253 research outputs found

    Research on Chloride Penetration Resistance of Hybrid Fiber Reinforced Self-Compacting Concrete

    Get PDF
    The properties of chloride penetration of hybrid fiber reinforced self-compacting concrete (SCC) were investigated in this study. The results show that, the chloride penetration resistance of concrete can be improved by single incorporation either carbon or cellulose fibers. The concrete chloride diffusion coefficient DRCM of 12-cm length carbon SCC with fiber content of 1.7 kg/m3, 2.72 kg/m3, and 3.4 kg/m3 decreases by 10.3%, 25.5%, and 18.2% compared to reference concrete without any fibers, respectively. Moreover, the concrete chloride diffusion coefficient DRCM of cellulose SCC with fiber content of 1.2 kg/m3, 1.6 kg/m3, and 2.0 kg/m3 decreases by 18.8%, 22.4%, and 26.7% compared to reference concrete, respectively. Based on the results of orthogonal experimental design, the chloride diffusion coefficients DRCM of hybrid fiber reinforced SCC are listed in order of importance, as follows: length of carbon fiber \u3e content of carbon fiber \u3e content of cellulose fiber; furthermore, the hybrid of 2.72-kg/m3 carbon fiber with length of 12mm and 2.0-kg/m3 cellulose fiber exhibits the most significant effect on chloride diffusion coefficients DRCM of SCC

    A shorter loop in RouxY hepatojejunostomy reconstruction for choledochal cysts is equally effective: preliminary results of a prospective randomized study. J Pediatr Surg

    Get PDF
    Abstract Background: Conventionally, an adult's standard of a 40-cm loop is adopted in Roux-Y hepatojejunostomy (RYHJ) in choledochal cyst (CDC) in children, irrespective of patient size. The redundant length of the jejunal limb may lead to complications. We compared the outcome of an individualized short Roux loop with the standard loop length in RYHJ in children with CDC. Methods: Two hundred eighteen children with CDC undergoing laparoscopic RYHJ were prospectively randomized into 2 groups: (1) conventional group (CG; n = 108) where a standard 35-40 cm Roux-loop length was used regardless of the child's size and (2) short loop group (SLG; n = 110) in which the Roux-loop length was based on the distance between hepatic hilum and umbilicus. Ultrasonography, upper gastrointestinal contrast studies, and laboratory tests were conducted during the follow-up period. Results: The mean Roux-loop length of SLG was significantly shorter than that of CG (Student t test, P b .05). There was no significant difference between the 2 groups in age, operative blood loss, operative time, postoperative hospital stay, and duration of drainage. In CG, 2 of (1.8%) 108 patients developed Roux-loop obstruction, whereas none was detected in SLG (0%). Mild reflux was detected in 2 CG patients and 1 SLG patient 1 month postoperatively, all of which subsided 6 months later. No episodes of cholangitis were observed in either group. Conclusions: An individualized short Roux-loop length in RYHJ is as effective as the conventional Roux-loop length

    GRID: Scene-Graph-based Instruction-driven Robotic Task Planning

    Full text link
    Recent works have shown that Large Language Models (LLMs) can promote grounding instructions to robotic task planning. Despite the progress, most existing works focused on utilizing raw images to help LLMs understand environmental information, which not only limits the observation scope but also typically requires massive multimodal data collection and large-scale models. In this paper, we propose a novel approach called Graph-based Robotic Instruction Decomposer (GRID), leverages scene graph instead of image to perceive global scene information and continuously plans subtask in each stage for a given instruction. Our method encodes object attributes and relationships in graphs through an LLM and Graph Attention Networks, integrating instruction features to predict subtasks consisting of pre-defined robot actions and target objects in the scene graph. This strategy enables robots to acquire semantic knowledge widely observed in the environment from the scene graph. To train and evaluate GRID, we build a dataset construction pipeline to generate synthetic datasets in graph-based robotic task planning. Experiments have shown that our method outperforms GPT-4 by over 25.4% in subtask accuracy and 43.6% in task accuracy. Experiments conducted on datasets of unseen scenes and scenes with different numbers of objects showed that the task accuracy of GRID declined by at most 3.8%, which demonstrates its good cross-scene generalization ability. We validate our method in both physical simulation and the real world

    Immune Responses in Mice Immunized with Mastitis Multiple Vaccines Using Different Adjuvants

    Get PDF
    Background: Bovine mastitis, a serious disease associated with both high incidence and significant economic losses, posing a major challenge to the global dairy industry. The development of vaccines for protection from new infections by mastitis pathogens is of considerable interest to the milk production industry. Vaccination is a common and easy strategy for the control of infectious diseases, and the adjuvants used in the formulation is a critical factor for vaccine efficacy improvement. The main objective of the present study was to evaluate three different adjuvants for their ability to enhance immune responses of mice that vaccinated with Bovine Mastitis Multiple Vaccine.Materials, Methods & Results: The thymus and spleen index, the phagocytic ability of macrophage and the serum antibody levels of mice were detected after vaccination, respectively. The results showed that the thymus index, spleen index, and the phagocytic ability of macrophage of mice in Aluminum group exhibited a significant higher level (P < 0.05) compared with those in the control groups. The difference of the serum antibody levels was significant (P < 0.05) between experimental groups and control group after vaccination. The serum antibody concentration of mice in FIA group was higher compared with other groups and had a longer duration. The antibody concentration of mice in France 206 oil group can not increase as fast as the antibody concentration of Aluminum group, but it can last a longer time at a high level. In conclusion, multiple vaccines mixed with three different adjuvants could enhance the immunity of mice and Freund’s incomplete adjuvant is the best choice for this vaccine.Discussion: Adjuvants play an important role in increasing the efficacy of a number of different vaccines. In this study, three kinds of adjuvants (Aluminum hydroxide, France 206 oil and FIA) were evaluated for their adjuvant effects for multiple vaccine of bovine mastitis in mice and aluminum hydroxide did best as the vaccine adjuvant from the results. Aluminum hydroxide is a universally accepted adjuvant for both human and veterinary vaccines. The goal of vaccination is to generate strong immune response providing protection against infection for a time. Different protective effects will usually obtained by different adjuvants even use same antigen. In this work, FIA, Alum and 206 oil were chosen as adjuvants for inactivated antigens of Streptococcus agalactiae, Streptococcus dysgalactiae and Staphylococcus aureus. The results showed that there was a significantly higher antibody levels in vaccinated mice compared with those in control group. In addition, the mice in France 206 oil and FIA group performed a higher antibody levels and stronger immunity than mice in Aluminum hydroxide groups. These findings suggest that Freund’s incomplete adjuvant (FIA) would be the best candidate as the adjuvant for mastitis multiple vaccines investigated in this study

    Distribution of Serotypes, Antimicrobial Resistance and Virulence Genes among Streptococcus agalactiae Isolated from Bovine in China

    Get PDF
    Background: Bovine mastitis, a global disease that is responsible for large economic losses each year due to lower milk yield and reduced milk quality. In some countries, especially in China, Streptococcus agalactiae has become one of the most frequently detected pathogen. Antibiotic treatment and vaccine immunization are important strategies for the control of infectious diseases. The main objective of the present study was to evaluate distribution of bovine mastitis pathogens and antimicrobial resistance of S. agalactiae, and contribute to the treatment of bovine mastitis.Materials, Methods & Results:Clinical mastitis samples (n= 1,122) were collected from 27 dairy farms located in 15 different provinces of China during 2012-2018. Thepathogens were identified by 16S rDNA method. Antimicrobial susceptibility was assessed by disc diffusion method. Molecular characteristics was distinguished based on PCR. The results showed that the main pathogens were Streptococcus agalactiae (n= 324, 26.2%), Escherichia coli (n= 287, 23.2%), and Staphylococcus aureus (n= 131, 10.6%). The serotypes of Streptococcus agalactiae were serotype II (53.6%), Ia (44 %) and VII (1.2%), respectively. Streptococcus agalactiae were resistant to kanamycin (93.8%), gentamicin (49.4%), vancomycin (49.4%), tetracycline (35.8%), clindamycin (34.6%) and erythromycin (32.1%). The main resistance genes were ermA (53.1%) and ermB (85.2%). Resistance to erythromycin was attributed to the genes ermA (P < 0.05) and resistance to tetracycline was attributed to the genes tetK, tetM, tetO (P < 0.01). The virulence genes scpB (81.4%), cyl (100%), glnA (76.6%), cfb (98.8%), hylB (98.8%), scaA (69.1%) were detected in almost all isolates.Discussion: In the present study, Streptococcus agalactiae, Escherichia coli and Staphylococcus aureus were the pathogens isolated most frequently from clinical mastitis. In the case of S. agalactiae, we performed capsular serotyping of isolates. As a result, serotype II (53.6%), Ia (44 %) and VII (1.2%) were detected whichrevealed variation in the distinct geographical areas. We found that serotypes (Ia and II) and β-hemolytic have significant correlation (P < 0.01) in all isolated strains. We made an assumption that either in processes of capsular and haemolytic appearance effected the expression of another. The unclear mechanism remains to be resolved in the future. Penicillin was recommended as a preferred antibiotic for the treatment of both human and bovine S. agalactiae infection. In the present study, resistance to erythromycin and clindamycin were observed in 32% and 34.6% of our strains, respectively. The results indicated that the ermB gene was most frequent among the erythromycin-resistant S. agalactiae. However, we found that the susceptibility to erythromycin and gene ermA have a significant interaction, while susceptibility to erythromycin and gene ermB have a not significant interaction by analyzing the relationship of phenotypic and genotypic resistance. The severity of S. agalactiae infections may be determined by various virulence factors. Surface enzyme ScpB, a C5a peptidase, encode by scpB gene, could promote bacterial invasion of epithelial cells by attenuating recruitment of polymorphonuclear leukocytes to the site of infection. In the present study, the scpB gene was found in 81.4% of all strains. The results suggested the cyl, cfb, hylB and scpB genes may play an important role in the virulence of Streptococcus agalactiae pathogens

    Prediction of the 20-year incidence of diabetes in older Chinese: Application of the competing risk method in a longitudinal study

    Get PDF
    The competing risk method has become more acceptable for time-to-event data analysis because of its advantage over the standard Cox model in accounting for competing events in the risk set. This study aimed to construct a prediction model for diabetes using a subdistribution hazards model

    Microstructure and structural modulation of lutetium dihydride LuH2 as seen via transmission electron microscopy

    Full text link
    Structural investigations conducted using transmission electron microscopy (TEM) on LuH2 synthesized under atmospheric pressure (AP-LuH2) and nitrogen-doped LuH2 synthesized under high pressure (HP-LuH2) have revealed numerous microstructural phenomena. Both materials show a clear superstructure modulation with wave vector, q^* = 1/4 (2-20), and this modulation can be well interpreted by the displacements of Lu atoms. Further investigations on the nitrogen-doped HP-LuH2 materials reveal the appearance of high-density antiphase boundaries, in particular, domain walls of a few atomic layer thickness without structural modulation can be observed, suggesting possible interface properties could be detected in this system. In-situ TEM observations of AP-LuH2 suggest that no evident structural phase transition occurs between 94 K and 673 K.Comment: 8 pages, 7 figure

    A competing-risk-based score for predicting twenty-year risk of incident diabetes: the Beijing Longitudinal Study of Ageing study

    Get PDF
    Few risk tools have been proposed to quantify the long-term risk of diabetes among middle-aged and elderly individuals in China. The present study aimed to develop a risk tool to estimate the 20-year risk of developing diabetes while incorporating competing risks. A three-stage stratification random-clustering sampling procedure was conducted to ensure the representativeness of the Beijing elderly. We prospectively followed 1857 community residents aged 55 years and above who were free of diabetes at baseline examination. Sub-distribution hazards models were used to adjust for the competing risks of non-diabetes death. The cumulative incidence function of twenty-year diabetes event rates was 11.60% after adjusting for the competing risks of non-diabetes death. Age, body mass index, fasting plasma glucose, health status, and physical activity were selected to form the score. The area under the ROC curve (AUC) was 0.76 (95% Confidence Interval: 0.72–0.80), and the optimism-corrected AUC was 0.78 (95% Confidence Interval: 0.69–0.87) after internal validation by bootstrapping. The calibration plot showed that the actual diabetes risk was similar to the predicted risk. The cut-off value of the risk score was 19 points, marking mark the difference between low-risk and high-risk patients, which exhibited a sensitivity of 0.74 and specificity of 0.65
    • …
    corecore