Investigation of bio-aerosol dispersion in a tunnel-ventilated poultry house

Bio-aerosol concentrations in poultry houses must be controlled to provide adequate air quality for both birds and workers. High concentrations of airborne bio-aerosols would affect the environmental sustainability of the production and create environmental hazards to the surroundings via the ventilation systems. Previous studies demonstrate that several factors including the age of the birds, the housing configuration, the humidity and temperature would strongly affect the indoor concentration of bio-aerosols. However, limited studies are performed in the literature to investigate the bio-aerosol dispersion pattern inside poultry buildings. In order to fill a gap of the understanding of the bio-aerosol dispersion behavior, experimental measurements of the indoor bio-aerosol distribution are performed in a tunnel-ventilated poultry house in this paper. Meanwhile a three-dimensional computational fluid dynamics (CFD) model is built and validated to further investigate the effect of flow pattern, turbulence and vortex on the dispersion and deposition of the bio-aerosols. Furthermore, bio-aerosols with various diameters are also examined in the CFD model. It is found that higher concentrations of bio-aerosols are detected at the rear part of the house and strong turbulent flow resulting from the ventilation inlets enhances the diffusion and dispersion of bio-aerosols. Local vortex or disturbed flow is responsible for higher local concentration due to the re-suspension of settled bio-aerosols, which suggests that careful attentions should be paid to these locations during cleaning and disinfection. Results from present study contribute to the optimization of design and operation of the poultry houses from the standing point of reducing airborne bio-aerosol concentrations

Digital Twin Brain: a simulation and assimilation platform for whole human brain

In this work, we present a computing platform named digital twin brain (DTB) that can simulate spiking neuronal networks of the whole human brain scale and more importantly, a personalized biological brain structure. In comparison to most brain simulations with a homogeneous global structure, we highlight that the sparseness, couplingness and heterogeneity in the sMRI, DTI and PET data of the brain has an essential impact on the efficiency of brain simulation, which is proved from the scaling experiments that the DTB of human brain simulation is communication-intensive and memory-access intensive computing systems rather than computation-intensive. We utilize a number of optimization techniques to balance and integrate the computation loads and communication traffics from the heterogeneous biological structure to the general GPU-based HPC and achieve leading simulation performance for the whole human brain-scaled spiking neuronal networks. On the other hand, the biological structure, equipped with a mesoscopic data assimilation, enables the DTB to investigate brain cognitive function by a reverse-engineering method, which is demonstrated by a digital experiment of visual evaluation on the DTB. Furthermore, we believe that the developing DTB will be a promising powerful platform for a large of research orients including brain-inspiredintelligence, rain disease medicine and brain-machine interface.Comment: 12 pages, 11 figure

Computational Fluid Dynamics aided investigation and optimization of a tunnel-ventilated poultry house in China

Ventilation system is crucial for poultry houses to control the indoor climate and air quality. The tunnel ventilation system is widely applied for large-scale poultry buildings in China but only limited scientific researches regarding the flow pattern, temperature distribution and design criteria are available in the literature. Thanks to the fast development of computer technology, Computational Fluid Dynamics (CFD) techniques were used in present study to investigate the indoor air movement, air temperature and relatively humidity. A three-dimensional CFD model was built according to the real dimensions of a laying hen house and the model was validated by comparing the simulation results with the field measurements at 30 positions. Meanwhile, statistical analysis was performed to determine the differences between different boundary conditions regarding the agreement between measured and CFD simulated results. Optimization of air inlet configurations was performed by using the validated CFD model and it was found that the uniformity of indoor air movement could prevent excessive local convective heat losses and reduce the temperature at the end of the house. Furthermore, the air inlets placed at the middle of the side wall could significantly reduce the high temperature expected at the end of the building without using extra energy, which is especially important for large-scale poultry farms with long buildings. The performance of side-wall windows was also examined and preliminary guidance was provided to effectively regulate the indoor climate by using these windows with the help of environmental monitoring systems. The present study contributes to the understanding and design of the tunnel ventilation system used in poultry houses

Construction and verification of an environment and energy prediction model for Controlled Environment Housing

In order to satisfy the healthy growth and performance of livestock and poultry, a large amount of energy is often consumed in the production process of modern livestock and poultry breeding, which is used for automatic feeding management and regulation of breeding environment. In this study, based on the ISO 13790 5R1C equivalent resistance capacitance network computing model, using the henhouse heat balance, water balance, balance of gas (ammonia, carbon dioxide concentration) principle, we developed a simple closed loop control henhouse environment and energy consumption prediction model, Through on-site validation tests, the results show that the model is reliable, and it can assist the farmer for breeding planning, house-design process and increase environmental control and energy management efficiency

Association of Polymorphisms of Chicken Adipose Differentiation-related Protein Gene with Carcass Traits

Adipose differentiation-related protein (ADFP) plays an important role in regulating lipid storage and affecting body fat distribution. The objective of the current research was to identify the polymorphisms in chicken ADFP gene and their associations with carcass traits. We screened all coding sequence and part of introns (totally 2155bp) of the ADFP gene by using single strand conformation polymorphism method in individuals from Sanhuang chicken, Mountainous Black-bone chicken and a commercial crossbred chicken (totally 427 birds). Three novel single-nucleotide polymorphisms were found in intron 4 (SNP1), intron 5 (SNP2) and exon 8 (SNP3), respectively. The association analyses showed that genotypes of SNP1 were significantly associated with abdominal fat weight and percentage of abdominal fat (P<0.05), genotypes of SNP2 were significantly associated with breast muscle weight and percentage of abdominal fat (P<0.05), and the main haplotype/haplotypes combination (their frequencies were higher than 5%) were marginally significantly associated with breast muscle weight, abdominal fat weight, and percentage of abdominal fat (0.05<P<0.1). Haplotype H2 (A-C-A) was an advantageous haplotype for breast muscle weight and H5 (T-C-G) was an advantageous haplotype for weight and percentage of abdominal fat. Conversely, H3H3 (A-T-G/A-T-G) was a disadvantage haplotype combination for accumulation of abdominal fat. These results suggested that polymorphisms of ADFP gene were associated with carcass traits, especially with fatness traits. ADFP is a potential major gene or in close linkage disequilibrium with the QTL affecting fatness traits in chickens

A Low-Altitude Remote Sensing Inspection Method on Rural Living Environments Based on a Modified YOLOv5s-ViT

The governance of rural living environments is one of the important tasks in the implementation of a rural revitalization strategy. At present, the illegal behaviors of random construction and random storage in public spaces have seriously affected the effectiveness of the governance of rural living environments. The current supervision on such problems mainly relies on manual inspection. Due to the large number and wide distribution of rural areas to be inspected, this method is limited by obvious disadvantages, such as low detection efficiency, long-time spending, and huge consumption of human resources, so it is difficult to meet the requirements of efficient and accurate inspection. In response to the difficulties encountered, a low-altitude remote sensing inspection method on rural living environments was proposed based on a modified YOLOv5s-ViT (YOLOv5s-Vision Transformer) in this paper. First, the BottleNeck structure was modified to enhance the multi-scale feature capture capability of the model. Then, the SimAM attention mechanism module was embedded to intensify the model’s attention to key features without increasing the number of parameters. Finally, the Vision Transformer component was incorporated to improve the model’s ability to perceive global features in the image. The testing results of the established model showed that, compared with the original YOLOv5 network, the Precision, Recall, and mAP of the modified YOLOv5s-ViT model improved by 2.2%, 11.5%, and 6.5%, respectively; the total number of parameters was reduced by 68.4%; and the computation volume was reduced by 83.3%. Relative to other mainstream detection models, YOLOv5s-ViT achieved a good balance between detection performance and model complexity. This study provides new ideas for improving the digital capability of the governance of rural living environments

A Low-Altitude Remote Sensing Inspection Method on Rural Living Environments Based on a Modified YOLOv5s-ViT

The governance of rural living environments is one of the important tasks in the implementation of a rural revitalization strategy. At present, the illegal behaviors of random construction and random storage in public spaces have seriously affected the effectiveness of the governance of rural living environments. The current supervision on such problems mainly relies on manual inspection. Due to the large number and wide distribution of rural areas to be inspected, this method is limited by obvious disadvantages, such as low detection efficiency, long-time spending, and huge consumption of human resources, so it is difficult to meet the requirements of efficient and accurate inspection. In response to the difficulties encountered, a low-altitude remote sensing inspection method on rural living environments was proposed based on a modified YOLOv5s-ViT (YOLOv5s-Vision Transformer) in this paper. First, the BottleNeck structure was modified to enhance the multi-scale feature capture capability of the model. Then, the SimAM attention mechanism module was embedded to intensify the model’s attention to key features without increasing the number of parameters. Finally, the Vision Transformer component was incorporated to improve the model’s ability to perceive global features in the image. The testing results of the established model showed that, compared with the original YOLOv5 network, the Precision, Recall, and mAP of the modified YOLOv5s-ViT model improved by 2.2%, 11.5%, and 6.5%, respectively; the total number of parameters was reduced by 68.4%; and the computation volume was reduced by 83.3%. Relative to other mainstream detection models, YOLOv5s-ViT achieved a good balance between detection performance and model complexity. This study provides new ideas for improving the digital capability of the governance of rural living environments

Magnetization-induced optical rectification and inverse spin Hall effect for interfacial terahertz generation in metallic heterostructures

Metallic heterostructure as promising terahertz (THz) spintronic emitters has promoted the development of both spintronics and THz science. However, the underlying physics at the metallic interface, such as the nonlinear optical effect, remains unclear. Herein, we present interface magnetization induced THz generation from metallic heterostructure consisting of Heusler alloy CoFeMnSi (CFMS) and Pd thin films. THz generation is ascribed to 35% contribution from the magnetization-induced optical rectification (MOR) and 65% contribution from inverse spin Hall effect (ISHE) based on the pump polarization and sample azimuthal angle dependent measurement. Furthermore, the contribution ratio of the MOR decreases to 12% via lowering the CFMS grown temperature, which is due to the reduced crystalline quality and possible metal to semiconductor transformation in CFMS. Our results not only clarify MOR and ISHE in metallic heterostructure for the scientific field, but they also benefit THz source optimization for the technology field

Wetting characteristic and flow behavior of silicate binder at various sand particle-particle interfaces: Fine or coarse, circular or angular particles

This study presents an innovative investigation into the wetting characteristic and flow behavior of sand particles, which have different shapes, sizes, and textures, when they bonded with silicate binder. The results revealed that the apparent contact angles of fine and angular particles with the binder are higher than those of coarse and circular particles. In addition, after modifying the four systems with anionic surfactants, the equilibrium contact angles decreased by 42.8%, 26.7%, 26.5%, and 7%. These findings suggest that coarse and circular particles demonstrate stronger wetting properties with the binder compared to fine and angled particles. Additionally, the cohesion and internal friction angle of the wet sand mixture can be measured through the ring shear test. Moreover, the unconfined yield strength and main consolidation stress can be calculated using the Mohr Coulomb model to obtain the yield locus and quantify the flowability of the wet sand mixture. The yield trajectory of sand mixtures at specific consolidation stresses suggests that the most important factor affecting the flowability of wet sand particles is particle size distribution. Wet mixtures of coarse and circular particles exhibit lower cohesive forces, indicating higher fluidity

Study on Association of Single Nucleotide Polymorphism of MC3R and MC4R Genes with Carcass and Meat Quality Traits in Chicken

Body composition, fat deposition and meat quality are important traits in chickens. Melanocortin receptor (MCR) plays an important role in central melanocortin system (CMS) and muscle cells. The purpose of the present study was to analyze association of the MC3R and the MC4R genes with chicken carcass and meat quality traits. Using eight meat-type chicken populations constructed with 5 pure lines (developed from Chinese local breeds) and 3 crossbreeds (S01×D99, S01×S05, S01×S10), the association of 3 single nucleotide polymorphisms (SNP: MC3R-A1424G, MC4R-G923T and MC4R-C944T) of MC3R and MC4R gene with carcass and meat quality traits was studied. The results showed as follows: (1) the MC3R-A1424G genotypes were significantly associated with most carcass traits except for semi-eviscerated percentage and leg muscle percentage (LMP), the MC4R-G923T genotypes were significantly associated with live weight, carcass weight, leg muscle weight (LMW) and LMP, and the MC4R-C944T genotypes were not significantly associated with most carcass traits except for LMW and LMP; (2) to meat quality, the MC3R-A1424G genotypes significantly affected muscle crude protein (GP) value, and the allele A had positive additive effects on slaughter traits. The MC4R-G923T and the MC4R-C944T sites significantly affected muscle GP value and glutamic acid (Glu) value; (3) the haplotypes based on the 2 SNP of MC4R gene were also significantly associated with meat quality traits, but had no significant associations with carcass traits. The research built the base for further analysis on relation between genetic variation of MC3R and MC4R genes and the carcass and meat quality traits, and molecular marker's application in breeding