Supplementing the early diet of broilers with soy protein concentrate can improve intestinal development and enhance short-chain fatty acid-producing microbes and short-chain fatty acids,especially butyric acid

Background:Research on nutrition in early-life commonly focuses on the maturation of the intestine because the intestinal system is crucial for ensuring continued growth.To explore the importance of early nutrition regulation in animals,soy protein concentrate(SPC)was added to the early diet of broilers to investigate its effects on amino acid digestibility,intestinal development,especially intestinal microorganisms,and broiler metabolites.A total of 192 oneday-old Arbor Acres(AA)male broilers were randomly assigned to two experimental treatments with 8 replicates of 12 birds.The control group was fed a basal diet(control),and the treatment group was fed a basal diet supplemented with 12%SPC(SPC12)during the first 10 d(starter phase).From d 11 to 21(grower phase)and d 22 to 42(finisher phase),a basal diet was fed to both treatment groups.Results:SPC reduced the pH value and acid-binding capacity of the starter diet(P<0.05,d 10);SPC in the early diet enhanced the gizzard weight(P<0.05,d 10 and d 42)and the ileum weight(P<0.05,d 10)and decreased the weight and length of the jejunum(P<0.05,d 10)and the relative length of the duodenum and jejunum(P<0.05,d 10).At the same time,SPC enhanced villus height(P<0.05,d 10)and muscle thickness in the jejunum and ileum(P<0.05,d 10)and increased the number of goblet cells in the duodenum(P<0.05,d 10).Meanwhile,SPC increased the Chao1 index and the ACE index(P<0.05,d 10)and altered the composition of caecal microflora at d 10.SPC also increased the relative abundance of Alistipes,Anaerotruncus,Erysipelatoclostridium,Intestinimonas and Flavonifractor bacteria(P<0.05,d 10).At the same time,the concentrations of caecal butyric acid and total short-chain fatty acids(SCFAs)were also increased in the SPC12 group(P<0.05,d 10).Conclusions:In summary,the results showed that supplementing the starter diet of broilers with SPC has a significant effect on the early development of the intestine and the microflora.

不同温度下天然橡胶/聚酯纤维界面的黏结失效

采用松香树脂作为增黏剂,制备了天然橡胶/聚酯纤维复合材料,并对其进行了3种不同温度的热老化处理,重点考察了经过不同温度的热老化处理后,使用H抽出法和扫描电镜观察法分析了复合材料的失效模式。结果表明,经过不同温度的热老化处理后,由于应力分布不同,出现了3种不同的失效模式:在110℃时,复合材料失效主要是橡胶/纤维的界面脱黏;在125℃时,复合材料同时发生界面脱黏和橡胶基体失效;在180℃时,复合材料主要发生橡胶基体失效。X射线光电子能谱测试结果显示,经过高温热老化后,橡胶表面的含氧官能团明显增加。

Real-Time Detection of Cracks on Concrete Bridge Decks Using Deep Learning in the Frequency Domain

This paper presents a vision-based crack detection approach for concrete bridge decks using an integrated one-dimensional convolutional neural network(1D-CNN)and long short-term memory(LSTM)method in the image frequency domain.The so-called 1D-CNN-LSTM algorithm is trained using thousands of images of cracked and non-cracked concrete bridge decks.In order to improve the training efficiency,images are first transformed into the frequency domain during a preprocessing phase.The algorithm is then calibrated using the flattened frequency data.LSTM is used to improve the performance of the developed network for long sequence data.The accuracy of the developed model is 99.05%,98.9%,and 99.25%,respectively,for training,validation,and testing data.An implementation framework is further developed for future application of the trained model for large-scale images.The proposed 1D-CNN-LSTM method exhibits superior performance in comparison with existing deep learning methods in terms of accuracy and computation time.The fast implementation of the 1D-CNN-LSTM algorithm makes it a promising tool for real-time crack detection.

A Fast and Accurate LEO Satellite-Based Direct Position Determination Assisted by TDOA Measurements

This paper focuses on the trusted vessel position acquisition using passive localization based on the booming low-earth-orbit(LEO) satellites. As the high signal-to-noise ratio(SNR) reception cannot always be guaranteed at LEO satellites, the recently developed direct position determination(DPD)is adopted. For LEO satellite-based passive localization systems, an efficient DPD is challenging due to the excessive exhaustive search range leading from broad satellite coverage. In order to reduce the computational complexity, we propose a time difference of arrival-assisted DPD(TA-DPD) which minimizes the searching area by the time difference of arrival measurements and their variances. In this way, the size of the searching area is determined by both geometrical constraints and qualities of received signals, and signals with higher SNRs can be positioned more efficiently as their searching areas are generally smaller.Both two-dimensional and three-dimensional passive localization simulations using the proposed TA-DPD are provided to demonstrate its efficiency and validity. The superior accuracy performance of the proposed method, especially at low SNRs conditions, is also verified through the comparison to conventional two-step methods. Providing a larger margin in link budget for satellite-based vessel location acquisition,the TA-DPD can be a competitive candidate for trusted marine location service.

Probiotic Escherichia coli Nissle 1917 protect chicks from damage caused by Salmonella enterica serovar Enteritidis colonization

As a foodborne pathogen of global importance,Salmonella enterica serovar Enteritidis(S.Enteritidis)is a threat to public health that is mainly spread by poultry products.Intestinal Enterobacteriaceae can inhibit the colonization of S.Enteritidis and are regarded as a potential antibiotic substitute.We investigated,in chicks,the anti-S.Enteritidis effects of Escherichia coli(E.coli)Nissle 1917,the most wellknown probiotic member of Enterobacteriaceae.Eighty 1-d-old healthy female AA broilers were randomly divided into 4 groups,with 20 in each group,namely the negative control(group P),the E.coli Nissle 1917-treated group(group N),the S.Enteritidis-infected group(group S)and the E.coli Nissle1917-treated and S.Enteritidis-infected group(group NS).From d 5 to 7,chicks in groups N and NS were orally gavaged once a day with E.coli Nissle 1917 and in groups P and S were administered the same volume of sterile PBS.At d 8,the chicks in groups S and NS were orally gavaged with S.Enteritidis and in groups P and N were administered the same volume of sterile PBS.Sampling was conducted 24 h after challenge.Results showed that gavage of E.coli Nissle 1917 reduced the spleen index,Salmonella loads,and inflammation(P<0.05).It improved intestinal morphology and intestinal barrier function(P<0.05).S.Enteritidis infection significantly reduced mRNA expression of angiotensin-converting enzyme 2(ACE2)and solute carrier family 6-member 19(SLC6A19)in the cecum and the content of Gly,Ser,Gln,and Trp in the serum(P<0.05).Pretreatment with E.coli Nissle 1917 yielded mRNA expression of ACE2and SLC6A19 in the cecum and levels of Gly,Ser,Gln,and Trp in the serum similar to that of uninfected chicks(P<0.05).Additionally,E.coli Nissle 1917 altered cecum microbiota composition and enriched the abundance of E.coli,Lactobacillales,and Lachnospiraceae.These findings reveal that the probiotic E.coli Nissle 1917 reduced S.Enteritidis infection and shows enormous potential as an alternative to antibiotics.

An Unmanned Aerial Vehicle Flight Formation for Enhanced Emergency Communication Based on Conformal Antenna Design

Benefiting from the inherent superiorities in flexibility and mobility,the use of unmanned aerial vehicles(UAVs)as flying base stations for wireless coverage has been of significant interest,especially for rescue services.This work concerns the reliable emergency communication based on commercial micro-sized UAVs due to their high availability and low cost.To decrease the weight overloads and to improve the power efficiency,a UAV body conformal and omnidirectional antenna is first presented based on the characteristic mode analysis.To extend the wireless coverage and to improve the communication quality of the UAV network,a UAV flight formation is then proposed and analyzed.In addition,the propagation analyses for the proposed UAV transmitter designs are performed in a realistic hilly canyon region.Simulations and comparisons are presented to demonstrate the effectiveness of the proposed designs in emergency communications and performance enhancement through the UAV flight formation.