579 research outputs found

    Wilson Lines and Boundary Operators of BCFW Shifts

    Full text link
    Boundary operators are gauge invariant operators whose form factors correspond to boundary contributions of BCFW shifts. In gauge theory, the boundary operators contain infinite series, which are constrained by gauge symmetry. We compute the boundary operators of all possible BCFW shifts in Yang-Mills theory and QCD, and show that the infinite series can be elegantly organized into Wilson lines, which are natural building blocks for non-local gauge invariant operators. We comment on their connection to jet functions and gauge invariant off-shell amplitudes. We also verify our results by studying various BCFW shifts of four and five-point amplitudes.Comment: 28 pages, 5 figures, improve the writing and correct some typo

    Environmental taxes and the effects of partial privatization on environmental R&D, environment and welfare

    Get PDF
    This paper considers environmental R&D (ER&D) of clean technology for reducing pollutant emissions in a polluting mixed duopoly and analyzes partial privatization’s impacts on ER&D, environment and welfare. In the situation that environmental taxes are exogenously given, it finds that the impacts of privatization policy on ER&D and environment critically depend on the level of environmental damage. However, regardless of the marginal damage, an appropriate partial-privatization policy can increase social welfare. In addition, it also considers an endogenously determined optimal environmental tax and shows that if the marginal damage is high, partial privatization’s impacts on ER&D, environment and social welfare may be not the same as the exogenous environmental tax situatio

    Dynamic Analysis and Active Control of a Dielectric Elastomer Balloon Covered by a Protective Passive Layer

    Get PDF
    Dielectric elastomer (DE) balloons are intensively developed as sensors, actuators, and generators.  To ensure electrical safety, a DE balloon can be covered by an external passive layer. In this paper, the dynamic behaviours and active control for the DE balloon coupled with the passive layer are investigated. Based on the Hamilton’s principle, the dynamic model of the DE balloon covered by the passive layer is derived. With this coupled model, we demonstrate that three typical dynamic responses can appear and the transition among these dynamic behaviours can be achieved by altering the properties of the passive layer. The introduction of the passive layer is able to induce undesirable dynamic behaviours, which require to be controlled. Thus, we present two methods of control including proportional-derivative (PD) control and iterative learning control (ILC). We demonstrate that the undesirable dynamic responses can be effectively eliminated by the proposed methods of control. Particularly, control errors can be reduced by 2 or 3 orders of magnitude using the latter control method. We hope that the present analysis can improve the understanding of dynamic behaviours of a DE balloon covered by a passive layer and promote the control of undesirable dynamic responses

    Reprogramming of blood cells into induced pluripotent stem cells as a new cell source for cartilage repair

    Get PDF
    Characterization of hMSCs and hMSC-chondrogenic pellets. (a) Flow cytometric analysis of the hematopoietic markers (CD34, CD45) and MSC markers (CD73, CD105) in hMSCs. The proportion of CD73-expressing cells was 99.7 ± 0.63 %; The proportion of CD105-expressing cells was 98.7 ± 1.21 %. Values represent means ± SEM; n = 3. (b) Three-dimensional pellet culture of the hMSC-chondrogenic pellet. (c) Alcian blue staining and (d) toluidine blue staining of glycosaminoglycans and proteoglycans revealed the chondrocyte-type appearance in the hMSC-chondrogenic pellets. Scale bar = 100 μm. (e,f) Immunohistochemistry for type II and type X collagen. Scale bar = 100 μm. (TIF 8130 kb

    Correlation-induced symmetry-broken states in large-angle twisted bilayer graphene on MoS2

    Full text link
    Strongly correlated states are commonly emerged in twisted bilayer graphene (TBG) with magic-angle, where the electron-electron (e-e) interaction U becomes prominent relative to the small bandwidth W of the nearly flat band. However, the stringent requirement of this magic angle makes the sample preparation and the further application facing great challenges. Here, using scanning tunneling microscopy (STM) and spectroscopy (STS), we demonstrate that the correlation-induced symmetry-broken states can also be achieved in a 3.45{\deg} TBG, via engineering this non-magic-angle TBG into regimes of U/W > 1. We enhance the e-e interaction through controlling the microscopic dielectric environment by using a MoS2 substrate. Simultaneously, the bandwidth of the low-energy van Hove singularity (VHS) peak is reduced by enhancing the interlayer coupling via STM tip modulation. When partially filled, the VHS peak exhibits a giant splitting into two states flanked the Fermi level and shows a symmetry-broken LDOS distribution with a stripy charge order, which confirms the existence of strong correlation effect in our 3.45{\deg} TBG. Our result paves the way for the study and application of the correlation physics in TBGs with a wider range of twist angle

    An accidental household outbreak of paliperidone palmitate poisoning via pancake consumption in Lianyungang, China

    Get PDF
    Introduction: At 11:20 on 26 May 2018, a physician from Lianyungang No. 1 People’s Hospital, China, reported that six family members were being treated in the hospital with symptoms from an unknown cause. Methods: A case series for a food poisoning investigation and an environmental survey were conducted. The patients and their relatives were interviewed in person with a questionnaire contained on a digital tablet, and an investigation of the patients’ home was conducted in the presence of police officers. Probable case and confirmed case were defined to serve as a basis for identifying additional cases. Confirmed cases were defined as those probable cases in which blood, stool or vomitus specimens tested positive for paliperidone palmitate and/or its metabolites. A descriptive analysis was performed. Follow-up by telephone was conducted four months later. Results: There were six probable cases. The median age was 35 years (range: 5–76 years). The attack rate was 100% (n = 6/6) of persons who consumed a family dinner, and the hospitalization rate was also 100% (n = 6/6). The median period between exposure and symptom onset was two hours. The main symptoms included vomiting, nausea, drowsiness, dizziness and severe abdominal pain for adults, and vomiting and severe lethargy for children. An 8-year-old girl further showed changes in the ST segment of her electrocardiogram, and a 5-year-old boy showed QT prolongation. The poisoning substance was suspected to be paliperidone palmitate based on the patients’ symptoms and epidemiological findings

    Plant defense negates pathogen manipulation of vector behavior

    Get PDF
    1. Although many vector‐borne plant pathogens can alter vector behaviour to the pathogen\u27s benefit, how plants might counter such manipulation is unknown. 2. In the Tomato yellow leaf curl virus (‘TYLCV’)–Bemisia tabaci–tomato interaction, TYLCV‐mediated changes in Bemisia feeding improves viral uptake and transmission. We tested how jasmonic acid (‘JA’), a central regulator of plant antiherbivore defences, affected the ability of TYLCV to (A) manipulate Bemisia behaviour; and (B) infect plants. 3. Viruliferous Bemisia fed much more than virus‐free whiteflies on JA‐deficient plants, more than virus‐free whiteflies on controls, and similarly on high‐JA plants. 4. When TYLCV was transmitted via whiteflies, infection levels were lower in high‐JA plants relative to JA‐deficient and control plants. When TYLCV was transmitted via direct injection, JA‐overexpressed and JA‐deficient plants had similar infection levels. The JA‐mediated cessation of vector manipulation thus reduced infection and lessened pathogen impact. 5. The presence of the JA pathway in many plant species suggests that similar interactions may be widespread in nature
    corecore