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This paper aims to investigate the key points for olive oil total migration test for multilayer laminated films. The samples were made into 1.20 dm2 specimens. The tests of total migration in olive oil were carried out according to the standard GB31604.8—2021. It was found that the results of moisture- sensitive determination for the same material samples were various. The results of olive oil total migration differed greatly between conditioned and unconditioned moisture-sensitive samples. The test results of the volatiles measurement of the specimens also affected the final value of the total migration. Concurrently, the results of the volatiles measurement of the specimens of different multilayer composite films were different. Due to the different materials, the laminate membrane had different adsorption capacity for olive oil. The result determinations were affected by the completeness of olive oil extraction. Therefore, the test results of total migration in olive oil should fully consider the steps of specimen moisture conditioning, volatile matter determination and the number of olive oil extraction to ensure the accuracy of test results.

ObjectiveTo analyze and predict the striking velocity range of stick blunt instruments in different populations, and to provide basic data for the biomechanical analysis of blunt force injuries in forensic identification.MethodsBased on the Photron FASTCAM SA3 high-speed camera, Photron FASTCAM Viewer 4.0 and SPSS 26.0 software, the tester’s maximum striking velocity of stick blunt instruments and related factors were calculated and analyzed, and inputed to the backpropagation （BP） neural network for training. The trained and verified BP neural network was used as the prediction model.ResultsA total of 180 cases were tested and 470 pieces of data were measured. The maximum striking velocity range was 11.30-35.99 m/s. Among them, there were 122 female data, the maximum striking velocity range was 11.63-29.14 m/s; there were 348 male data, the maximum striking velocity range was 20.11-35.99 m/s. The maximum striking velocity of stick blunt instruments increased with the increase of weight and height, but there was no obvious increase trend in the male group; the maximum striking velocity decreased with age, but there was no obvious downward trend in the female group. The maximum striking velocity of stick blunt instruments has no significant correlation with the material and strike posture. The root mean square error （RMSE）, the mean absolute error （MAE） and the coefficient of determination （R2） of the prediction results by using BP neural network were 2.16, 1.63 and 0.92, respectively.ConclusionThe prediction model of BP neural network can meet the demand of predicting the maximum striking velocity of different populations.

ObjectiveTo reconstruct the cases of acceleration craniocerebral injury caused by blunt in forensic cases by finite element method （FEM）, and to study the biomechanical mechanism and quantitative evaluation method of blunt craniocerebral injury.MethodsBased on the established and validated finite element head model of Chinese people, the finite element model of common injury tool was established with reference to practical cases in the forensic identification, and the blunt craniocerebral injury cases were reconstructed by simulation software. The cases were evaluated quantitatively by analyzing the biomechanical parameters such as intracranial pressure, von Mises stress and the maximum principal strain of brain tissue.ResultsIn case 1, when the left temporal parietal was hit with a round wooden stick for the first time, the maximum intracranial pressure was 359 kPa; the maximum von Mises stress of brain tissue was 3.03 kPa at the left temporal parietal; the maximum principal strain of brain tissue was 0.016 at the left temporal parietal. When the right temporal was hit with a square wooden stick for the second time, the maximum intracranial pressure was 890 kPa; the maximum von Mises stress of brain tissue was 14.79 kPa at the bottom of right temporal lobe; the maximum principal strain of brain tissue was 0.103 at the bottom of the right temporal lobe. The linear fractures occurred at the right temporal parietal skull and the right middle cranial fossa. In case 2, when the forehead and left temporal parietal were hit with a round wooden stick, the maximum intracranial pressure was 370 kPa and 1 241 kPa respectively, the maximum von Mises stress of brain tissue was 3.66 kPa and 26.73 kPa respectively at the frontal lobe and left temporal parietal lobe, and the maximum principal strain of brain tissue was 0.021 and 0.116 respectively at the frontal lobe and left temporal parietal lobe. The linear fracture occurred at the left posterior skull of the coronary suture. The damage evaluation indicators of the simulation results of the two cases exceeded their damage threshold, and the predicted craniocerebral injury sites and fractures were basically consistent with the results of the autopsy.ConclusionThe FEM can quantitatively evaluate the degree of blunt craniocerebral injury. The FEM combined with traditional method will become a powerful tool in forensic craniocerebral injury identification and will also become an effective means to realize the visualization of forensic evidence in court.

We researched label symbols and instructions of food contact products in China, expecting to provide technical guidance on label design regulation for manufacters. This paper summarizes the technical specification of food contact product labeling and instructions for use by reviewing domestic and international regulations on food contact product. This study finds that China’s standards do not specify that only products having passed the quality requirements of the national standards for food contact products can be marked with the "food contact" symbol, resulting in poor "Food contact" symbol brand effect. In addition, the standards do not have systematic and comprehensive regulations on the use of the product instructions and precautions. Therefore, this paper proposes to improve the relevant regulations and standards, so that the "food contact" symbol is linked to good quality of the product and brand effect can be strengthened. We also suggest to refine the instructions and precautions for use of regulations and standards, thereby promoting the standardization of the labeling of food contact products and instructions.

A pair of atropisomers secofumitremorgins C (1a) and D (1b), together with fifteen known alkaloids (2-16), were isolated from a saltern-derived fungus Aspergillus fumigatus GXIMD00544. The structures of atropisomers 1a and 1b were elucidated by the detailed spectroscopic data, chemical reaction and quantum chemical calculations. Compounds 1 and 8 displayed antifungal spore germination effects against plant pathogenic fungus associated with sugarcane Fusarium sp. with inhibitory rates of 53% and 77% at the concentration of 100 µM, repectively. Atropisomers 1 also exhibited antifouling potential against Balanus amphitrite larval settlement with an inhibitory rate of 96% at the concentration of 100 µM. [ABSTRACT FROM AUTHOR]

Objective: Established a group of models used to quickly distinguish anti-counterfeit cigarette packaging paper. Methods: The model based on the same color oil on packaging paper from 3 different brands: Yunyan, Yuxi, and Hongtashan. The Fourier Transform infrared spectroscopy （FTIR） spectrum were collected from 116 samples totally by Attenuated Total Reflection （ATR） accessary. 56 spectrum were used to build the models and 20 samples of each brand were used to verification. Spectrum were second derivative processed and spectral ranges were selected as 3 200~2 700, 1 800~1 580, and 801~720 cm-1. Results: Using Mahalanobis distance discriminant method to establish 4 models （3 brands and 1 multiple）, all of the accuracy of models reached to 100%. Conclusion: This is the first time to use the same color oil FTIR spectrum to distinguish real and fake cigarette packaging paper which were highly improve selection efficiency for large number of samples.

Objective To explore the risk factors for asymptomatic deep venous thrombosis (DVT) in patients with acute ischemic stroke and determine the predictive value of risk indicators. Methods Two hundred thirty ⁃ nine acute ischemic stroke patients admitted to Beijing Shijitan Hospital, Capital Medical University from September 2018 to June 2019 met the inclusion criteria. According to the Doppler ultrasound results 7 d after admission, all eligible patients were screened for the presence of asymptomatic DVT. Univariate and multivariate Logistic regression analyses were used to identify risk factors for asymptomatic DVT. The value of risk factors for predicting asymptomatic DVT was analyzed by receiver operating characteristic curve (ROC) analysis. Results Thirty⁃seven (15.48%) patients with acute ischemic stroke had asymptomatic DVT. The multivariate forward Logistic regression analysis showed elevated D ⁃ dimer level on admission was the critical risk factor for asymptomatic DVT (OR = 1.012, 95%CI: 1.011-1.013; P = 0.000). The cut⁃off value for plasma D⁃dimer in diagnosing asymptomatic DVT in the acute ischemic stroke patients was 343 ng/ml (sensitivity = 0.784, specificity = 0.901), and the area under the ROC curve was 0.89 ± 0.03 (95%CI: 0.846-0.929, P = 0.000). Conclusions D⁃dimer is an essential marker of asymptomatic DVT in patients with acute ischemic stroke. Its elevated level is a potential risk factor for asymptomatic DVT.

Sintering deformation is a great hindrance to the development of ceramic components with complex shapes. In this work, single-face coating method has been used to prepare the special shaped Al 2 O 3 components by taking advantage of the difference in shrinkage between substrate and coating. By adjusting the content of SiO 2 in the coating material which consisted of SiO 2 and Al 2 O 3 powder, the sintering deformation of Al 2 O 3 ceramics coated with the above material would be controlled during the sintering process. The sintering behavior of Al 2 O 3 green body with and without single-face coating were studied through visual in-situ tests combined with photographing technology. By comparing the images of specimens under different sintering temperatures (defined this method as the image relative method), the warped deformation and the shrinkage behavior of the above specimens were discussed. Moreover, the relationship between curvature radius and shrinkage rate was deduced. Results indicate that, due to the discrepancy in shrinkage of substrate and coating, the deformation of samples occurred in the heating process. And the shrinkage, the elasticity modulus and the ratio of the sectional coating area to substrate area play a major role in determining the shape of ceramics. The way to fabricate the shape controlled ceramic components by the gradient shrinkage is a novel and effective method, which can be used for the plate and shell products with complex shapes. [ABSTRACT FROM AUTHOR]

In the new era of China’s development for higher vocational college students have new quality development requirements, especially in terms of ideological quality, college students in the new era are required to have patriotic feelings and practical action, correct overall view of world development, and conscious view of global ecological environment protection. At a higher vocational college in Anhui province for two months investigation and study of the topic, through the data analysis found that some problems existing in the college students in the new era of ideological quality development: some college students of level of concern for domestic event and domestic security is not high, and the patriotic practical actions need to be further improved; Some of them have a shallow understanding of the international situation, and the ideological quality of a few college students does not meet the requirements of The times; College students have nearly for ecological environment protection is the lack of action. It puts forward the corresponding countermeasures and Suggestions: Guiding the college students pay attention to the national development, and to the right side of thinking, actively safeguard national interests; Guiding the youth to learn to distinguish right from wrong, and form a correct global vision and the soul of thought; Through the education of higher vocational college students to learn ecological security concept of national overall security, enhance their awareness of environmental protection, ecological security and the ability to consciously maintain ecological security.

The atom‐transfer radical addition (ATRA) reaction simultaneously forges carbon‐carbon and carbon‐halogen bonds. However, frequently‐used photosensitizers such as precious transition metal complexes, or organic dyes have limitations in terms of their potential toxicity and recyclability. Three β‐ketoenamine‐linked covalent organic frameworks (COFs) from 1,3,5‐triformylphloroglucinol and 1,4‐phenylenediamines with variable transient photocurrent and photocatalytic activity have been prepared. A COF bearing electron‐deficient Cl atoms displayed the highest photocatalytic activity toward the ATRA reaction of polyhalogenated alkanes to give halogenated olefins under visible light at room temperature. This heterogeneous photocatalyst exhibited good functional group tolerance and could be recycled without significant loss of activity. [ABSTRACT FROM AUTHOR]

Zirconia toughened alumina (ZTA) has a wide range of applications in high temperature. Though some routes were reported to enhance the mechanical properties at room temperature, the preparation of ZTA with improved high temperature properties was still unknown. In this work, cordierite/ZTA pre‐stressed ceramics (marked as Cor‐ZTA30) have been fabricated successfully by using prestressed coating reinforcement method. The relationships among the temperature, residual stress and the flexural strength of Cor‐ZTA30 have been established based on experimental data. Due to the compressive stresses exists in the surface layer of Cor‐ZTA30 hinder the crack extension, the flexural strength of Cor‐ZTA30 was greatly enhanced at the temperatures below 1000°C. In addition, the difference in flexural strength between coated and uncoated ZTA ceramics decreased with increasing temperature until 1000°C. It indicated that the residual stress vanished entirely as the temperature above 1000°C, which resulted in the same flexural strength for ZTA and Cor‐ZTA30. Therefore, strengthening ZTA ceramics by prestressing is available under the temperatures below 1000°C. [ABSTRACT FROM AUTHOR]

Under the background of "double reduction" policy, study trip, as an emerging industry integrating educational reform and tourism, have shown a positive development trend Based on Arc GIS spatial analysis, Wechat content search, Wechat index and other analysis methods, this paper takes 120 study tourism bases in Jiangxi province as research objects to analyze the development status of their quantity distribution, subject classification, subject support, spatial differentiation and market recognition, and identify the homogenization problems, security system problems, curriculum problems, study tutor problems, process management problems and marketing effect problems that restrict its high-quality development. Finally, in view of these problems, the paper proposes the following countermeasures: to excavate characteristic resources and pay attention to the construction of high-quality study curriculum system; to improve infrastructure and highlight the construction of high-quality study guarantee system; to innovate training methods and strengthen the building of high-quality study talents; to optimize the management mode and highlight the construction of high-quality process management system; to strengthen marketing awareness and to achieve effective promotion of high-quality brand advantages. [ABSTRACT FROM AUTHOR]

The fungal genus Nigrospora is known to be a plant pathogen, endophyte, and saprobe, and it is usually isolated from various substrates like soil and air. During the surveys of soil fungi in Hebei Province of China, two isolates of Nigrospora were obtained. A multi-locus phylogeny of combined loci of the 5.8S nuclear ribosomal gene with the two flanking transcribed spacers (ITS), part of the translation elongation factor 1-alpha (tef1), and the beta-tubulin (tub2) loci, in conjunction with morphological characters were used to identify the newly collected isolates. Nigrospora humicola sp. Nov. is described and proposed herein, which differs from its phylogenetically close species N. chinensis and N. globosa by the sequences of ITS, tef1, and tub2. [ABSTRACT FROM AUTHOR]