HRoT: Hybrid prompt strategy and Retrieval of Thought for Table-Text Hybrid Question Answering

Answering numerical questions over hybrid contents from the given tables and text(TextTableQA) is a challenging task. Recently, Large Language Models (LLMs) have gained significant attention in the NLP community. With the emergence of large language models, In-Context Learning and Chain-of-Thought prompting have become two particularly popular research topics in this field. In this paper, we introduce a new prompting strategy called Hybrid prompt strategy and Retrieval of Thought for TextTableQA. Through In-Context Learning, we prompt the model to develop the ability of retrieval thinking when dealing with hybrid data. Our method achieves superior performance compared to the fully-supervised SOTA on the MultiHiertt dataset in the few-shot setting

MMHQA-ICL: Multimodal In-context Learning for Hybrid Question Answering over Text, Tables and Images

In the real world, knowledge often exists in a multimodal and heterogeneous form. Addressing the task of question answering with hybrid data types, including text, tables, and images, is a challenging task (MMHQA). Recently, with the rise of large language models (LLM), in-context learning (ICL) has become the most popular way to solve QA problems. We propose MMHQA-ICL framework for addressing this problems, which includes stronger heterogeneous data retriever and an image caption module. Most importantly, we propose a Type-specific In-context Learning Strategy for MMHQA, enabling LLMs to leverage their powerful performance in this task. We are the first to use end-to-end LLM prompting method for this task. Experimental results demonstrate that our framework outperforms all baselines and methods trained on the full dataset, achieving state-of-the-art results under the few-shot setting on the MultimodalQA dataset

TableQAKit: A Comprehensive and Practical Toolkit for Table-based Question Answering

Table-based question answering (TableQA) is an important task in natural language processing, which requires comprehending tables and employing various reasoning ways to answer the questions. This paper introduces TableQAKit, the first comprehensive toolkit designed specifically for TableQA. The toolkit designs a unified platform that includes plentiful TableQA datasets and integrates popular methods of this task as well as large language models (LLMs). Users can add their datasets and methods according to the friendly interface. Also, pleasantly surprised using the modules in this toolkit achieves new SOTA on some datasets. Finally, \tableqakit{} also provides an LLM-based TableQA Benchmark for evaluating the role of LLMs in TableQA. TableQAKit is open-source with an interactive interface that includes visual operations, and comprehensive data for ease of use.Comment: Work in progres

Microbially mediated nitrate-reducing Fe(II) oxidation: Quantification of chemodenitrification and biological reactions

Redox reactions between iron and nitrogen drive the global biogeochemical cycles of these two elements and, concomitantly, change the fate of nutrients in and the mineralogy of the cycles. The microbially mediated NO3--reducing Fe(II) oxidation process (NRFO) plays a key role in Fe/N interactions under neutral-anoxic conditions. Microbially mediated NRFO was considered a biological process, yet recently it has been documented that chemical mechanisms are also at play. However, the relative contributions of biological processes and chemical processes to Fe(II) oxidation remain largely unquantified owing to the co-occurrence of the reactions. Herein, the kinetics and secondary minerals of microbially mediated NRFO by Pseudogulbenkiania sp. strain 2002 and Acidovorax sp. strain BoFeN1 were investigated with acetate as electron donor unless otherwise stated. The results of Cells + NO3- suggested the two strains could biologically reduce NO3- to NO3-/NOx/N2O/N-2 and concomitantly oxidize acetate and result in cell growth. Fe(II) oxidation and NO3- reduction occurred simultaneously in the presence of Fe(II) (Cells + Fe(II) + NO3-). For strain BoFeN1, the presence of Fe(II) slightly enhanced the NO3- reduction, acetate consumption, and cell growth, all of which were substantially retarded by Fe(II) for strain 2002. When compared with the microbial nitrite reduction, the relatively higher rate of chemical reaction between NO2- and dissolved Fe(II) confirmed the occurrence of chemodenitrification in the microbially mediated NRFO processes. After 5 days' incubation, no green rust was observed, and lepidocrocite, goethite, and magnetite were observed with the Cells + Fe(II) + NO3- treatment, but only goethite was found with the Fe(II) + NO2-. The spectra for the EPSs + Fe(II) treatment suggested that the oxidized c-Cyts in the EPSs could oxidize Fe(II), which show the theoretical capability of taking electrons from Fe(II) into the cells via c-Cyts. A brief model was established by combining the verified reactions of (1) biological reduction of NO3- to NO2-/NOx/N2O/N-2, (2) Fe(II) oxidation by NO2-, and (3) Fe(II) oxidation by c-Cyts in EPSs. Based on the model, the rate constant of Fe(II) oxidation by c-Cyts in EPSs was derived. For nitrite reduction, the relative contribution of biological processes to the nitrite reduction was higher than that of chemodenitrification. For Fe(II) oxidation, the relative contribution of the chemical process via nitrite to Fe(II) oxidation was higher than that of biological processes. These findings provide a quantitative interpretation of the chemodenitrification and biological reactions in the microbially mediated NRFO processes, which could assist the mechanistic understanding of the global biogeochemical cycles of iron and nitrogen in subsurface environments. (C) 2018 Elsevier Ltd. All rights reserved

Biological and chemical processes of microbially mediated nitrate-reducing Fe(II) oxidation by Pseudogulbenkiania sp strain 2002

In the microbially mediated nitrate-reducing Fe(II) oxidation system, it is recognized that chemical oxidation of Fe(II) by nitrite, which is a bioreduction intermediate of nitrate, can occur under anoxic conditions (chemo-denitrification), but it is still difficult to quantitatively evaluate the contributions of biological Fe(II) oxidation and chemodenitrification. Here, nitrate reduction coupled with Fe(II) oxidation by a suggested lithoautotro phic nitrate-reducing Fe(II)-oxidizing bacterium, Pseudogulbenkiania sp. strain 2002, was investigated in PIPES buffered medium without any organic cosubstrate through reaction kinetics, nitrogen isotope fractionation, and secondary mineral characterization. Substantial Fe(II) oxidation was observed in the presence of cells and nitrate, and nitrite (0.59 mM) was able to quickly oxidize Fe(II). Stored carbon in strain 2002 harvested during pre-incubation can serve as carbon source for nitrate reduction. Furthermore, the N isotopic composition (delta N-15) of N2O in Cell + NO3- + Fe(II) was much more negative than those in Cell + NO3-/ NO2-, Cell + NO2- + Fe (II), and NO2- + Fe(II), implying that Fe(II) affects N fractionation associated with the reduction of nitrate to nitrite. Goethite was formed in Fe(II)+ NO2-, while lepidocrocite was the main mineral phase in Cell + Fe(II) + NO3-. The morphology and cell-mineral interactions determined by electron microscopy showed that secondary minerals were formed outside of cells in Cell + NO2- + Fe(II), while cell encrustation was observed in the periplasmic space of cells in Cell + NO3- + Fe(II). The secondary minerals present in the different treatments further illustrated the co-occurrence of biological, chemical, and coupling processes in the microbially mediated nitrate-reducing Fe(II) oxidation system. This study highlights the involvements of the biological Fe(II) oxidation and chemical Fe(II) oxidation by nitrite in microbially mediated nitrate-reducing Fe(II) oxidation

Quantifying Redox Dynamics of c-Type Cytochromes in a Living Cell Suspension of Dissimilatory Metal-reducing Bacteria

To quickly and accurately quantify the redox dynamics of c-type cytochromes (c-Cyts) in a living cell suspension, diffuse transmission UV/visible (DT-UV/Vis) and normal UV/Vis spectroscopy were used to record spectra of c-Cyts in living Shewanella oneidensis MR-1 bacteria. DT-UV/Vis showed a higher absorbance of c-Cyts and lower background compared with normal UV/Vis, because interference from cell surface scattering was removed. The extinction coefficients of oxidized c-Cyts (410 nm) and reduced c-Cyts (419 and 552 nm) were observed. Using this method and the obtained c-Cyts extinction coefficients, the redox transformation kinetics of c-Cyts under anoxic conditions were successfully examined in the presence of various electron acceptors, including 9,10-anthraquinone-2,6-disulfonic acid, Cr(VI), Fe(Ill) citrate and oxygen. Therefore, the in situ spectral analysis of outer-membrane proteins of intact cells using DT-UV/Vis spectroscopy appears a promising method for investigating microbial metal reduction processes in living cell systems