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With the global population on the rise, an escalating interest exists in environmentally sustainable and friendly protein sources. Insects have emerged as multifaceted resources, viewed not only as potential food items, but also as sources of traditional medicines and proteins. This study utilized response surface methodology (RSM) to ascertain the optimal extraction conditions for proteins from Musca domestica used in toad feeding, denoted as MDPs-T. The yield of MDPs-T was elevated to 18.3% ± 0.2% under these optimized conditions. Subsequently, the particle size, ζ-potentials, and structures of MDPs-T were analyzed and compared with the proteins derived from Musca domestica fed on a normal diet (MDPs-ND). This comparative analysis utilized a range of advanced techniques, involving UV spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), high-performance gel permeation chromatography (HPGPC), and scanning electron microscopy (SEM). The outcomes have revealed a marginal disparity in the physical and chemical properties between MDPs-T and MDPs-ND. Derosination led to a reduction in the particle size of the MDPs by 10.98% to 62.81%. MDPs-T exhibited a higher proportion of low-molecular-weight components relative to MDPs-ND. Additionally, in a comparative analysis of amino acids, MDPs-T displayed a greater abundance of essential and total amino acids relative to MDPs-ND. Consequently, MDPs-T holds potential as a valuable food supplement for human consumption or as a nutrient-rich feed supplement for animals. [ABSTRACT FROM AUTHOR]

Abstract: A Hamiltonian‐based methodology is presented to study the fracture behaviors of the thermo‐viscoelastic materials based on the Laplace transform. The governing equations and associated boundary conditions are rebuilt in a Hamiltonian form by using the symplectic mathematics in the frequency domain (s‐domain). The fundamental unknown vector composed of both displacements and stresses variables is expanded in terms of the symplectic eigensolutions. The corresponding unknown coefficients of the symplectic series are determined from the outer boundary conditions. Thus, the main unknowns are obtained and transformed into the time domain (t‐domain). The fracture parameters including stress intensity factors (SIFs) and J‐integrals are derived simultaneously. Numerical examples as well as convergence studies are given and are found to be in good agreement with the ANSYS results. A parametric study of thermo‐viscoelastic parameters is included also. [ABSTRACT FROM AUTHOR]

• Purification of flavonoids from Carex meyeriana Kunth was first optimized. • Five flavonoids and 5-Caffeoylquinic acid were identified from the purified sample. • Purification enriched flavonoids and enlarged the bioactivities. Analytic hierarchy process (AHP) combined with response surface methodology (RSM) was used to optimize the purification processes of the crude flavonoids of Carex meyeriana Kunth (CMK). The bioactivities of flavonoids were evaluated in terms of antioxidant and antimicrobial activities. The weighted coefficients of comprehensive scoring method on AHP included recovery, purity, and decolorization rate. The optimal results were as follows: the sample concentration was 3.04 mg/mL, the ethanol concentration was 70.33 %, pH was 2.93, the elution velocity was 2.95 Bv/h, and the comprehensive score was 75.52 ± 0.53 % (n = 3). The purified flavonoids of CMK (PFCMK) were compared with a reference substance through ultra high-performance liquid chromatography and ultraviolet spectra. Results of composition analyses were as follows: (−)−gallocatechin, 5−Caffeoylquinic acid, (−)−naringin, myricetin, luteolin, and isorhamnetin. The IC 50 values of 2,2–dIphenyl–1-picrylhydrazyl (0.034 mg/mL), hydroxyl radical method (0.643 mg/mL), and reducing power (0.025 mg/mL) showed that PFCMK had strong antioxidant activity. The minimum inhibitory concentrations on Bacillus pumilus, Bacillus subtilis, and Escherichia coli were 1.75, 1.75, and 0.875 mg/mL, respectively. PFCMK can be prepared as an antioxidant and antimicrobial for natural pharmaceutical, cosmetic products, and other industrial products. [ABSTRACT FROM AUTHOR]

• Crop height explained the most variability in maize AGB estimation of V6 stage. • EVI and VARI were selected as the most important narrowband VIs at the R1 stage. • mSR 705 , Vi opt , SRPI, REIP-LI, NDI, Maccioni were important VIs at the R3 stage. • XGBoost model outperformed stepwise and RF regression model in maize AGB estimation. • UAV-based hyperspectral imagery has some advantages for AGB estimation. Monitoring the aboveground biomass (AGB) of maize is essential for improving site-specific nutrient management and predicting yield to ensure food safety. A low-altitude unmanned aerial vehicle (UAV) was employed to acquire hyperspectral imagery of the maize canopy at three growth stages (V6, R1, R3) to estimate the maize AGB. Five maize nitrogen (N) rate experiments were conducted in Lishu County, Jilin Province, Northeastern China, to create different biomass conditions. Combined with crop height data obtained from the field measurements, 30 narrowband vegetation indices (VIs) were extracted using surface reflectance data from the hyperspectral imagery. Stepwise regression, random forest (RF) regression and XGBoost regression models were used to predict the fresh and dry AGB of the 2019 growth season. The study revealed that (1) crop height explained the most variability (60–70%) in the maize dry and fresh AGB estimation of the V6 growth stage, while different VIs exhibited various importance for AGB estimation at other maize growth stages; (2) XGBoost regression models demonstrated high prediction accuracy in both fresh and dry AGB estimation, compared with stepwise regression and RF models. (3) XGBoost models also presented high prediction accuracy at each single-growth stage and the whole-growth stage, with the highest accuracy for the dry AGB at V6 growth stage (R2 = 0.81, RMSE = 0.27 t/ha). This study demonstrated the capability of UAV-based hyperspectral imagery for estimating maize AGB at the field scale, which can be used to assist precision agriculture. [ABSTRACT FROM AUTHOR]