Prediction of Aphid Infestation by Numbers of Overwintering Soybean Aphid Eggs

Aphis glycines Matsumura is a rampant insect pest on cultivated soybeans in Jilin Province. Prediction of its occurrence and infesting tendency is an important basis for effective control. Issues related with the application of overwintering egg numbers to predict the occurrence of soybean aphid were studied in this paper. The ratio of winter host numbers to summer host numbers and overwintering egg quantity in different areas of Jilin Province were compared. Based on data about overwintering egg quantities in winter hosts, Rhamnus davaricus, aphid numbers in early and pre-peak infestation stage from 1961 to 1981 in Gongzhuling district and aphid infestation level in Siping district, the relationship between overwintering egg quantity, and aphid number were analyzed. A prediction equation for forecasting aphid quantity and aphid infestation level by the overwintering egg quantity in Gongzhuling district was proposed.Originating text in Chinese.Citation: Cheng, Ruilu, Wang, Suyun, Bao, Xiangzhi, Xu, Enpei, Xie, Weimin. (1984). Prediction of Aphid Infestation by Numbers of Overwintering Soybean Aphid Eggs. Journal of Jilin Agricultural Sciences, 34(1), 56-61

Improving the Solubility and Digestibility of Potato Protein with an Online Ultrasound-Assisted PH Shifting Treatment at Medium Temperature

Ultrasonic (US) treatment was combined with pH shifting (pHS) and mild thermal (40 °C) (T40) treatment (US/T40/pHS) to improve the solubility of potato protein. The effects of the ultrasonication frequency, ultrasonication time, and incorporation sequence on the solubility of potato protein were investigated. The results showed that online US/T40/pHS treatment resulted in higher solubility of potato protein and enhanced free amino group release during in vitro digestion. The solubility of potato protein treated with online US/T40/pHS at a mono-frequency of 40 kHz for 15 min increased by 1.73 times compared with the control (p < 0.05). The digestibility rate increased by 16.0% and 30.8% during gastric and intestinal digestion, respectively, compared with the control (p < 0.05). It was demonstrated that online US/T40/pHS treatment significantly changed the secondary and tertiary structures of potato protein according to the results of circular dichroism and internal fluorescence. SDS-PAGE, particle size, and atomic force microscopy (AFM) showed that structural changes led to the formation of large soluble aggregates. The results suggested that the improvement in the solubility and digestibility of potato protein treated with online US/T40/pHS may be due to the formation of large soluble aggregates, which are more hydrophilic and sensitive to digestive enzymes

Cooperative Navigation Algorithm of Extended Kalman Filter Based on Combined Observation for AUVs

The navigation and positioning of multi-autonomous underwater vehicles (AUVs) in the complex and variable marine environment is a significant and much-needed area of attention, especially considering the fact that cooperative navigation technology is the essential method for multiple AUVs to solve positioning problems. When the extended Kalman filter (EKF) is applied for underwater cooperative localization, the outliers in the sensor observations cause unknown errors in the measurement system due to deep-sea environmental factors, which are difficult to calibrate and cause a significant reduction in the co-location accuracy of AUVs, and can even cause problems with a divergence of estimation error. In this paper, we proposed a cooperative navigation method of the EKF algorithm based on the combined observation of multiple AUVs. Firstly, the corresponding cooperative navigation model is established, and the corresponding measurement model is designed. Then, the EKF model based on combined observation is designed and constructed, and the unknown error is eliminated by introducing a previously measured value. Finally, simulation tests and lake experiments are designed to verify the effectiveness of the algorithm. The results indicate that the EKF algorithm based on combined observation can approximately eliminate errors and improve the accuracy of cooperative localization when the unknown measurement error cannot be calibrated by common EKF methods. The effect of state estimation is improved, and the accuracy of co-location can be effectively improved to avoid serious declines in—and divergence of—estimation accuracy

Numerical Simulation of Low-Permeability Reservoirs with considering the Dynamic Boundary Layer Effect

Surface active components, salt component, and polar molecules in the fluid may adsorb on the solid surface and form the boundary layer during low-speed flow in a porous medium, which will influence the flowing law in the porous medium. Previous studies on flowing in low-permeability reservoirs mainly focus on the effects of the threshold pressure gradient. But few of them have considered the time-varying effect of the boundary layer thickness in solving the numerical simulation. The correlation among the boundary layer thickness and pressure gradient was established by regressing the experimental data of boundary thickness versus pressure. On this basis, the mathematical model of oil-water two-phase flow which involves influence of the boundary layer was constructed, and the comparative analysis of the development effect is performed. Results demonstrated that the boundary layer thickness is sensitive to the throat radius and pressure gradient, and the boundary layer thickness decreases dynamically with the increase of pressure gradient. The displacement velocity and accumulative oil production with boundary layer effect decrease when comparing with that without the boundary layer effect. Meanwhile, the boundary layer accelerates the breakthrough of water. With the reduction of production pressure difference, the difference between accumulative oil production with and without the boundary layer effect increases, which indicate that the dynamic effect of the boundary layer is intensified

Electric property evidences of carbonification of organic matters in marine shales and its geologic significance: A case study of the Lower Cambrian Qiongzhusi shale in the southern Sichuan Basin

Searching for some reliable evidences that can verify the carbonification of organic matters in marine shales is a major scientific issue in selecting shale gas fairways in old strata. To this end, based on core, logging and testing data, the electric property of two organic-rich shale layers in the Lower Cambrian Qiongzhusi Fm. and the Lower Silurian Longmaxi Fm. in the southern Sichuan Basin was compared to examine the carbonification signs of organic matters in the Qiongzhusi shale and its influence on gas occurrence in the shales. The following conclusions were reached: (1) the electric property experiment shows that the Qiongzhusi shale in the study area has had carbonification of organic matters. The low resistivity of dry samples from this highly mature organic-rich shale and ultra-low resistivity on downhole logs can be used to directly judge the degree of organic matter carbonification and the quality of source rocks; (2) in the Changning area, the Qiongzhusi shale shows low resistivity of dry samples and low to ultra-low resistivity on logs, indicating that organic matters are seriously carbonized, while in the Weiyuan area, the Qiongzhusi shale shows a basically normal resistivity on log curves, indicating its degree of graphitization between the Longmaxi Fm. and Qiongzhusi Fm. in the Changning area; (3) shale with medium-to-high resistivity is remarkably better than that with ultra-low resistivity in terms of gas generation potential, matrix porosity and gas adsorption capacity; (4) industrial gas flow has been tested in the organic shales with medium-to-high resistivity in the Jianwei–Weiyuan–Tongnan area in the north, where the Qiongzhusi shale is a favorable shale gas exploration target

Analysis of factors associated with delayed diagnosis and treatment of testicular torsion in 1005 cases from Chongqing city, China: a cross-sectional study

Abstract This study aimed to investigate the clinical and social factors of delayed treatment for testicular torsion (TT) and to explore the risk factors of testicular excision in China. The clinical data of 1005 patients with TT who were admitted to 48 medical institutions in Chongqing city (China) from January 2012 to December 2021 were retrospectively analyzed. It was revealed that the misdiagnosis rates of non-senior (junior and middle) grade doctors and senior doctors were 25.1% and 9.6%, respectively. The proportion of TT patients who received timely treatment (within 6 h after onset of symptoms) was 23.8%. The results of the multivariable logistic regression analysis indicated that absent cremasteric reflex was a protective factor for delayed surgery of more than 6 h from onset of symptoms to surgery. Misdiagnosis, consultation with a non-urologist as the first consultant doctor, absence blood flow in color Doppler ultrasound, negative high-riding testis findings, the presence of fever, and non-manual detorsion were identified as risk factors associated with delayed surgery (more than 6 h from the onset of symptoms) for TT. Furthermore, misdiagnosis, non-urologist first-consultant doctor, absent blood flow in DUS, non-manual detorsion, fever, degree of cord twisting > 180, and the initial diagnosis in tertiary hospitals were risk factors for orchidectomy. Having TT on the right side, and the presence of nausea and vomiting were identified as protective factors for orchidectomy. Technical training in the diagnosis and treatment of TT should be extended to primary hospitals and doctors to significantly improve their accuracy in managing this condition

Agrobacterium tumefaciens mediated transformation of marine microalgae Schizochytrium

Ocean Public Welfare Scientific Research Special Appropriation Project [200805041]Schizochytrium was a known docosahexaenoic acid producing marine microalgae. In this study, we have developed a novel transformation approach of Schizochytrium using the Agrobacterium tumefaciens (A. tumefaciens) binary vector system. After co-cultivation of Schizochytrium protoplasts with A. tumefaciens harboring pCAMBIA2301 containing the neomycin phosphotransferase II (NPT II) gene as the selectable marker which confers resistance to G418, the Schizochytrium transformants were successfully obtained on the G418-containing plates. The integration and expression of the transgenes were confirmed by PCR analysis and GUS activity assay. To further validate the transformation system, pCAMBIA2301-EGFP containing the egfp gene was introduced into Schizochytrium. The following results demonstrated that the exogenous egfp gene has been successfully incorporated into the genome of Schizochytrium. In addition, the introduced egfp gene expressed efficiently according to the Western blot and fluorescence assay results. More importantly, the majority of the transformants displayed similar biomass and fatty acid production comparing with the wild type strain. Our results demonstrated that exogenous genes could be expressed efficiently in transgenic Schizochytrium, suggesting that genetically engineered Schizochytrium could be explored by this system. (C) 2011 Elsevier GmbH. All rights reserved

Inverse Relations of PM2.5 and O3 in Air Compound Pollution between Cold and Hot Seasons over an Urban Area of East China

Abstract: By analyzing the data of urban air pollutant measurements from 2013 to 2015 in Nanjing, East China, we found that the correlation coefficients between major atmospheric compound pollutants PM2.5 and O3 were respectively 0.40 in hot season (June, July and August) and −0.16 in cold season (December, January and February) with both passing the confidence level of 99%. This provides evidence for the inverse relations of ambient PM2.5 and O3 between cold and hot seasons in an urban area of East China. To understand the interaction of PM2.5 and O3 in air compound pollution, the underlying mechanisms on the inversion relations between cold and hot seasons were investigated from the seasonal variations in atmospheric oxidation and radiative forcing of PM2.5 based on three-year environmental and meteorological data. The analyses showed that the augmentation of atmospheric oxidation could strengthen the production of secondary particles with the contribution up to 26.76% to ambient PM2.5 levels. High O3 concentrations in a strong oxidative air condition during hot season promoted the formation of secondary particles, which could result in a positive correlation between PM2.5 and O3 in hot season. In cold season with weak atmospheric oxidation, the enhanced PM2.5 levels suppressed surface solar radiation, which could weaken O3 production for decreasing ambient O3 level with the low diurnal peaks. Under the high PM2.5 level exceeding 115 μg·m−3, the surface O3 concentration dropped to 12.7 μg·m−3 at noon with a significant inhibitory effect, leading to a negative correlation between PM2.5 and O3 in cold season. This observational study revealed the interaction of PM2.5 and O3 in air compound pollution for understanding the seasonal change of atmospheric environment

CRISPR-Cas9-mediated chicken prmt5 gene knockout and its critical role in interferon regulation

ABSTRACT: Protein arginine methyltransferase 5 (PRMT5), a type II arginine methyltransferase, controls arginine dimethylation of a variety of substrates. While many papers have reported the function of mammalian PRMT5, it remains unclear how PRMT5 functions in chicken cells. In this study, we found that chicken (ch) PRMT5 is widely expressed in a variety of chicken tissues and is distributed in both the cytoplasm and the nucleus. Ectopic expression of chPRMT5 significantly suppresses chIFN-β activation induced by chMDA5. In addition, a prmt5 gene-deficient DF-1 cell line was constructed using CRISPR/Cas9. In comparison with the wild-type cells, the prmt5−/− DF-1 cells displays normal morphology and maintain proliferative capacity. Luciferase reporter assay and overexpression showed that prmt5−/− DF-1 cells had increased IFN-β production. With identified chicken PRMT5 and CRISPR/Cas9 knockout performed in DF-1 cells, we uncovered a functional link of chPRMT5 in suppression of IFN-β production and interferon-stimulated gene expression