323 research outputs found
Teager energy enhancement base on polar coordinates at angular domain and feature extraction of bearing’s early fault
Unstable signal under variable rotation speed condition can expose bearing’s weak fault feature more obviously, a method of Teager energy enhancement base on polar coordinates at angular domain (TEEPAD) is proposed in this paper to analyze the unstable signal and extract single or concurrent fault of bearing’s early failure. Firstly, order analysis is selected to resample the unstable signal in time domain to stationary signal in angular domain, then Teager energy operator of stationary signal in angular domain is calculated and projected on the polar coordinates plane to enhance the fault feature. Analysis result of actual signal shows that single or concurrent fault feature of bearing’s early failure is effectively extracted by TEEPAD, and the other components having different periods or random noise are restrained synchronously
Effects of preheating temperatures on the formation of sandwich compression and density distribution in the compressed wood
Release Profile of Nitrogen during Thermal Treatment of Waste Wooden Packaging Materials
In this paper, the fast pyrolysis experiment of particle board was carried out on a fixed bed reactor and a Py-GC/MS equipment. The effects of temperature and gas phase residence time on the product yields and its components distribution were investigated. The effect of components of particle board on product yields and its components distribution was also investigated. The results showed that the temperature has a great influence on the yields of fast pyrolysis products, and the yield of pyrolysis oil reached the highest at 550°C. The urea-formaldehyde resin would prevent the pyrolysis of particle board. Compared with the bio-oil from fast pyrolysis of wood, the major components of the bio-oil from fast pyrolysis of particle board did not change much
PO-093 Effects of 6-week hypoxic exercise on aerobic capacity-related proteins in overweight/obese women
Objective To explore the effects of hypoxic and normoxic exercise on hemoglobin (Hb), erythropoietin (EPO), hypoxia-inducible factor 1α (HIF1α) and vascular endothelial growth factor (VEGF) in overweight women.
Methods This study enrolled 40 female overweight/obese subjects, age is among 18-47 years old, with no abnormal physical examination. The overweight standard is BMI ≥ 24, and the obesity standard is BMI ≥ 28. All subjects were paired according to body weight, divided into hypoxia group and normoxia group, doing 6 weeks of exercise intervention, 3 times a week, every next day one time. The exercise intervention includes 30 minutes of strength training and 30 minutes of endurance training. There are 5 minutes of warm up before training and 5 minutes cool down after the training. Strength training uses the device as a dumbbell. The training content consists of 8 movements, there are dead lift, upright row, squat, shoulder press, calf Jump, advance junge, biceps curl and triceps extension, and the weight is 12RM. 2 sets for each action, rest between sets is 30s. Endurance training uses a treadmill with a slope of 0°, and the speed is adjusted according to the target heart rate interval. The calculation method of the target heart rate interval is (220-age)×60%~(220-age)×70%. Among them, the hypoxic group is equipped with a suction-type atmospheric hypoxic device, which moves with low-oxygen environment, and the oxygen content of the inhaled mixed gas is 16%; the normoxic group moves with normal oxygen environment. Nutritional education was given to all subjects prior before the start of exercise intervention, but diet was not restricted during the intervention. Fasting venous blood was taken before and after Fasting venous blood before and after exercise intervention intervention, and Hb, EPO, HIF1α, and VEGF were detected. All the test results were expressed by mean±standard deviation (x±SD). The data between two groups were compared by non-parametric Mann-Whitney U test. The intra-group data were compared using a nonparametric Wilcoxon match for the symbol level test, with a significance level of P < 0.05 and a very significant level of P < 0.01.
Results After the intervention, the Hb level in the hypoxic group was increased, but there was no significant difference compared with the pre-intervention group (P>0.05). There was no significant difference in the Hb change rate between the hypoxic group and the normoxic group (P>0.05). The EPO level in the hypoxic group was significantly increased, and there was a statistically significant difference compared with the pre-intervention group (P<0.01). There was no significant change in the EPO level in the normoxic group (P>0.05). The EPO change rate in the hypoxic group was compared with the normoxic group. There was no statistical difference (P>0.05). The level of HIF1α in the hypoxic group was significantly higher than that before the intervention (P<0.01). The level of HIF1α in the normoxic group was significantly lower than that before the intervention (P<0.01). The rate of change of HIF1α in the oxygen group was statistically different from that in the normox group (P<0.01). The level of VEGF in the hypoxic group was increased, but the level of VEGF in the normoxic group was decreased, but there was no significant difference compared with the pre-intervention group (P>0.05). There was no significant difference in the rate of VEGF in the hypoxic group compared with the normoxic group(P>0.05).
Conclusions Compared with normotensive exercise, 6-week exercise increased the levels of Hb and EPO in overweight women, but the difference between hypoxia and normoxia was not significant. The level of HIF1α in the hypoxic group was increased, and the level of HIF1α in the normoxic group was decreased. This index was significantly affected by hypoxia. The level of VEGF in the hypoxic group was increased, and the level of VEGF in the normoxic group was decreased, but the effects of hypoxia and exercise were not obvious
Optimization of bonding parameters of laminated wood using a novel bio-based RPF adhesive
Adhesive is the key component and factor for the manufacture of glulam, affected both the properties and cost of glulam product. Bio-based resorcinol-phenol-formaldehyde (BRPF) resin was developed by partly replacing the expensive resorcinol and phenol with the cheap biomass derived pyrolysis oil. The press process parameters and the dosage of adhesive and corresponding curing agent were selected as the factors and extensively studied. BRPF resin was successfully used to bond the laminas to produce glulam, and the optimized process parameters for the cold-pressing adhesion of BRPF resin with pine wood were obtained as follows: the cold-pressing pressure 1.4 MPa, the cold-pressing time 9 h, the amount of adhesive coating 320 g/m2, and the proportion of curing agent (poly-formaldehyde) 17%. The mechanical performances of laminated wood bonding with BRPF resin under the optimal condition were further verified. It is believed that the results obtained here will promote the use of bio-based resin in the bonding of laminated wood, and then contribute to the green manufacturing of glulam with lower cost
Angiotensin-converting enzyme inhibitor promotes angiogenesis through Sp1/Sp3-mediated inhibition of notch signaling in male mice
Epstein-Barr virus transcription factor Zta acts through distal regulatory elements to directly control cellular gene expression
Lytic replication of the human gamma herpes virus Epstein-Barr virus (EBV) is an essential prerequisite for the spread of the virus. Differential regulation of a limited number of cellular genes has been reported in B-cells during the viral lytic replication cycle. We asked whether a viral bZIP transcription factor, Zta (BZLF1, ZEBRA, EB1), drives some of these changes. Using genome-wide chromatin immunoprecipitation coupled to next-generation DNA sequencing (ChIP-seq) we established a map of Zta interactions across the human genome. Using sensitive transcriptome analyses we identified 2263 cellular genes whose expression is significantly changed during the EBV lytic replication cycle. Zta binds 278 of the regulated genes and the distribution of binding sites shows that Zta binds mostly to sites that are distal to transcription start sites. This differs from the prevailing view that Zta activates viral genes by binding exclusively at promoter elements. We show that a synthetic Zta binding element confers Zta regulation at a distance and that distal Zta binding sites from cellular genes can confer Zta-mediated regulation on a heterologous promoter. This leads us to propose that Zta directly reprograms the expression of cellular genes through distal elements
Thermodynamically favorable reactions shape the archaeal community affecting bacterial community assembly in oil reservoirs
Microbial community assembly mechanisms are pivotal for understanding the ecological functions of microorganisms in biogeochemical cycling in Earth’s ecosystems, yet rarely investigated in the context of deep terrestrial ecology. Here, the microbial communities in the production waters collected from water injection wells and oil production wells across eight oil reservoirs throughout northern China were determined and analyzed by proportional distribution analysis and null model analysis. A ‘core’ microbiota consisting of three bacterial genera, including Arcobacter, Pseudomonas and Acinetobacter, and eight archaeal genera, including Archaeoglobus, Methanobacterium, Methanothermobacter, unclassified Methanobacteriaceae, Methanomethylovorans, Methanoculleus, Methanosaeta and Methanolinea, was found to be present in all production water samples. Canonical correlation analysis reflected that the core archaea were significantly influenced by temperature and reservoir depth, while the core bacteria were affected by the combined impact of the core archaea and environmental factors. Thermodynamic calculations indicate that bioenergetic constraints are the driving force that governs the enrichment of two core archaeal guilds, aceticlastic methanogens versus hydrogenotrophic methanogens, in low- and high-temperature oil reservoirs, respectively. Collectively, our study indicates that microbial community structures in wells of oil reservoirs are structured by the thermodynamic window of opportunity, through which the core archaeal communities are accommodated directly followed by the deterministic recruiting of core bacterial genera, and then the stochastic selection of some other microbial members from local environments. Our study enhances the understanding of the microbial assembly mechanism in deep terrestrial habitats. Meanwhile, our findings will support the development of functional microbiota used for bioremediation and bioaugmentation in microbial enhanced oil recovery
Tracheobronchial foreign bodies in children – a retrospective study of 2,000 cases in Northwestern China
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