Modelling vibratory roller–soil system dynamics using discrete element method

A simple yet useful implementation of lumped-parameter models using the discrete element method is discussed in this paper. Lumped-parameter models are often used in the modelling of vibratory roller-soil systems owing to their ability to capture the essential features observed during roller-soil vibrations. In order to investigate the system behaviour in the event of a decoupling (loss of contact between the drum and the soil), two conditions pertaining to the transition between the contact and non-contact phases are compared in the light of simulation results. The results demonstrate significant differences in the roller-soil system behaviour based on operating conditions. One particular case provides an unrealistic estimate of the contact force, and thus may lead to an incorrect prediction of the system dynamics. Another solution, however, provides a reasonable estimate of the system dynamics and is recommended herein

Holiday Destination Choice Behavior Analysis Based on AFC Data of Urban Rail Transit

For urban rail transit, the spatial distribution of passenger flow in holiday usually differs from weekdays. Holiday destination choice behavior analysis is the key to analyze passengers’ destination choice preference and then obtain the OD (origin-destination) distribution of passenger flow. This paper aims to propose a holiday destination choice model based on AFC (automatic fare collection) data of urban rail transit system, which is highly expected to provide theoretic support to holiday travel demand analysis for urban rail transit. First, based on Guangzhou Metro AFC data collected on New Year’s day, the characteristics of holiday destination choice behavior for urban rail transit passengers is analyzed. Second, holiday destination choice models based on MNL (Multinomial Logit) structure are established for each New Year’s days respectively, which takes into account some novel explanatory variables (such as attractiveness of destination). Then, the proposed models are calibrated with AFC data from Guangzhou Metro using WESML (weighted exogenous sample maximum likelihood) estimation and compared with the base models in which attractiveness of destination is not considered. The results show that the ρ2 values are improved by 0.060, 0.045, and 0.040 for January 1, January 2, and January 3, respectively, with the consideration of destination attractiveness

综合护理干预提高慢性乙型病毒性肝炎自我保健行为能力

Objectives: To explore suitable long-term antiviral therapy and comprehensive nursing intervention to patients with chronic hepatitis B system. Methods: To treat 136 cases of chronic hepatitis B patients with comprehensive nursing intervention and to investigate their regular medication situation, bad habits, self-observation and illness review visits before the intervention and after one month, three months and six months. Results: Regular medication situation, bad habits, self-observation and illness review visits of the patients who were treated with comprehensive nursing intervention have improved, and differences were statistically significant (P <0.05).Conclusion: Comprehensive nursing intervention can improve compliance, rehabilitation, knowledge level and life quality of the hepatitis B patients who suffered from long-term medication treatment.目的 探讨一种适合长期抗病毒治疗的慢性乙型病毒性肝炎患者的系统、统合的护理干预措施。方法 对136例慢性乙型病毒性肝炎初治患者进行综合护理干预，观察干预前、干预后1个月、3个月、半年时患者的规律服药情况、改变不良生活习惯、正确疾病自我观察及坚持疾病复查与回访等情况。结果 通过综合护理干预后患者规律服药情况、改变不良生活习惯、正确疾病自我观察及坚持疾病复查与回访等情况比较差异均有明显的统计学意义（P<0.05）。结论 对于需长期服药治疗的慢性乙型病毒性肝炎患者，通过向患者及家属开展系统的综合性的护理干预，可以提高患者治疗依从性，促进患者康复，提高患者治疗慢性乙型病毒性肝炎的知识掌握程度，改善生活质量

Synergetic Effect of Yihuo Qingyi Decoction () and Recombinant Staphylokinase in Treatment of Severe Acute Pancreatitis of Rats

ObjectiveTo investigate the effect of recombinant staphylokinase (r-Sak) and the Chinese medicine Yihuo Qingyi Decoction (Herbal decoction for severe acute pancreatitis) in the treatment of the severe acute pancreatitis (SAP) in rats, and to observe the synergistic effect of the two.MethodsOne hundred and sixty-two adult male SD rats with the body mass of 250–280 g were randomly divided into the following 5 groups: sham operation group (n=18), control group (n=36), Yihuo Qingyi Decoction treatment group (n=36), r-Sak treatment group (n=36), and Yihuo Qingyi Decoction plus r-Sak treatment group (n=36). The SAP ratmodel was prepared by retrograde injection of 5% sodium taurocholate into the cholangiopancreatic duct. Two days before modeling, Yihuo Qingyi Decoction was intragastrically administrated, and r-Sak was intraperitoneally injected. The survival rate within 18 h after modeling was determined. The pancreatic blood flow, the weight of ascites, and the serum amylase and lipase were investigated at 6 h, 12 h, and 18kh after modeling, and the pancreatic tissue was examined under light microscopy to see its pathological change.ResultsThe 18 h survival count of group A,B,C,D and E rats was 9,2,6,7 and 8 respectively. After r-Sak and Yihuo Qingyi Decoction intervention, the serum amylase and lipase and the weight of ascites were significantly decreased, especially in group E.18 h after modeling, the level of the serum amylase and lipase and the weight of ascites in group E was 1 100±118 U·L−1,1 000±150 U·L−1 and 13.40±1.80 g respectively, obviously lower than that of group B (P<0.05). After SAP was induced, the pancreatic blood flow showed a tendency to decrease, but the decrease extent in the treatment groups was smaller than that in the control group.18h after modeling, the pancreatic blood flow in group B and group E was 30.16±8.96 mL·100 g−1·min−1, and 129.10±42.58 mL·100 g−1·min−1 respectively, there was significant difference (P<0.05). The pathological change of the pancreatic tissue was alleviated in the treatment groups.ConclusionBoth r-Sak and Yihuo Qingyi Decoction play a beneficial role in the treatment of rat SAP and there is a synergistic effect between the two

Mtmr8 is essential for vasculature development in zebrafish embryos

<p>Abstract</p> <p>Background</p> <p>Embryonic morphogenesis of vascular and muscular systems is tightly coordinated, and a functional cooperation of Mtmr8 with PI3K in actin filament modeling and muscle development has been revealed in zebrafish. Here, we attempt to explore the function of Mtmr8 in vasculature development parallel to its function in muscle development.</p> <p>Results</p> <p>During early stage of somitogenesis, <it>mtmr8 </it>expression was detected in both somitic mesodem and ventral mesoderm. Knockdown of <it>mtmr8 </it>by morpholino impairs arterial endothelial marker expression, and results in endothelial cell reduction and vasculogenesis defects, such as retardation in intersegmental vessel development and interruption of trunk dorsal aorta. Moreover, <it>mtmr8 </it>morphants show loss of arterial endothelial cell identity in dorsal aorta, which is effectively rescued by low concentration of PI3K inhibitor, and by over-expression of <it>dnPKA </it>mRNA or <it>vegf </it>mRNA. Interestingly, <it>mtmr8 </it>expression is up-regulated when zebrafish embryos are treated with specific inhibitor of Hedgehog pathway that abolishes arterial marker expression.</p> <p>Conclusion</p> <p>These data indicate that Mtmr8 is essential for vasculature development in zebrafish embryos, and may play a role in arterial specification through repressing PI3K activity. It is suggested that Mtmr8 should represent a novel element of the Hedgehog/PI3K/VEGF signaling cascade that controls arterial specification.</p

2-Chloro­methyl-2,3-dihydro­thieno[3,4-b][1,4]dioxine

In the mol­ecule of the title compound, C7H7ClO2S, the six-membered ring adopts a twisted conformation. In the crystal structure, weak inter­molecular C—H⋯O hydrogen bonds link the mol­ecules. There is also a weak C—H⋯π inter­action

SHEARING BEHAVIOR OF STRUCTURAL INSULATED PANEL WALL SHELLED WITH BAMBOO SCRIMBER

In this study, shearing behavior of a structural insulated panel (SIP) wall, which consisted of a Styrofoam core board, shell panel of bamboo scrimber, and frame of Spruce–Pine–Fir dimension lumber, was tested under monotonic and cyclic loads. Results showed that the SIP wall failed at similar positions under two loading modes, although more serious destruction occurred under cyclic than monotonic load. There was a linear relationship between load and displacement at the initial loading stage, which indicated that the wall worked under the elastic state. At a later loading stage, bearing capacity and rigidity decreased as a result of wall slip. Shearing strength under monotonic and cyclic loads was 20.0 and 15.8 kNm-1, respectively, which met the requirement of the standard code for design of timber structures. Energy consumption of the SIP wall covered with bamboo scrimber was 11,556.6 Jm-1