{2-[2-(Carb­oxy­meth­oxy)­phen­oxy]acetato}[2,2′-(o-phenyl­enedi­oxy)diacetic acid]sodium 4,4′-bipyridine hemisolvate monohydrate

In the title compound, [Na(C10H9O6)(C10H10O6)]·0.5C10H8N2·H2O, the Na atom is eight-coordinated in an distorted dicapped-octa­hedral geometry by eight O atoms from a 2-(2-carb­oxy­meth­oxy­phen­oxy)acetate (o-BDOAH) anion and a 2,2′-(o-phenyl­enedi­oxy)diacetic acid (o-BDOAH2) mol­ecule. The uncoordinated 4,4′-bipyridine mol­ecule is arranged around an inversion center and exhibits rotational disorder. A three-dimensional supra­molecular network is built up in the crystal through O—H⋯O and O—H⋯N hydrogen bonds between the uncoordinated water mol­ecule, the uncoordinated 4,4′-bipyridine mol­ecule and the sodium complex mol­ecule

Systematic Analysis of Head-to-Head Gene Organization: Evolutionary Conservation and Potential Biological Relevance

Several “head-to-head” (or “bidirectional”) gene pairs have been studied in individual experiments, but genome-wide analysis of this gene organization, especially in terms of transcriptional correlation and functional association, is still insufficient. We conducted a systematic investigation of head-to-head gene organization focusing on structural features, evolutionary conservation, expression correlation and functional association. Of the present 1,262, 1,071, and 491 head-to-head pairs identified in human, mouse, and rat genomes, respectively, pairs with 1– to 400–base pair distance between transcription start sites form the majority (62.36%, 64.15%, and 55.19% for human, mouse, and rat, respectively) of each dataset, and the largest group is always the one with a transcription start site distance of 101 to 200 base pairs. The phylogenetic analysis among Fugu, chicken, and human indicates a negative selection on the separation of head-to-head genes across vertebrate evolution, and thus the ancestral existence of this gene organization. The expression analysis shows that most of the human head-to-head genes are significantly correlated, and the correlation could be positive, negative, or alternative depending on the experimental conditions. Finally, head-to-head genes statistically tend to perform similar functions, and gene pairs associated with the significant cofunctions seem to have stronger expression correlations. The findings indicate that the head-to-head gene organization is ancient and conserved, which subjects functionally related genes to correlated transcriptional regulation and thus provides an exquisite mechanism of transcriptional regulation based on gene organization. These results have significantly expanded the knowledge about head-to-head gene organization. Supplementary materials for this study are available at http://www.scbit.org/h2h

A Case-Based Reasoning Framework for Adaptive Prompting in Cross-Domain Text-to-SQL

Recent advancements in Large Language Models (LLMs), such as Codex, ChatGPT and GPT-4 have significantly impacted the AI community, including Text-to-SQL tasks. Some evaluations and analyses on LLMs show their potential to generate SQL queries but they point out poorly designed prompts (e.g. simplistic construction or random sampling) limit LLMs' performance and may cause unnecessary or irrelevant outputs. To address these issues, we propose CBR-ApSQL, a Case-Based Reasoning (CBR)-based framework combined with GPT-3.5 for precise control over case-relevant and case-irrelevant knowledge in Text-to-SQL tasks. We design adaptive prompts for flexibly adjusting inputs for GPT-3.5, which involves (1) adaptively retrieving cases according to the question intention by de-semantizing the input question, and (2) an adaptive fallback mechanism to ensure the informativeness of the prompt, as well as the relevance between cases and the prompt. In the de-semanticization phase, we designed Semantic Domain Relevance Evaluator(SDRE), combined with Poincar\'e detector(mining implicit semantics in hyperbolic space), TextAlign(discovering explicit matches), and Positector (part-of-speech detector). SDRE semantically and syntactically generates in-context exemplar annotations for the new case. On the three cross-domain datasets, our framework outperforms the state-of-the-art(SOTA) model in execution accuracy by 3.7\%, 2.5\%, and 8.2\%, respectively

5-(4-Chloro­phen­yl)-1H-tetra­zole

The two independent mol­ecules of the title compound, C7H5ClN4, both lie on a twofold rotation axis that passes through the centroids of the five- and six-membered rings and the attached Cl C atom. One molecule is nearly planar [dihedral angle between rings = 0.22 (6)°], whereas the other is significantly twisted [dihedral angle = 17.38 (6)°]. In the crystal, adjacent mol­ecules are linked by N—H⋯N hydrogen bonds into a chain structure

The construction of bifunctional fusion xylanolytic enzymes and the prediction of optimum reaction conditions for the enzyme activity

Four chimeric xylanolytic enzymes were formed by fusion of a thermally stable xylanase XynCDBFV either to the N-terminus or C-terminus of a thermally stable acetylxylan esterase AxeS20E, with or without a Gly-rich flexible linker (S2). The three-dimensional (3D) structures of the chimeric enzymes were predicted using the I-TASSER server, and the results indicated that the structures of Axe-S2-Xyn and Xyn-S2-Axe were more similar to the native structures than were those of Axe-Xyn and Xyn-Axe. Axe-S2-Xyn and Xyn-S2-Axe were expressed in Escherichia coli and purified by means of affinity chromatography. Response surface modeling (RSM), combined with central composite design (CCD) and regression analysis, was then employed to optimize the xylanase activities of the chimeric enzymes. Under the optimal conditions, Xyn-S2-Axe had greater hydrolytic activities on natural xylans and rice straw than did the parental enzymes. These results suggested that the chimeric enzyme Xyn-S2-Axe could be effective at hydrolyzing xylan in biomass and that it has potential to be used in a range of biotechnological applications