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Hot air drying is the most common drying and processing technology for agricultural products. However, the shortcomings of single hot air drying technology limit its efficient and high-quality application. Coupling with the characteristics of two or more drying technologies, the combined drying technology can form complementary advantages. In this paper, the existing superheated steam-hot air, ultrasonic-hot air, freezing-hot air, microwave-hot air, radio frequency -hot air, infrared -hot air, heat pump -hot air and vacuum -hot air in total 8 kinds of combined hot air drying technology applications and related equipment were comprehensively summarized, whereas further applicable conditions and equipment operating conditions were compared. Finally, the development trend and challenges of hot air and its combined drying technology were discussed, which provided a reference for the efficient application of hot air and its combined drying technology in actual production and life. [ABSTRACT FROM AUTHOR]

In order to study the influence of hovering helicopters on the flow field characteristics around a warship deck, numerical simulation is carried out on the coupling flow field of multiple helicopter rotors and warship using Fluent software. The flow field structure, helicity distribution and turbulent kinetic energy are mainly analyzed under different wind direction conditions. Simulation results show that parameters of flow field around each helicopter rotor couple and affect each other. Crosswind makes the flow field structure more disorderly, and the incoming flow, multiple helicopter rotors and superstructure generate the mixed flow field. Also, the zone of turbulent kinetic energy exceeding the limit covers the whole deck, which is bad for helicopter landing. [ABSTRACT FROM AUTHOR]

Objective: To understand and analyze the rules of endurance exercise on the cerebral cortex adaptive mechanism in aged rats., Methods: In this study, 3-month-old (n=20), 13-month-old (n=24) and 23-month-old (n=24) specific-pathogen free (SPF) male Sprague-Dawley Rat (SD) rats were divided into young (Y-SED), middle-aged (M-SED) and old-aged (O-SED) sedentary control group, and the corresponding Y-EX, M-EX and O-EX in the endurance exercise runner group. The 10-weeks of regular moderate-intensity aerobic exercise intervention were carried out in the endurance exercise runner group. The exercise mode is treadmill exercise (slope 0), and the exercise intensity gradually increases from 60%～65% of the maximum oxygen consumption (V·O 2max ) to 70%～75%, and the exercise time is 10 weeks. Hematoxylin and eosin (HE) staining was used to detect age-related morphological changes. The expressions of superoxide dismutase(SOD) and brain-derived neurotrophic factor (BDNF) and the expressions of synapsin 1 (SYN1) and Ca 2+ /calmodulin- dependent protein kinases IIα (CaMK IIα) / AMP-activated protein kinase α1(AMPKα1) / mammalian target of rapamycin (mTOR) pathway -related genes were detected., Results: The cerebral cortex structure of the rats in each group showed age-related aging changes, the expression of SOD in the cortex showed a gradual decline, the expression of BDNF showed an age-increasing trend, and the expression levels of SYN1 and CaMK IIα were increased with age. The changes in AMPKα1 and SirT2 and IP3R, AKT1 and mTOR mRNA levels were increased slightly in middle-aged rats and decreased in aged rats. Compared with the rats in each sedentary control group, the nucleus of the cerebral cortex was tightly arranged and the number of nuclei observed under the microscope was increased significantly in each exercise group. Exercise promoted the expressions of SOD, BDNF and synaptophysin SYN1 in the cortex of rats, and the expression levels of SOD and BDNF in aged rats were up-regulated significantly (P＜ 0.01). The expression level of SYN1 in rats was up-regulated significantly (P＜0.05) in the young and aged rats. The expression of CaMK IIα in the cortex of middle-aged and aged rats was up-regulated (P＜0.01), while the expression level of CaMK IIα in young rats was down-regulated (P＜0.01). Exercise could up-regulate the expression level of AMPKα1 in the cortex of young rats (P＜ 0.05), but not in middle-aged and old-age rats. Exercise could up-regulate the expression of SirT2 in the cortex of rats in all age groups (P＜0.05). Exercise up-regulated the expression of phosphoinositide 3-kinase (IP3R)/ protein kinase B 1(AKT1) /mTOR in the cortex of rats, among which young IP3R was significantly up-regulated (P＜0.01) in the young group, mTOR was significantly up-regulated in young and middle-aged group (P＜0.01), and mTOR was also significantly up-regulated in the aged group (P＜0.05)., Conclusion: Endurance exercise up-regulates BDNF expression, regulates CaMKIIα signaling, activates AMPK signaling pathway and IP3R / AKT1 / mTOR signaling pathway, and improves synaptic plasticity in the cortex.

Objective: To study the effect of different intensity exercise on skeletal muscle fiber myosin heavy chain(MHC) subtype transformation and CaN/NFATc1 signaling pathways., Methods: Twenty-four Male SD rats (2-month old) were randomly divided into normal control group (NC), moderate intensity exercise group (ME, grade 5°, speed 18 m/min), heavy intensity exercise group (HE, grade 10°, 26.8 m/min). The rats in exercise groups were treated with treadmill training for eight weeks. The type I and type Ⅱ muscle fibers were determined by ATPase staining method. MHC subtype was separated by SDS-PAGE. The activity of CaN was determined by colorimetric method. The content of NFATc1 protein in skeletal muscle was detected by immune imprinting technology., Results: ①Skeletal muscle fiber density changes:the type I and Ⅱ fiber number density of quadriceps in ME group were increased significantly ( P <0.05), but in HE group, only the type Ⅱ fiber surface density was increased significantly ( P <0.05). The type I fiber number density of soleus in ME and HE group was increased significantly ( P <0.05). ②The changes of fibers MHC subtype percentage in skeletal muscle:the percentages of MHC I and type Ⅱa of quadriceps in ME group were increased ( P <0.05), while the percentage of MHC Ⅱb was decrease ( P <0.05). The percentage of MHC I in soleus was increased, while the percentages of MHCⅡa and Ⅱb were decreased. ③The activity of CaN and the content of NFATc1 protein in ME group were increased significantly ( P <0.05)., Conclusions: The heavy and moderate intensity exercise may induce skeletal muscle MHC type transforming from fast to slow. At the same time, the activity of CaN and the expression of NFATc1 protein are increased accompanying the changes of skeletal muscle fibers subtype.

The diffuse-reflectance FTIR spectroscopy (DRIFTS) and attenuated total reflection FTIR (ATR-FTIR) were used to study polygonum multi florum Thumb and its extracts. The result shows that when acetone is used as extraction agent, the contents of extracts in polygonum multi florum Thunb's phloem are highest, those in polygonum multi florum Thunb's xylem are the lowest. Compared with DRIFTS and ATR-FTIR, it can be found that there are some differences between polygonum multi florum Thunb and its extracts. There are two gentle absorption peaks at 3 576 and 3 147 cm(-1) respectively for polygonum multi florum Thunb, while there is a strong absorption peak at 3 351 cm(-1) for its extracts, showing that there may be more OH... active ingredients in polygonum multi florum Thunb's extracts. Meanwhile, polygonum multiflorum Thunb has strong absorption peaks at 931, 859, 766 and 709 cm(-1) respectively, while its extracts have no resembling absorption peaks. It also shows that the extracts are active ingredients.

Objective: To reveal the effects of three days' repeated exhausted eccentric exercise on the skeletal muscle apoptosis and proliferation in rats., Methods: Fifty male SD rats aged at 8 week old were randomly divided into control group (C) and training groups (B1, B2, B3, B4) (n = 10), the training groups ran on a treadmill every day till exhausted. After they had been trained repeatedly for three days, their medial head of triceps brachii muscle cell apoptosis was detected in paraffin section by the TUNEL, expression of proliferating cell nuclear antigen (PCNA) protein was examined by immunohistochemistry., Results: (1) The apoptosis appeared sequential change, and it was consistent with the exercise-induced skeletal muscle micro-injury (EIMmI). The apoptosis index in the training group after exercise was much greater than that in the control group (P < 0.05), and it reached the peak at 24 h after exercise, then it reduced at 48 h after exercise. (2) The express of PCNA exhibited a sequential change after exercise, the proliferation index in the training group after exercise was greater than that in the control group (P < 0.05), it increased after exercise immediately, but it reduced at 3 h after exercise, then was reached the peak at 24 h after exercise, the proliferation index was moderately correlated with the apoptosis index (P < 0.05)., Conclusion: (1) Cell apoptosis can induce the delayed skeletal muscle damage. (2) Apoptosis may be a start factor of skeletal muscle regeneration.

In-situ attenuated total reflection FTIR (in situ ATR-FTIR) was used for the dynamic research on the residual of pesticide. The in-situ characterization of dichlorvos and orthene on the tomatoes' surface shows that the dichlorvos has obvious volatility and its degradation amount is 80% 20 minutes after spraying. Meanwhile, the ATR-FTIR shows that the strong absorption peak of dichlorvos at 1 734 cm(-1) turns to negative peaks and the absorption peaks at 3 073 cm(-1) significantly abate. The absorption peaks at 1 277 cm(-1) become weak and red shift (30 cm(-1)) shows that the dichlorvos may be hydrolyzed to some extent. While the absorption peaks of orthene show no change 120 minute after spraying. It shows that the orthene is relatively stable.

A new method for the determination of the total volatile basic nitrogen (TVB-N) by reflectance spectroscopy was developed. The method was based on the reaction of TVB-N with Nessler's reagent treated by molecular sieve and the reflectance-absorption value F(R), which is directly proportional to the amount of NH2 Hg IO in solid phase, was measured by the reflection spectrometer. The fundamental principle, effective factors and experimental conditions of the method were discussed. The special features of this method were its simplicity in operation, relatively high sensitivity of determination and the use of a small amount of reagent. Linear calibration graph was obtained in the range 1-8 microg x mL(-1) with a detection limit of 0.1 microg x mL(-1). The method was applied to monitor the fresh degree of fish and pork. The result discovered that the total volatile basic nitrogen increased rapidly along with the time extension, indicating that the deterioration of fish and pork was an acceleration process, and the deterioration speed of fish was faster than that of pork.

Objective: To observe the changes in intracranial pressure (ICP) and brain tissue oxygen tension (PO(2)) and their significance in severe head injury treated by moderate hypothermia (33-35 degrees Celsius)., Methods: Eighteen patients with severe head injury were treated with moderate hypothermia group and probes were deployed in the cerebral cortex for measuring their ICP and PO(2) under continuous monitoring. Another 14 similar patients receiving the same treatment but without hypothermia served as the control group., Results: In moderate hypothermia group the ICP gradually decreased and PO(2) increased after 24 hours of hypothermia, with obvious difference from the control group (P<0.05)., Conclusion: Moderate hypothermia can obviously reduce ICP and improve brain tissue oxygen metabolism to lower the morbidity and mortality rate of severe head injury.