraction of sterols, indicating that expulsive interactions exist between SA and sterols, which are more pro-nounced when the mole fraction of sterols is 0.7. In addition, the peak intensities ofνa(CH2)andνs(CH2)inIRRASspectra decrease with increasing sterols levels, which is consistent with ourfindings in theπ–A isotherms, thatthe addition of sterols leads to a looser chain packing in SA monolayer. The proportion ofgauchedefects in SA mono-layer induced by the sterols follows the order cholesterol stigmast ergosterol at a certain sterol level, as reflected by the decreasing peak intensities fνa(CH2)andνs(CH2). Consequently, the sterols generally give riseto considerable expanding effects on SA monolayer, which are particularly pronounced for stigmasterol and ergos-terol, suggesting that the additional alkyl side chains and double bonds of thesterols play a role on disordering SAmonolayer. The present study is likely to shed light on many boundary processes take place at the interface ofSSAs, in particular, transport processes of water and trace gases across the interfac

Editing Large Language Models: Problems, Methods, and Opportunities

Despite the ability to train capable LLMs, the methodology for maintaining their relevancy and rectifying errors remains elusive. To this end, the past few years have witnessed a surge in techniques for editing LLMs, the objective of which is to efficiently alter the behavior of LLMs within a specific domain without negatively impacting performance across other inputs. This paper embarks on a deep exploration of the problems, methods, and opportunities related to model editing for LLMs. In particular, we provide an exhaustive overview of the task definition and challenges associated with model editing, along with an in-depth empirical analysis of the most progressive methods currently at our disposal. We also build a new benchmark dataset to facilitate a more robust evaluation and pinpoint enduring issues intrinsic to existing techniques. Our objective is to provide valuable insights into the effectiveness and feasibility of each editing technique, thereby assisting the community in making informed decisions on the selection of the most appropriate method for a specific task or context. Code and datasets are available at https://github.com/zjunlp/EasyEdit.Comment: EMNLP 2023. Updated with new experiment

Fiber‐specific regulation of lignin biosynthesis improves biomass quality in Populus

Lignin is a major component of cell wall biomass and decisively affects biomass utilisation. Engineering of lignin biosynthesis is extensively studied, while lignin modification often causes growth defects. We developed a strategy for cell‐type‐specific modification of lignin to achieve improvements in cell wall property without growth penalty. We targeted a lignin‐related transcription factor, LTF1, for modification of lignin biosynthesis. LTF1 can be engineered to a nonphosphorylation form which is introduced into Populus under the control of either a vessel‐specific or fibre‐specific promoter. The transgenics with lignin suppression in vessels showed severe dwarfism and thin‐walled vessels, while the transgenics with lignin suppression in fibres displayed vigorous growth with normal vessels under phytotron, glasshouse and field conditions. In‐depth lignin structural analyses revealed that such cell‐type‐specific downregulation of lignin biosynthesis led to the alteration of overall lignin composition in xylem tissues reflecting the population of distinctive lignin polymers produced in vessel and fibre cells. This study demonstrates that fibre‐specific suppression of lignin biosynthesis resulted in the improvement of wood biomass quality and saccharification efficiency and presents an effective strategy to precisely regulate lignin biosynthesis with desired growth performance

Day-ahead optimization of integrated electricity and thermal system combining multiple types of demand response strategies and situation awareness technology

Under the dual pressure of energy shortage and environmental pollution, relying only on increasing the installed capacity of units and line transmission capacity cannot cope with the conflict between the growth of power demand and the difficulty of grid expansion in the long run. Demand response conducts users to change their energy consumption habits through system-issued electricity prices or incentives, so that the demand of the load side can be adjusted flexibly, which can further enhance the consumption of wind power and improve system economics. Based on the background of diversified energy use, this paper proposes a day-ahead optimal scheduling strategy for integrated electricity and thermal system considering multiple types of demand response. Firstly, the dispatch framework of integrated electricity and thermal system with the situation awareness technology is constructed to address uncertainties of Renewable Energy Sources, thus helping system mitigate uncertain risks. Secondly, the demand response mechanism of power system and regional thermal inertia of thermal system are modeled, respectively, to uncover the principles of load regulation of different energy systems; Then, a day-ahead optimal scheduling model for the integrated thermal and electricity system is developed, and the consumption evaluation index is integrated to indicate energy utilization efficiency; Finally, a combined electric-heat system model with 39-node grid and 6-node heat network is developed, and the positive effects of considering multiple types of demand response and situation awareness technology on promoting the consumption of renewable energy and improving the energy efficiency of the system are verified through the case study