Effects of eugenol on physicochemical properties of sturgeon skin collagen-chitosan composite membrane.

In this study, a series of collagen-chitosan-eugenol (CO-CS-Eu) flow-casting composite films were prepared using collagen from sturgeon skin, chitosan, and eugenol. The physicochemical properties, mechanical properties, microstructure, as well as antioxidant and antimicrobial activities of the composite membranes were investigated by various characterization techniques. The findings revealed that the inclusion of eugenol augmented the thickness of the film, darkened its color, reduced the transparency, and enhanced the ultraviolet light-blocking capabilities, with the physicochemical properties of the CO-CS-0.25%Eu film being notably favorable. Eugenol generates increasingly intricate matrices that disperse within the system, thereby modifying the optical properties of the material. Furthermore, the tensile strength of the film decreased from 70.97 to 20.32 MPa, indicating that eugenol enhances the fluidity and ductility of the film. Added eugenol also exhibited structural impact by loosening the film cross-section and decreasing its density. The Fourier transform infrared spectroscopy results revealed the occurrence of several intermolecular interactions among collagen, chitosan, and eugenol. Moreover, the incorporation of eugenol bolstered the antioxidant and antimicrobial capabilities of the composite film. This is primarily attributed to the abundant phenolic/hydroxyl groups present in eugenol, which can react with free radicals by forming phenoxy groups and neutralizing hydroxyl groups. Consequently, inclusion of eugenol substantially enhances the freshness retention performance of the composite film. PRACTICAL APPLICATION: ● The CO-CS-Eu film utilizes collagen from sturgeon skin, improving the use of sturgeon resources.● Different concentrations of eugenol altered its synergistic effect with chitosan.● The CO-CS-Eu film is composed of natural products with safe and edible properties.

Assessment of Blood Volume in Liposuction Fluids Using Colorimetry.

OBJECTIVE: The possibility of using a color contrast method to evaluate blood loss during liposuction was assessed. A color chart of blood-lipid content associated with different blood volumes was developed. METHODS: Three color cards with different concentrations of blood were developed based on clinical parameters. The color cards were used to evaluate the volume of blood present in liposuction solutions obtained from 60 clinical liposuction patients. The red blood cell count also was evaluated for each patient. The data obtained using each evaluation method were compared and statistically analyzed to determine the most accurate calculation formula. RESULTS: The red blood cell counts were compared to the color card results. The paired t test results for the calculated values for the 3:1, 2:1, and 1:1 color cards and the red blood cell count values were comparable (44.3 ± 22.1 ml vs. 53.6 ± 25.0 ml, t = 10.5; 45.4 ± 19.0 ml vs. 55.2 ± 20.7 ml, t = 18.1; 41.9 ± 25.6 ml vs. 52.8 ± 28.3 ml, t = 14.0). The P values were < 0.05, and the difference between the two groups was statistically significant. The average standard error of the mean was 0.90, 0.54, and 0.77, respectively. Sixty samples were evaluated in a scatter diagram using the two detection methods. Trend analysis revealed that the two results demonstrated a linear increase (y = 5.6 + 1.1x), R2 = 0.989, indicating that the two inspection methods were highly correlated with only small errors. CONCLUSION: The colorimetric card protocol developed in this study could quickly, accurately, and conveniently calculate blood volumes in liposuction fluids, which has considerable clinical significance. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Ozone Degradation of Prometryn in Ruditapes philippinarum: Response Surface Methodology Optimization and Toxicity Assessment.

ABSTRACT: This study optimized the method for ozone (O3) degradation of prometryn in the clam Ruditapes philippinarum and evaluated toxicity changes during ozone degradation. The gas chromatography method for the detection of prometryn was appropriately improved. The linear range was 5 to 500 ng/mL, with a correlation coefficient of 0.9964. The addition concentration of prometryn was 0.025 to 0.100 mg/kg, the recovery was 77.97 to 85.00%, the relative standard deviation (n = 6) was 2.36 to 7.86%, and the limit of detection was 0.3 µg/kg. Using the central composite design in two experiments, ozone as gas and ozone dissolved in water, the effect of degradation rate was studied on three variables: ozone concentration, temperature, and exposure time. Ozone as gas and ozone dissolved in water have the same degradation effect on prometryn. The O3 concentration was 4.2 mg/L, the temperature was 40°C, the exposure time was 10 min, and the maximum degradation rate was 89.94 and 89.69% for the two experiments, respectively. In addition, the toxicity of ozone degradation products was evaluated using buffalo rat liver cells. After ozone treatment for 30 min, the toxicity of the ozone degradation products was reduced to 52.15% compared with that of prometryn itself. The toxicity of the ozone degradation products increased slightly when the ozonation time was prolonged; the toxicity at 180 min was greater than that of the parent compound prometryn. Overall, the application of ozone degradation of pesticide residues is a promising new technology. This study determined better degradation conditions for prometryn in R. philippinarum and also provided a theoretical basis for the widespread use of ozone technology in the future.

Degradation of prometryn in Ruditapes philippinarum using ozonation: Influencing factors, degradation mechanism, pathway and toxicity assessment.

In recent years, prometryn was utilized as watergrass remover in the aquaculture industry, resulting in the accumulated residual in the aquatic products. The present study focuses on the ozone degradation of prometryn in the Ruditapes philippinarum. The ozone concentration in water increased along with the injection time (60min). The contents of hydroxyl (·OH) and superoxide (O2·-) radicals increased along with the ozone injection time. The effects of temperature, pH, prometryn initial concentration and ozone concentration on the removal efficiency of prometryn were evaluated. The maximum removal efficiency of 86.12% was obtained under the conditions of pH 7, prometryn initial concentration 0.05 mg/kg and the ozone concentration 4.2 mg/L at 28 °C for 30 min. Ion chromatography (IC) and Fourier transform infrared (FT-IR) spectroscopy results show that the S and N atoms in the outer layer of the triazine ring during the prometryn degradation process were oxidized and removed. A total of 30 intermediate compounds were identified using the gas chromatography-mass spectrometry (GC-MS) method. Combined with the IC and FT-IR results, three possible degradation pathways of prometryn were proposed. The prometryn was finally degraded into some small molecules with reduced toxicity by 63.16% for 120 min ozonization treatment. Overall, our work provides a novel approach for prometryn degradation in Ruditapes philippinarum, which can be extended for removing the residues of agricultural and veterinary drugs in other aquatic products.

DOA Estimation for Underwater Wideband Weak Targets Based on Coherent Signal Subspace and Compressed Sensing.

Direction of arrival (DOA) estimation is the basis for underwater target localization and tracking using towed line array sonar devices. A method of DOA estimation for underwater wideband weak targets based on coherent signal subspace (CSS) processing and compressed sensing (CS) theory is proposed. Under the CSS processing framework, wideband frequency focusing is accompanied by a two-sided correlation transformation, allowing the DOA of underwater wideband targets to be estimated based on the spatial sparsity of the targets and the compressed sensing reconstruction algorithm. Through analysis and processing of simulation data and marine trial data, it is shown that this method can accomplish the DOA estimation of underwater wideband weak targets. Results also show that this method can considerably improve the spatial spectrum of weak target signals, enhancing the ability to detect them. It can solve the problems of low directional resolution and unreliable weak-target detection in traditional beamforming technology. Compared with the conventional minimum variance distortionless response beamformers (MVDR), this method has many advantages, such as higher directional resolution, wider detection range, fewer required snapshots and more accurate detection for weak targets.

Insecticide toxicity and synergism by enzyme inhibitors in 18 species of pest insect and natural enemies in crucifer vegetable crops.

The toxicities of three enzyme inhibitors and their synergistic effects on four insecticides were studied by using the dry film method on field populations of 18 species of insects collected in Jianxin and Shanjie, China, from 2003 to 2005. Meanwhile, the inhibitory effects of these enzyme inhibitors on the activities of acetylcholinesterases (AChE), carboxyesterases (CarE) and glutathione-S-transferases (GST), in vivo, were also studied. In general, triphenyl phosphate (TPP) and diethyl maleate (DEM) showed low toxicities to six herbivorous pest insects, four ladybirds and eight parasitoids. Piperonyl butoxide (PB) exhibited low toxicities to the herbivorous pest insects and ladybirds, but high toxicities to the eight parasitoids. The tolerance to the insecticides in 11 pest insects and natural enemies was mainly associated with the tolerance to PB. PB showed the highest synergism on methamidophos, fenvalerate, fipronil and avermectin in nine species of pest insects and natural enemies. In general, TPP and DEM showed significant synergisms to these four insecticides in four parasitoid species. However, in contrast to their effects on the parasitoids, the synergistic effects of TPP and DEM on the four insecticides by TPP and DEM against four pest insects and one ladybird varied depending on the insect species and enzyme inhibitor. Activity of AChE, CarE or GST could be strongly inhibited, in vivo, by PB, TPP or DEM, depending on the insect species and enzyme inhibitors. From the results obtained in this study, mixed-function oxidase (MFO) was thought to play the most critical role in insect tolerances to the tested insecticides in the field. Low competition existed in the evolution of insecticide resistance in the field populations of parasitoids, as compared with herbivorous pest insects and ladybirds. Possible causes of the high synergistic effects of PB on the four classes of insecticides, based on multiattack on the activity of CarE, GST or AChE in the insect species, are also discussed.