A novel computer vision based method for PDF academic literature structure understanding

The PDF format plays a crucial role in the field of electronic academic literature publishing, but due to its complicated technical rules, PDF cannot be directly read by machines, which has caused a lot of inconvenience to the research work on academic literature. This poster proposes a computer vision-based PDF document structure understanding method. This method maps visual objects and text objects in PDF academic papers and obtains geometric and text attributes of content objects, supplemented by a heuristic algorithm. The algorithm performs type classification on the content object to obtain the physical structure and logical structure of the PDF document. This method overcomes the shortcomings of other PDF analysis methods that require a large number of artificial feature construction or large-scale corpus training, difficult to identify formula tables, and success-fully constructs a structure understanding and full-text extraction of ACM's collections

Analysis of Construction Cost and Investment Planning Using Time Series Data

Construction costs and investment planning are the decisions made by construction managers and financial managers. Investment in construction materials, labor, and other miscellaneous should consider their huge costs. For these reasons, this research focused on analyzing construction costs from the point of adopting multivariate cost prediction models in predicting construction cost index (CCI) and other independent variables from September 2021 to December 2022. The United States was selected as the focal country for the study because of its size and influence. Specifically, we used the Statistical Package for Social Sciences (SPSS) software and R-programming applications to forecast the elected variables based on the literature review. These forecasted values were compared to the CCI using Pearson correlations to assess influencing factors. The results indicated that the ARIMA model is the best forecasting model since it has the highest model-fit correlation. Additionally, the number of building permits issued, the consumer price index, the amount of money supply in the country, the producer price index, and the import price index are the influencing factors of investments decisions in short to medium ranges. This result provides insights to managers and cost planners in determining the best model to adopt. The improved accuracies of the influencing factors will help to enhance the control, competitiveness, and capability of futuristic decision-making of the cost of materials and labor in the construction industry

A Historical Sedimentary Record of Mercury in a Shallow Eutrophic Lake: Impacts of Human Activities and Climate Change

Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the 1960s, the concentration of Hg began to increase gradually, and showed a higher concentration of contamination in the western half of the lake region than in the eastern half of the lake region due to all kinds of centralized human-input sources. The influences of anthropogenic factors and hydrological change are revealed by analyzing correlations between Hg and heavy metals (Fe, Co, Cr, Cu, Mn, Pb, and Zn), stable carbon and nitrogen isotopes (δ13C and δ15N), nutrients, particle sizes, and meteorological factors. The results show that Hg pollution intensified after the 1960s, mainly due to hydrological change, rapid regional development and urbanization, and the proliferation of anthropogenic Hg sources. Furthermore, the temperature, wind speed, and evaporation are found to interactively influence the environmental behaviors and environmental fate of Hg

Molecular Level Comparison of Water Extractives of Maple and Oak with Negative and Positive Ion ESI FT-ICR Mass Spectrometry

Soluble extractives in wood function to protect living trees from destructive agents and also contribute to wood color and fragrance. Some extractive components have biological activities with medical applications. They also play important roles in wood processing and related applications. To increase the knowledge of wood chemistry, maple and oak were extracted by water. Ultraviolet/visible (UV/vis) spectroscopy indicated the presence of a phenolic compound, resorcinol, in maple extractives having higher molecular mass and more aromatic components than oak extractives. Negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS) identified thousands of formulas in the two samples in the m/z range of 200 to 800. They mainly fall into the lignin-like, carbohydrate-like, and tannin-like compound categories. The top 25 peaks (ie, formulas) with the highest relative magnitude in negative ESI represented nearly 50% of the summed total spectral magnitude of all formulas assigned in the maple and oak extractives. Furthermore, the base peak (ie, most abundant peak) accounted for about 14% of the total abundance in each wood sample. Literature comparisons identified 17 of 20 formulas in the top five peaks of the four spectra as specific bioactive compounds in trees and other plants, implying the potential to explore utilization of maple and oak extractives for functional and medicinal applications. The various profiling of the top 25 peaks from the two samples also suggested the possible application of FT-ICR-MS for detecting chemical markers useful in profiling and identification of wood types and sources

Ecological risk assessment of fifty pharmaceuticals and personal care products (PPCPs) in Chinese surface waters: a proposed multiple-level system

Interest in the risks posed by trace concentrations of pharmaceuticals and personal care products (PPCPs) in surface waters is increasing, particularly with regard to potential effects of long-term, low-dose exposures of aquatic organisms. In most cases, the actual studies on PPCPs were risk assessments at screening-level, and accurate estimates were scarce. In this study, exposure and ecotoxicity data of 50 PPCPs were collected based on our previous studies, and a multiple-level environmental risk assessment was performed. The 50 selected PPCPs are likely to be frequently detected in surface waters of China, with concentrations ranging from the ng L−1 to the low-g L−1, and the risk quotients based on median concentrations ranged from 2046 for nonylphenol to 0 for phantolide. A semi-probabilistic approach screened 33 PPCPs that posed potential risks to aquatic organisms, among which 15 chemicals (nonylphenol, sulfamethoxazole, di (2-ethylhexyl) phthalate, 17β-ethynyl estradiol, caffeine, tetracycline, 17β-estradiol, estrone, dibutyl phthalate, ibuprofen, carbamazepine, tonalide, galaxolide, triclosan, and bisphenol A) were categorized as priority compounds according to an optimized risk assessment, and then the refined probabilistic risk assessment indicated 12 of them posed low to high risk to aquatic ecosystem, with the maximum risk products ranged from 1.54% to 17.38%. Based on these results, we propose that the optimized risk assessment was appropriate for screening priority contaminants at national scale, and when a more accurate estimation is required, the refined probability risk assessment is useful. The methodology and process might provide reference for other research of chemical evaluation and management for rivers, lakes, and sea waters

Single-nucleotide polymorphisms are associated with cognitive decline at Alzheimer's disease conversion within mild cognitive impairment patients

INTRODUCTION: The growing public threat of Alzheimer's disease (AD) has raised the urgency to quantify the degree of cognitive decline during the conversion process of mild cognitive impairment (MCI) to AD and its underlying genetic pathway. The aim of this article was to test genetic common variants associated with accelerated cognitive decline after the conversion of MCI to AD. METHODS: In 583 subjects with MCI enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI; ADNI-1, ADNI-Go, and ADNI-2), 245 MCI participants converted to AD at follow-up. We tested the interaction effects between individual single-nucleotide polymorphisms and AD diagnosis trajectory on the longitudinal Alzheimer's Disease Assessment Scale-Cognition scores. RESULTS: Our findings reveal six genes, including BDH1, ST6GAL1, RAB20, PDS5B, ADARB2, and SPSB1, which are directly or indirectly related to MCI conversion to AD. DISCUSSION: This genome-wide association study sheds light on a genetic mechanism of longitudinal cognitive changes during the transition period from MCI to AD

A New Multi-Objective Comprehensive Optimization Model for Homogeneous Slope Reinforced by Anti-Slide Piles: Insights from Numerical Simulation

AbstractLandslides have posed a huge threat to the ecological environment and human society all over the world. As the most conventional reinforcement method, anti-slide piles are widely used in the reinforcement of slopes. Currently, more and more attention has been paid to the low-cost and high-efficiency optimal design of anti-slide piles. However, limitations in the method of the optimization design for slopes reinforced with piles still exist. In this paper, a new multi-objective comprehensive optimization method was proposed for the optimization of the slope reinforced with anti-slide piles. The factor of safety, internal force, and deflection of piles were selected as the optimization indexes, and the optimization index weight was determined by integrating the subjective and objective weights. The influence of pile locations, pile lengths, and pile spacings on the reinforcement effect of a homogeneous slope was analyzed via the numerical simulation. Through the simulation case analysis, the proposed model had achieved good effects on the optimization design of anti-slide piles, which could effectively reduce the engineering costs. The optimization results showed that the best reinforcement effect for the homogeneous slope could be obtained when the anti-slide piles with the critical pile length and small pile spacing were located in the middle of the slope. This provides a new solution for the optimization design of other types of complex slopes and has broad application prospects

Binding of dicamba to soluble and bound extracellular polymeric substances (EPS) from aerobic activated sludge: A fluorescence quenching study

Binding of dicamba to soluble EPS (SEPS) and bound EPS (BEPS) from aerobic activated sludge was investigated using fluorescence spectroscopy. Two protein-like fluorescence peaks (peak A with Ex/Em = 225 nm/342-344 nm and peak B with Ex/Em = 275/340-344 nm) were identified in SEPS and BEPS. Humic-like fluorescence peak C (Ex/Em = 270-275 nm/450-460 nm) was only found in BEPS. Fluorescence of the peaks A and B for SEPS and peak A for BEPS were markedly quenched by dicamba at all temperatures whereas fluorescence of peaks B and C for BEPS was quenched only at 298 K. A dynamic process dominated the fluorescence quenching of peak A of both SEPS and BEPS. Fluorescence quenching of peak B and C was governed a static process. The effective quenching constants (log K-a) were 4.725-5.293 for protein-like fluorophores of SEPS and 4.23-5.190 for protein-like fluorophores of BEPS, respectively. Log K-a for humic-like substances was 3.85. Generally, SEPS had greater binding capacity for dicamba than BEPS, and protein-like substances bound dicamba more strongly than humic-like substances. Binding of dicamba to SEPS and BEPS was spontaneous and exothermic. Electrostatic force and hydrophobic interaction forces play a crucial role in binding of dicamba to EPS. (C) 2010 Elsevier Inc. All rights reserved.

Predicted no-effect concentration (PNEC) and assessment of risk for the fungicide, triadimefon based on reproductive fitness of aquatic organisms

Triadimefon, a broad-spectrum, systemic fungicide used to protect agricultural crops is popular in China. However, sub-lethal effects of triadimefon on aquatic organisms remained poorly understood, and its risks to aquatic organisms were unclear. In the current study, thresholds for chronic toxicity to five aquatic organisms were determined and a PNEC based on reproductive fitness of nine aquatic organisms was derived through use of a species sensitivity distribution (SSD). NOECs, based on reproduction or inhabitation of growth, for Oryzias latipes, Daphnia magna, Brachionus calyciflorus, Heterocypris incongruens and Soirodela polyrhiza were 5, 25, 80, 320 and 500 μg L−1, respectively, and the final PNEC derived was 3.66 μg L−1. A screening-level hazard assessment of surface water based on both measured environment concentrations (ND∼5.22 μg L−1) in 3 lakes, 2 reservoirs and 1 river and predicted environment concentrations (0.36–65 μg L−1) in a simulated river and pond, identified unacceptable hazard to aquatic organisms posed by triadimefon, with maximum hazard quotients (HQs) of 1.43 and 17.8, respectively. Potential deleterious effects and hazards or risks of exposure of aquatic organisms from current patterns of use of triadimefon in surface water if of concern. Since HQs were relatively small and the benefits large, it is suggested that mitigations be applied to allow use while minimizing potential for adverse effects on aquatic organisms

Long-term wetland biomonitoring highlights the differential impact of land use on macroinvertebrate diversity in Dongting Lake in China

Freshwater wetlands have experienced disproportionate biodiversity loss due to environmental change. The lack of long-term biological data limits our understanding of wetland biodiversity dynamics and principal drivers. Here, we combine aquatic biomonitoring with satellite-derived imagery and spatial-explicit analysis to assess the changes in macroinvertebrate diversity and driving factors from 1988 to 2017 in Dongting Lake, China. The results revealed declining macroinvertebrate alpha diversity (species richness and functional redundancy) but increased beta diversity (taxonomic and functional dissimilarity). An increase in nutrients due to changes in land-use intensity in the surrounding terrestrial ecosystem was the primary mechanism for the losses of species and functional groups. Alpha diversity changes were most influenced by land-use changes in adjacent land areas 1.5 kilometers from the sampling sites, while beta diversity was affected within 50 meters. Our results highlight a need for attenuating land-use effects by establishing protected buffer areas to protect biodiversity in the future