Large Language Models for Automated Open-domain Scientific Hypotheses Discovery

Hypothetical induction is recognized as the main reasoning type when scientists make observations about the world and try to propose hypotheses to explain those observations. Past research on hypothetical induction has a limited setting that (1) the observation annotations of the dataset are not raw web corpus but are manually selected sentences (resulting in a close-domain setting); and (2) the ground truth hypotheses annotations are mostly commonsense knowledge, making the task less challenging. In this work, we propose the first NLP dataset for social science academic hypotheses discovery, consisting of 50 recent papers published in top social science journals. Raw web corpora that are necessary for developing hypotheses in the published papers are also collected in the dataset, with the final goal of creating a system that automatically generates valid, novel, and helpful (to human researchers) hypotheses, given only a pile of raw web corpora. The new dataset can tackle the previous problems because it requires to (1) use raw web corpora as observations; and (2) propose hypotheses even new to humanity. A multi-module framework is developed for the task, as well as three different feedback mechanisms that empirically show performance gain over the base framework. Finally, our framework exhibits high performance in terms of both GPT-4 based evaluation and social science expert evaluation

Microarray‑based analysis of COL11A1 and TWIST1 as important differentially‑expressed pathogenic genes between left and right‑sided colon cancer.

Colonic cancer has become a main reason of mortality associated with cancer; however, left and right‑sided colonic cancer have diverse outcomes in terms of epidemiological, histological, clinical parameters and prognosis. We aimed to examine the discrepancies between these two types of colon cancers to identify potential therapeutic targets. In the present study, three gene expression profiles (GSE44076, GSE31595, GSE26906) from Gene Expression Omnibus (GEO) database were downloaded and further analyzed. A PPI (protein‑protein interaction) network of the differentially‑expressed genes (DEGs) of GSE44076 between tumor and normal was established with the Search Tool for the Retrieval of Interacting Genes database. Then, the DEGs of these two colon cancers (left, right) samples were identified. Subsequently, the intersection of DEGs of left and right‑sided colon cancer samples obtained from three databases, and DEGs of tumor and normal samples were analyzed. Collagen type XI α1 chain (COL11A1), Twist family bHLH transcription factor 1 (TWIST1), insulin‑like 5 and chromogranin A were upregulated proteins, while 3β‑hydroxysteroid dehydrogenase was downregulated protein in right colon cancer than in left‑sided tumor samples. Through further experimental verification, we revealed that COL11A1 and TWIST1 were significantly upregulated at the mRNA and protein levels within right‑sided colon cancer compared with in left‑sided colon cancer samples (P<0.05), consistent with bioinformatical analysis. Furthermore, a positive correlation between COL11A1 and TWIST1 protein expression was observed (P<0.0276). Collectively, our data showed that COL11A1 and TWIST1 may be potential prognostic indicators and molecular targets for the treatment of right‑sided colon cancer

The impact of onshore wind power projects on ecological corridors and landscape connectivity in Shanxi, China

The wind power industry has developed rapidly in China, but the effect of wind power projects on the ecosystem is far from being clearly understood. The objective of this study is to evaluate the negative impact of wind power plants on the ecosystem. In this research, least-cost distance and least-cost path models were employed to establish potential ecological corridors based on the resistance at the site of the wind power projects––which is located in the ecological function area in Qinyuan, South Shanxi Province, China. The landscape connectivity was evaluated using a set of connectivity indices. In addition, the impact on the corridor patency, length, and the connectivity between ecological corridors were analyzed. The results showed that the wind power projects could not only significantly increase the migration resistance that hampers the formation of ecological corridors of the species at the landscape scale, but also had an obvious cutting effect on the landscape––resulting in an increase in the length of the ecological corridors and a decrease in corridor patency and landscape connectivity. There was also a positive relationship between the increase in length and the distance between the source patches. In addition, the connectivity was enhanced with the increase in distance threshold. This study evaluated the ecological impact of onshore wind power projects at the landscape level, filling the gap in research on landscape ecology, especially in the protected area with key ecological function. Meanwhile, the results are beneficial to guide the location selection for wind power projects and minimize their negative impact on the key ecological corridors

The role of protein contents in promoting wastewater phosphorus and bioenergy recovery during anaerobic digestion

Proteins present in domestic and industrial wastewater, yet their role in nutrient and energy recovery during anaerobic digestion (AD) has not been well understood. This study aimed to examine the impact of feedwater protein content on the calcium phosphate (CaP) precipitation under a low supersaturation condition and the methane production in an AD process. Four 1.0 L upflow anaerobic sludge blanket (UASB) reactors were fed with the synthetic feeds with different protein contents. The results showed that the amino acid degradation caused the pH elevation, triggering the CaP precipitation. A 25% bovine serum albumin (BSA) content in the feedwater helped shape a superior microbial community that contributed to a methanisation rate of 82.7%. The high prevalence of the phylum Synergistetes and the methanogen Methanosaeta suggested that methane was mainly produced through the acetate utilization.</p

Enhancing methane production and organic loading capacity from high solid-content wastewater in modified granular activated carbon (GAC)-amended up-flow anaerobic sludge blanket (UASB)

Anaerobic digestion of high solid-content wastewater is hindered by high organic loading rates (OLRs). Granular activated carbon (GAC) was reported to promote direct interspecies electron transfer (DIET) and enhance reactor performance. In this study, three up-flow anaerobic sludge blanket (UASB) reactors were supplied with GAC in different locations: bottom (R1), top (R2), and bottom+top (R3). The performances of three reactors at different OLRs treating high solid-content wastewater were evaluated. At a low OLR, the highest methane yield (74 ± 4 %, g CH4-COD/g TCOD) was detected when GAC was supplied at top of the UASB (R2). When a high OLR was applied, the UASB supplemented with GAC at both bottom and top (R3) achieved the highest methane yield (66 ± 2 %, g CH4-COD/g TCOD), whereas the UASB supplemented with GAC at the top (R2) failed. Further studies on spatial distributions of sludge stability, specific methanogenic activities (SMAs), and microbial communities demonstrated the different impacts of GAC location on reactor performance and sludge characteristics under different OLRs. This study highlights the significance of considering organic loading capacity treating high solid-content wastewater when choosing GAC-based UASB systems.</p

The role of protein contents in promoting wastewater phosphorus and bioenergy recovery during anaerobic digestion

Proteins present in domestic and industrial wastewater, yet their role in nutrient and energy recovery during anaerobic digestion (AD) has not been well understood. This study aimed to examine the impact of feedwater protein content on the calcium phosphate (CaP) precipitation under a low supersaturation condition and the methane production in an AD process. Four 1.0 L upflow anaerobic sludge blanket (UASB) reactors were fed with the synthetic feeds with different protein contents. The results showed that the amino acid degradation caused the pH elevation, triggering the CaP precipitation. A 25% bovine serum albumin (BSA) content in the feedwater helped shape a superior microbial community that contributed to a methanisation rate of 82.7%. The high prevalence of the phylum Synergistetes and the methanogen Methanosaeta suggested that methane was mainly produced through the acetate utilization.</p

Age and productivity : a sector perspective

In this study, we investigate the influence of sector size on productivity profile using a cross-country panel data. We theorize that different demands of the labour force necessitated by the different sectors results in varying productivity profiles. The findings that an expansion of the service industry will likely flatten the overall productivity profile suggest a relatively flat profile of the service industry. In contrast, an expansion of the agriculture sector may boost overall productivity of younger age groups. We also find that high income countries and ageing countries tend to have a later peak in productivity compared to low and low middle income and non-ageing countries respectively. The least productive sector is also likely to have more influence on the overall productivity profile. However, the investigations only analyse and identify broader global trends, providing underlying fundamentals for future empirical studies of the dynamics within sectors.Bachelor of Art

Effluent recirculation weakens the hydrolysis of high-solid content feeds in upflow anaerobic sludge blanket reactors

Effluent recirculation in an upflow anaerobic sludge blanket (UASB) reactor is a commonly used strategy to improve both mixing and upflow velocity of the reactor. This study aimed to assess the impact of effluent recirculation on methane production of UASB reactors treating substrates of different solid contents. Two 2.0 L UASB reactors were operated for 219 d under mesophilic conditions. When the UASB reactors were fed with a high-solid content substrate, effluent recirculation led to significantly reduced methanisation rate (from 47.9% without recirculation to 25.5% with recirculation) and hydrolysis efficiency of particulate organic matter (from 45.5% without recirculation to 22% with recirculation). In comparison to the high-solid content substrate, a low-solid content substrate led to an increase in methanisation rate for both UASB reactors with and without effluent recirculation, but the difference in methane production for the two reactors reduced significantly. Results demonstrated that the lower methane production in the presence of effluent recirculation arose from the inefficient hydrolysis of particulate organic matter, which was mitigated when the reactors were fed with a low-solid content substrate. Turbulence due to effluent recirculation enhanced biomass transport but limited the accessibility of adsorption sites on particulate matter. An insufficient attachment between microorganisms/enzymes and particles could have lowered the hydrolysis efficiency of particulate organic matter.</p

Impact of feedwater protein contents on calcium phosphate mineralization in anaerobic digesters

Calcium phosphate (CaP) mineralization and accumulation in anaerobic digesters represent an attractive approach to recovery phosphorus (P) from wastewater. Previous studies demonstrated that under certain anaerobic digestion conditions, favorable localized environment can be developed to facilitate CaP granule growth. However, factors that trigger the CaP nucleation in anaerobic reactors have not been elucidated. In this study, to examine the driving forces in the microenvironment for the CaP nucleation, two laboratory upflow anaerobic sludge blanket (UASB) reactors fed with two types of synthetic wastewater were operated under mesophilic conditions. The feed of one reactor (G reactor) had glucose as the sole carbon source, and the feed of the other reactor (G+B reactor) had glucose (60% chemical oxygen demand (COD)) and bovine serum albumin (BSA, 40% COD) as the combined carbon sources. The results showed that P and Ca removals were only observed in the G+B reactor. The main difference between the two reactors was the elevated pH in the G+B reactor, which may be attributed to the degradation of amino acids. The elevated pH caused the deprotonation of the negatively charged functional groups in the sludge, creating available active surfaces for Ca2+ complexation. The high availability of OH- and the enriched Ca in the G+B reactor built a favorable microenvironment to overcome the activation energy barriers hindering the CaP nucleation. The stabilized CaP mineralization largely depended on the well-established microbial community, where the efficient hydrogenotrophic methanogens and syntrophic acetogens may maintain a stabilized pH environment to prevent the dissociation of CaP minerals.</p