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Objective: This study aimed to explore the aroma differences of Pixian bean paste from different brands and establish an analytical method for quality evaluation and quality control methods in Douban Sauce, based on solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) techniques along with sensory evaluation. Methods: Three different brands of Pixian Douban Sauce were selected as the research objects. SPME and GC-MS techniques were used to extract and qualitatively analyze the aroma components, and the sensory evaluation of the three types of Pixian Douban Sauce was conducted based on current effective group standards. Results: 57, 90, and 70 volatile flavor compounds were identified in brands T, J, and C Pixian Douban Sauce, and 46, 70, and 60 were identified in the database. Excluding impurity peaks and extremely low content fragment peaks, the flavor substances of brands T, J, and C are 32, 47, and 43, respectively. Brand J has the highest sensory rating, followed by brand T, and brand C has the lowest. Based on the analysis of aroma components and content, the relative content of 3-methylbutyraldehyde and 2-methylbutyraldehyde (both with apple aroma and a pleasant feeling) in brand J is higher than the other two brands, and only furfural with a relative content greater than 3% was detected in brand C. Conclusion: The combination of SPME-GC-MS technology and sensory evaluation analysis can distinguish the aroma components of different brands of Pixian Douban Sauce.

Objective Risk stratification is challenging in patients with acute ST segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PCI). We investigated the prognostic value of a novel score system combining leucocyte and platelet counts (COL-P) scores for in-hospital and long-term adverse outcomes.Design This was a retrospective cohort study of patients with STEMI.Setting First Affiliated Hospital of Xinjiang Medical University.Participants A total of 854 STEMI patients with primary PCI were included in this study from November 2009 and December 2015.Primary and secondary outcome measures Major adverse cardiovascular events (MACEs).Methodology The patients were divided into three groups according to the COL-P scores (0, 1 and 2). Cox regression analysis was used to investigate the relation between adverse outcomes and the COL-P score in patients with STEMI.Results A total of 44 patients died in hospital, and 99 within 3-year follow-up after discharge. The in-hospital and 3-year mortality and MACEs were higher in patients with higher COL-P score. Multivariable Cox regression indicated COL-P score was independently associated with long-term mortality (COL-P 1 vs COL-P 0: HR 2.07, 95% CI 1.016 to 5.567, p=0.005; COL-P 2 vs COL-P 0: HR 5.02, 95% CI 1.990 to 9.041, p

At present, the infrastructure for intelligent construction of grain storage depots in our country is relatively complete.However, there is still a lack of systematic research on the construction of intelligent monitoring and early warning systems for insects.The common intelligent monitoring and early warning systems for stored grain pests based on image recognition, infrared photoelectric, acoustic detection,capacitive sensors and other technologies were summarized.The advantages and limitations of each technology are compared in this paper.At present, improving the data set capacity, counting accuracy and recognition accuracy of the intelligent monitoring system are the key technologies.Based on multi-field coupling theory, establish a mathematical model for population growth of different pests and the corresponding expert decision-making system to form the industrial chain of detection and early warning and control, which is the development direction of intelligent grain depot in the future.The industrial chain of prevention and control is the direction of the future development of intelligent grain depots.This article systematically summarizes the latest research results to help promote the construction of intelligent grain depots in my country's grain storage industry.

As a series of novel organic/inorganic hybrid nanomaterials, nanostructured POSS(polyhedral oligomeric silsesquioxanes) particles are one of the best choices for molecular structure design and modification owing to their fascinating physical and chemical properties. The preparation of functionalized POSS has attracted widespread attention, and it is of major academic significance to investigate the synthesis methods and reaction mechanism in depth. The development process and structural characteristics of POSS were summarized and the synthesis methods of functionalized POSS commonly used in polymer modification were reviewed in this paper, including silane hydrolysis/condensation reactions, functional group transformation derivation method and corner-capping reactions. The nanomaterials investigated in this review include methylacryloxypropanyl-POSS, vinyl-POSS, amino-POSS, epoxy-POSS, hydroxyl-POSS and partial mono-functional POSS. Finally, the influencing factors of these methods were discussed and the domestic research on functionalized POSS was prospected:the future research will focus on the further clarification of the synthesis mechanism and the stability of the existing processes for reducing the cost based on the improvement of the yield and providing technical support for industrial production;likewise, the introduction of functional groups can be precisely designed to prepare additional up-to-date reactive POSS.

The Chinese mole shrew, Anourosorex squamipes Milne-Edwards, 1872, is a common species of insectivorous mammal in Southwest China. Based on field investigations between 2001 and 2019, the present study reports the infestation of chiggers (larvae of chigger mites) on the shrew in Southwest China and certain ecology parameters for the first time. A total of 3169 chiggers were collected from 1694 A. squamipes and they were identified into 72 species and 10 genera in the family Trombiculidae. The overall infestation prevalence (Pm), mean abundance (MA) and mean intensity (MI) of A. squamipes with chiggers reached 11.1%, 1.87 and 16.86, respectively. The species diversity, species composition and infestation of chiggers on A. squamipes fluctuated in different environments (latitudes, altitudes, habitats and landscapes) and on different sexes and ages of the shrew hosts with high heterogeneity and low species similarity. In the established linear regression equation (M* = 0.173 + 1.054 M) for dominant mite Leptotrombidium densipunctatum, both the α and β values (α = 0.173, β = 1.054) exceeded the boundary values (F = 4.67, p

Because of lower inductance and higher commutation frequency, caused by high-frequency current harmonics induced by the PWM control, super high speed permanent magnet brushless motors commonly face overheating of both the rotor and stator. For chopping directly at the inverter, the frequency should be increased to reduce the current harmonics. But for the 10 kW class motor drives used in the air compressors of fuel cell vehicles, the power switch devices currently do not fulfill the needs of switch frequency and power simultaneously. Therefore, it is not a good choice to regulate the speed by chopping at the inverter. Aimed at reducing losses in the stators and rotors, this paper presented the design of a pre-Buck square wave drive for reducing current harmonics. By optimizing the back electromotive force (EMF) filter circuit and commutation compensation angle, the operation range of sensorless control CAN was extended to 3000-100000 r·min-1. The key points encountered during the drive development were analyzed and solutions proposed. Finally, the excellent performance of the drive was demonstrated by experiment.