31 research outputs found
Leveraging Inlier Correspondences Proportion for Point Cloud Registration
In feature-learning based point cloud registration, the correct
correspondence construction is vital for the subsequent transformation
estimation. However, it is still a challenge to extract discriminative features
from point cloud, especially when the input is partial and composed by
indistinguishable surfaces (planes, smooth surfaces, etc.). As a result, the
proportion of inlier correspondences that precisely match points between two
unaligned point clouds is beyond satisfaction. Motivated by this, we devise
several techniques to promote feature-learning based point cloud registration
performance by leveraging inlier correspondences proportion: a pyramid
hierarchy decoder to characterize point features in multiple scales, a
consistent voting strategy to maintain consistent correspondences and a
geometry guided encoding module to take geometric characteristics into
consideration. Based on the above techniques, We build our Geometry-guided
Consistent Network (GCNet), and challenge GCNet by indoor, outdoor and
object-centric synthetic datasets. Comprehensive experiments demonstrate that
GCNet outperforms the state-of-the-art methods and the techniques used in GCNet
is model-agnostic, which could be easily migrated to other feature-based deep
learning or traditional registration methods, and dramatically improve the
performance. The code is available at https://github.com/zhulf0804/NgeNet
Research Progress of Meat Product Flavor Based on Molecular Sensory Science
Meat products contain a large number of flavor compounds (mainly aroma and taste compounds), but only a few of them affect the final flavor of the product. How to isolate and identify the key aroma or taste compounds from a large number of flavor compounds is a hot issue in the research on the flavor and quality of meat products. Molecular sensory science is a systematic science that integrates analytical chemistry, food sensory evaluation and other disciplines. Its research methods can solve the above problems well. In this paper, the application of molecular sensory science in meat products and the advantages and disadvantages of different analytical techniques are summarized. Meanwhile, the evaluation methods of molecular sensory science are expounded, and the importance of recombination and deletion experiments to further confirm the key flavor components are highlighted. This review provides a certain practical reference and theoretical basis for the research in the field of meat flavor and sensory technology innovation
Aggregation process of two disaster-causing jellyfish species, Nemopilema nomurai and Aurelia coerulea, at the intake area of a nuclear power cooling-water system in Eastern Liaodong Bay, China
The intake safety of nuclear power cooling-water systems (NPCSs) is an important aspect of operational safety of nuclear power plants (NPPs). The blockages caused by aberrant outbreaks of various aquatic organisms have seriously affected operational safety. Large jellyfish constitute the main groups of marine organisms responsible for these blockages. The processes of aggregation and the relationships of two major disaster-causing scyphozoan jellyfish species, Nemopilema nomurai and Aurelia coerulea, with four environmental factors at the intake area of an NPCS in Eastern Liaodong Bay, China, were investigated in 2019 and 2020. The findings revealed that A. coerulea ephyrae were present in the surrounding ports in mid-May; however, N. nomurai ephyrae were absent during the survey period in this study, and the medusae of N. nomurai started appearing from late May. The individual growth and relative biomass (RB) of the jellyfish increased rapidly from late June to July and decreased rapidly thereafter, in September. The RB of N. nomurai was highly correlated to the sea surface temperature (SST) and levels of dissolved oxygen (DO) in the region. The RB increased with increasing SST and decreased at increasing DO levels. The RB of A. coerulea was significantly negatively correlated with that of N. nomurai, and the peak biomass of the two species alternated over time, which could be attributed to the fact that the jellyfish species share similar ecological niches. The bell diameters were significantly positively correlated with the individual wet weights, and the value of one could be inferred from the value of the other. Although the processes of jellyfish aggregation are attributed to several factors, including interactions with environmental factors and human activities, such as fishing, the results obtained in this study would serve as an important reference and provide a basis for the prevention of jellyfish blooms in waters adjacent to NPPs. The prevention and control of jellyfish disasters at the intake area of NPCSs are not only local concerns. Therefore, remediation from the source combined with the maximum utilization of social resources for monitoring and early warning would immensely improve the efficacy of such preventive strategies
Deficient Liver Biosynthesis of Docosahexaenoic Acid Correlates with Cognitive Impairment in Alzheimer's Disease
Reduced brain levels of docosahexaenoic acid (C22:6n-3), a neurotrophic and neuroprotective fatty acid, may contribute to cognitive decline in Alzheimer's disease. Here, we investigated whether the liver enzyme system that provides docosahexaenoic acid to the brain is dysfunctional in this disease. Docosahexaenoic acid levels were reduced in temporal cortex, mid-frontal cortex and cerebellum of subjects with Alzheimer's disease, compared to control subjects (P = 0.007). Mini Mental State Examination (MMSE) scores positively correlated with docosahexaenoic/α-linolenic ratios in temporal cortex (P = 0.005) and mid-frontal cortex (P = 0.018), but not cerebellum. Similarly, liver docosahexaenoic acid content was lower in Alzheimer's disease patients than control subjects (P = 0.011). Liver docosahexaenoic/α-linolenic ratios correlated positively with MMSE scores (r = 0.78; P<0.0001), and negatively with global deterioration scale grades (P = 0.013). Docosahexaenoic acid precursors, including tetracosahexaenoic acid (C24:6n-3), were elevated in liver of Alzheimer's disease patients (P = 0.041), whereas expression of peroxisomal d-bifunctional protein, which catalyzes the conversion of tetracosahexaenoic acid into docosahexaenoic acid, was reduced (P = 0.048). Other genes involved in docosahexaenoic acid metabolism were not affected. The results indicate that a deficit in d-bifunctional protein activity impairs docosahexaenoic acid biosynthesis in liver of Alzheimer's disease patients, lessening the flux of this neuroprotective fatty acid to the brain
Land Use Change and Its Impact on Landscape Ecological Risk in Typical Areas of the Yellow River Basin in China
The basic premise of regional ecological construction would be to scientifically and effectively grasp the characteristics of land use change and its impact on landscape ecological risk. The research objects of this paper are the typical areas of the Yellow River Basin in China and “process-change-drive” as the logical main line. Moreover, this paper is based on multi-period land use remote sensing data from 2000 to 2020, the regional land use change process and influencing factors are identified, the temporal and spatial evolution and response process of landscape ecological risk are discussed, and the land use zoning control strategy to reduce ecological risk is put forward. The results indicated: (1) The scale and structure of land use show the characteristics of “many-to-one” and “one-to-many”; (2) the process of land use change is affected by the alternation of multiple factors. The natural environment and socio-economic factors dominate in the early stage and the location and policy factors have a significant impact in the later stage; (3) the overall landscape ecological risk level and conversion rate show a trend of “high in the southeast, low in the northwest”, shift from low to high and landscape ecological risks gradually increase; and (4) in order to improve the regional ecological safety and according to the characteristics of landscape ecological risk and spatial heterogeneity, we should adopt the management and control zoning method and set different levels of control intensity (from key intensity to strict intensity to general intensity), and develop differentiated land use control strategies
Does Dietary Lipid Level Affect the Quality of Triploid Rainbow Trout and How Should It Be Assessed?
Organoleptic properties and nutritional value are the most important characteristics of fish fillet quality, which can be determined by a series of quality evaluation indexes and closely related to fish nutrition. Systematic organoleptic and nutritional quality evaluation indexes consisting of 139 indexes for physical properties and chemical compositions of triploid rainbow trout were established. Besides, effects of dietary lipid levels (6.6%, 14.8%, 22.8% and 29.4%) on the quality of triploid rainbow trout were analyzed in the study. The main results showed that, for fillet appearance quality, fish fed diets with lipid levels above 22.8% had higher fillet thickness and redness but lower gutted yield and fillet yield (p p p p < 0.05). For nutritional value, a high lipid diet could increase the lipid nutrition level (such as the content of long chain polyunsaturated fatty acids increased from 3.47 to 4.41 g/kg muscle) but decease tryptophan and selenium content (from 2.48 to 1.60 g/kg muscle and from 0.17 to 0.11 g/kg muscle, respectively). In total, a high lipid diet could improve the quality of triploid rainbow trout. The minimum dietary lipid level for triploid rainbow trout should be 22.8% to keep the better organoleptic and nutritional quality
“In-Between Area” Design Method: An Optimization Design Method for Indoor Public Spaces for Elderly Facilities Evaluated by STAI, HRV and EEG
The indoor public spaces of most elderly facilities in China have a monotonous space form, which, thus, causes low comprehensive performance and is less likely to satisfy participants’ various requirements. This study proposes an optimization design method of “In-Between Area” for a space form operation to improve the performance of indoor public spaces. First, two models were established: Model A to reflect current indoor public spaces and Model B to represent the indoor public spaces designed by using the “In-Between Area” method. Second, a walk-through video was created from each model, with a duration of 196 s. Subjective assessment (STAI) data and objective physiological data (HRV and EEG), were collected from 40 participants while they were watching walk-through videos. The comparison analysis showed statistically significant differences between Model A and Model B. The results of STAI, HRV and EEG proved that the “In-Between Area” method, as an optimization design method, created a more pleasant and comfortable environment for the elderly and improved the overall efficiency of the indoor space
Effects of Acute Exercise and Chronic Exercise on the Liver Leptin-AMPK-ACC Signaling Pathway in Rats with Type 2 Diabetes
Aim. To investigate the effects of acute and chronic exercise on glucose and lipid metabolism in liver of rats with type 2 diabetes caused by a high fat diet and low dose streptozotocin (STZ). Methods. Animals were classified into control (CON), diabetes (DC), diabetic chronic exercise (DCE), and diabetic acute exercise (DAE) groups. Results. Compared to CON, the leptin levels in serum and liver and ACC phosphorylation were significantly higher in DC, but the levels of liver leptin receptor, AMPKα1/2, AMPKα1, and ACC proteins expression and phosphorylation were significantly lower in DC. In addition, the levels of liver glycogen reduced significantly, and the levels of TG and FFA increased significantly in DC compared to CON. Compared to DC, the levels of liver AMPKα1/2, AMPKα2, AMPKα1, and ACC phosphorylation significantly increased in DCE and DAE. However, significant increase of the level of liver leptin receptor and glycogen as well as significant decrease of the level of TG and FFA were observed only in DEC. Conclusion. Our study demonstrated that both acute and chronic exercise indirectly activated the leptin-AMPK-ACC signaling pathway and increased insulin sensitivity in the liver of type 2 diabetic rats. However, only chronic and long-term exercise improved glucose and lipid metabolism of the liver
Effects of Dietary Protein and Lipid Levels on Growth, Metabolism, Antioxidative Capacity, and Fillet Quality of Adult Triploid Rainbow Trout Farmed in Net Cage
The research is aimed at investigating the effects of dietary protein and lipid levels on adult triploid rainbow trout growth performance, feed utilization, digestive and metabolic enzyme activities, antioxidative capacity, and fillet quality. Nine diets containing three dietary protein levels (DP) (300, 350, and 400 g kg-1) and three dietary lipid levels (DL) (200, 250, and 300 g kg-1) were prepared using a 3×3 factorial design. In freshwater cages, 13,500 adult female triploid rainbow trout (3.2±0.1 kg) were cultured for 77 days. Triplicate cages (500 fish per cage) were used as repetitions of each experimental diet. The findings revealed that as DP increased to 400 g kg-1 and DL raised to 300 g kg-1, the weight gain ratio (WGR) elevated significantly (P<0.05). However, when DP≥350 g kg-1, WGR was similar in the DL250 and DL300 groups. As DP raised to 350 g kg-1, the feed conversion ratio (FCR) notably decreased (P<0.05). In the DP350DL300 group, lipids had a protein-sparing impact. High DP diet (400 g kg-1) generally improved fish health status by increasing antioxidant capacity in the liver and intestine. A high DL diet (300 g kg-1) showed no harmful effect on hepatic health based on plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and antioxidant capacity in the liver. For fillet quality, a high DP diet could increase fillet yield, improve fillet hardness, springiness, and water-holding capacity values, and inhibit the production of off-flavors caused by n-6 fatty acids. A high DL diet could increase odor intensity, and EPA, DHA, and n-3 fatty acid concentrations decrease the thrombogenicity index value. The maximum fillet redness value was discovered in the DP400DL300 group. Overall, for adult triploid rainbow trout (≥3 kg), the minimum recommended DP and DL according to growth performance were 400 and 250 g kg-1, respectively; DP and DL based on feed utilization were 350 and 200���g kg-1, respectively; DP and DL based on fillet quality were 400 and 300 g kg-1, respectively
Enantioselective Bromocyclization of Olefins Catalyzed by Chiral Phosphoric Acid
A chiral phosphoric acid catalyzed enantioselective bromocyclization of olefins is described. Various <i>cis</i>-, <i>trans</i>-, or trisubstituted Îł-hydroxy-alkenes and Îł-amino-alkenes can cyclize under the reaction conditions to give optically active 2-substituted tetrahydrofurans and tetrahydropyrroles in up to 91% ee