Determination of seawater COD spectra using double-loop contraction and sorted frog optimization.

This study develops a novel double-loop contraction and value sorting selection-based shrinkage frog-leaping algorithm (double-contractive cognitive random field [DC-CRF]) to mitigate the interference of complex salts and ions in seawater on the ultraviolet-visible (UV-Vis) absorbance spectra for chemical oxygen demand (COD) quantification. The key innovations of DC-CRF are introducing variable importance evaluation via value to guide wavelength selection and accelerate convergence; a double-loop structure integrating random frog (RF) leaping and contraction attenuation to dynamically balance convergence speed and efficiency. Utilizing seawater samples from Jiaozhou Bay, DC-CRF-partial least squares regression (PLSR) reduced the input variables by 97.

Simultaneous detection of trace adulterants in food based on multi-molecular infrared (MM-IR) spectroscopy.

Simultaneously rapid detection of trace adulterants in the complex systems of food without extraction is considered highly challenging. Herein, a high-throughput and rapid methodology, multi-molecular infrared (MM-IR) spectroscopy was developed for simultaneous detection of multiple trace adulterants in food. Flour was applied to demonstrate the capabilities of MM-IR with spatial resolution, spectral qualitative and quantitative analysis.

Stochastic determination of the spatial variation of potentially pathogenic bacteria communities in a large subtropical river.

Understanding the composition and assembly mechanism of waterborne pathogen is essential for preventing the pathogenic infection and protecting the human health. Here, based on 16S rRNA sequencing, we investigated the composition and spatial variation of potentially pathogenic bacteria from different sections of the Pearl River, the most important source of water for human in Southern China. The results showed that the potential pathogen communities consisted of 6 phyla and 64 genera, covering 11 categories of potential pathogens mainly involving animal parasites or symbionts (AniP), human pathogens all (HumPA), and intracellular parasites (IntCelP).

Integral characterization of normal and alopecic hair at different degeneration stages by in-situ visible and chemical imaging.

Direct exploration to differences between normal hair (NH) and alopecic hair (AH) at different degeneration stages is still lacking. To reveal compositional and structural variation of AH with reference to NH internally and externally, infrared spectroscopic imaging combined with scanning electron microscopy was applied to investigate integral changes of hair chemical profiles and surface texture structures, and infrared macro-fingerprinting analysis revealed detailed chemical compositions of NH and AH. Results showed that AH had excessive irregular laminated structures compared to NH, leading to a lower weight bearing capacity.

Integrated recognition and quantitative detection of starch in surimi by infrared spectroscopy and spectroscopic imaging.

Surimi products have become increasingly-consumed food with prominent characteristics of high nutrition and convenience and its supply falls short of demand. However, due to exhausted fishery resource in recent years, surimi adulteration, such as addition of plant proteins, starch and other animal origin meat, is becoming serious, so recognition of these exogenous substances has become an urgent issue. In this study, Fourier transform infrared spectroscopy (FT-IR) combined with infrared spectroscopic imaging could distinguish heterogeneity in surimi qualitatively and quantitatively and obtain integral chemical images so that spatial distribution of each component in surimi could be visually displayed, thus a rapid recognition method and a prediction model were developed.