A63: Exercise Improves Appetite and Heart Function in High Fat Drosophila

Purpose: High-fat diets cause obesity and disease leading to excess appetite and cardiovascular disease. At present, there is literature showing the improvement effect of exercise on obesity and related diseases. To explore more deeply the mechanism of action of exercise on appetite improvement and heart function in high-fat diets, we used fruit fly motility models to reveal this aspect of function. Methods: A total of 300 wild-type W1118 virgin flies that matured within 12 hours were collected. They were randomly divided into 100 animals in the normal diet control group (NFD), 100 in the high-fat diet group (HFD), and 100 in the high-fat diet exercise group (HFD+E). Exercise intervention for 7-day-old fruit flies for 5 consecutive days. An EM-CCD high-speed camera was used to record the heartbeat of fruit flies (video at 130 fps, the 30 s), and HC Image software was used to record the cardiogram data. Semi-Automated Optical Heartbeat Analysis (SOHA) quantifies Heart Rate (HR), Heart Period (HP), Diastolic Intervals (DI), Systolic Intervals (SI), Arrhythmia Index (AI), Diastolic Diameter (DD), Systolic Diameter (SD), Fractional Shortening (FS), and Fibrillations (FL). Fruit fly uptake was measured using the FlyPAD high-throughput Drosophila quantitative feeding system. All fruit flies needed to be fed on normal medium for 5 days first and then transferred to fresh normal medium or the high-fat medium on the 6th day for another 2 days. NFD flies are placed in a constant temperature and humidity incubator (25 ℃, 50% humidity, 12 h day and night cycle), HFD flies are housed in incubators at 22-24 ℃ and 50% relative humidity to make high-fat medium by mixing 30% coconut oil and 70% standard medium. Results: The HFD group had an increase in AI, HR and HP, constant SD, decreased DD, and decreased FS. After exercise, HFD+E group had a decrease in HR, an increase in HP, an improvement in AI, an improvement in DD, and no change in SD. The food intake and sipping frequency of fruit flies in the HFD group were significantly higher than those in the NFD group, and during the same time period, the food intake and number of sipping times in the HFD+E group and the HFD group decreased significantly after exercise. Conclusion: Exercise improved excess appetite and cardiac dysfunction in high-fat diets

Modulation of Metabolome and Bacterial Community in Whole Crop Corn Silage by Inoculating Homofermentative Lactobacillus plantarum and Heterofermentative Lactobacillus buchneri

The present study investigated the species level based microbial community and metabolome in corn silage inoculated with or without homofermentative Lactobacillus plantarum and heterofermentative Lactobacillus buchneri using the PacBio SMRT Sequencing and time-of-flight mass spectrometry (GC-TOF/MS). Chopped whole crop corn was treated with (1) deionized water (control), (2) Lactobacillus plantarum, or (3) Lactobacillus buchneri. The chopped whole crop corn was ensiled in vacuum-sealed polyethylene bags containing 300 g of fresh forge for 90 days, with three replicates for each treatment. The results showed that a total of 979 substances were detected, and 316 different metabolites were identified. Some metabolites with antimicrobial activity were detected in whole crop corn silage, such as catechol, 3-phenyllactic acid, 4-hydroxybenzoic acid, azelaic acid, 3,4-dihydroxybenzoic acid and 4-hydroxycinnamic acid. Catechol, pyrogallol and ferulic acid with antioxidant property, 4-hydroxybutyrate with nervine activity, and linoleic acid with cholesterol lowering effects, were detected in present study. In addition, a flavoring agent of myristic acid and a depression mitigation substance of phenylethylamine were also found in this study. Samples treated with inoculants presented more biofunctional metabolites of organic acids, amino acids and phenolic acids than untreated samples. The Lactobacillus species covered over 98% after ensiling, and were mainly comprised by the L. acetotolerans, L. silagei, L. parafarraginis, L. buchneri and L. odoratitofui. As compared to the control silage, inoculation of L. plantarum increased the relative abundances of L. acetotolerans, L. buchneri and L. parafarraginis, and a considerable decline in the proportion of L. silagei was observed; whereas an obvious decrease in L. acetotolerans and increases in L. odoratitofui and L. farciminis were observed in the L. buchneri inoculated silage. Therefore, inoculation of L. plantarum and L. buchneri regulated the microbial composition and metabolome of the corn silage with different behaviors. The present results indicated that profiling of silage microbiome and metabolome might improve our current understanding of the biological process underlying silage formation

Failure Characteristics and Scale in a Sandstone Joint Subjected to Direct Shear Testing: Experimental Investigation with Acoustic Emission Monitoring

AbstractAn in-depth recognition of the failure characteristics and scale of joints is of great significance for the stability assessment in rock engineering. Unfortunately, due to the close fitting of the upper and lower blocks of the joint under direct shear tests, the shear failure of joints are difficult to observe directly during the shear process. Thus, in this work, direct shear tests were carried out on sandstone joints subjected to three levels of normal stress while the acoustic emission (AE) in the rock is synchronously monitored. The failure characteristics of rock joints were then investigated by calibrating the AE system and combining them with the AE location results and shear load curves. A method was established to determine the failure scale of the rock joint that uses the AE moment tensor and first law of thermodynamics. The results show that the degree of failure of the rock joints increases as the normal stress increases. Also, the shear failure of the rock joints is localized and occurs synchronously, rather than sequentially in different areas. The average length of the microfractures formed in the shear process correlates with the average mineral grain size. On the other hand, the maximum length of the microfractures appears to have different values depending on the normal stress present. Our results have significant reference value for the precursory identification of shear disaster in engineering rock masses

Bone Mineral Density of the Spine in 11,898 Chinese Infants and Young Children: A Cross-Sectional Study

Background: Bone mineral density (BMD) increases progressively during childhood and adolescence and is affected by various genetic and environmental factors. The aim of this study was to establish reference values for lumbar BMD in healthy Chinese infants and young children and investigate its influencing factors. Methods and Findings: Healthy children aged 0 to 3 years who underwent regular physical examinations at the Child Health Care Clinic of Hubei Maternal and Child Health Hospital (N = 11,898) were recruited for this study. We also chose 379 preterm infants aged 0 to 1 years to preliminarily explore the development of BMD in this special population. BMD (g/cm2) measurements of the lumbar spine (L2–L4) were carried out with dual-energy X-ray absorptiometry and a questionnaire was administered to full-term children's parents to gather information on various nutritional and lifestyle factors as well as mothers' nutritional supplement use during pregnancy. Lumbar BMD significantly increased with age among both boys and girls (p0.05), either among healthy reference children or preterm infants. However, BMD values in preterm infants were significantly lower than those in term infants 3 to 8 months old (p<0.05) after adjustment for gestational age. Multivariable linear regression analysis indicated significant positive associations between lumbar BMD of healthy children and the child's age and current weight, mother's weight gain during pregnancy, birth weight, children's outdoor activity duration and children's physical activity duration. Conclusion: Our study provides reference values of lumbar BMD for healthy Chinese children aged 0 to 3 years and identifies several influencing factors

Nanotube ferroelectric tunnel junctions with giant tunneling electroresistance ratio

Low-dimensional ferroelectric tunnel junctions are appealing for the realization of nanoscale nonvolatile memory devices due to their inherent advantage of device miniaturization. Those based on current mechanisms still have restrictions including low tunneling electroresistance (TER) effects and complex heterostructures. Here, we introduce an entirely new TER mechanism to construct the nanotube ferroelectric tunnel junction with ferroelectric nanotubes as the tunneling region. When rolling a ferroelectric monolayer into a nanotube, due to the coexistence of its intrinsic ferroelectric polarization with the flexoelectric polarization induced by bending, there occurs metal-insulator transition depending on radiative polarization states. For the pristine monolayer, its out-of-plane polarization is tunable by an in-plane electric field, the conducting states of the ferroelectric nanotube can thus be tuned between metallic and insulating via axial electric means. Using {\alpha}-In2Se3 as an example, our first-principles density functional theory calculations and nonequilibrium Green's function formalism confirm the feasibility of the TER mechanism and indicate an ultrahigh TER ratio exceeding 9.9*10^10% of the proposed nanotube ferroelectric tunnel junctions. Our findings provide a promising approach based on simple homogeneous structures for high density ferroelectric microelectronic devices with excellent ON/OFF performance.Comment: 15 pages, 5 figure