T Cell Antigen Recognition and Discrimination by Electrochemiluminescence Imaging

Adoptive T lymphocyte (T cell) transfer and tumour-specific peptide vaccines are innovative cancer therapies. An accurate assessment of the specific reactivity of T cell receptors (TCRs) to tumour antigens is required because of the high heterogeneity of tumour cells and the immunosuppressive tumour microenvironment. In this study, we report a label-free electrochemiluminescence (ECL) imaging approach for recognising and discriminating between TCRs and tumour-specific antigens by imaging the immune synapses of T cells. Various T cell stimuli, including agonistic antibodies, auxiliary molecules, and tumour-specific antigens, were modified on the electrode's surface to allow for their interaction with T cells bearing different TCRs. The formation of immune synapses activated by specific stimuli produced a negative (shadow) ECL image, from which T cell antigen recognition and discrimination were evaluated by analysing the spreading area and the recognition intensity of T cells. This approach provides an easy way to assess TCR-antigen specificity and screen both of them for immunotherapies.     

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??This paper studies the price of convertible bonds with counterparty credit risk in a reduced-form model. We suppose that the default intensity process and the interest rate process follow the Vasicek model, and derive the price expression of convertible bonds using the method of measure changes. Moreover, we make some numerical analysis on the explicit formulae to demonstrate the sensitivity of a convertible bond price to changes in the parameters of the model.     

Mesophase separation in polyelectrolyte-mixed micelle coacervates

Mesophase separation has been identified in a polycation/anionic-nonionic mixed micelle system formed by the coacervation of poly(diallyldimethylammoniumchloride)/sodium dodecylsulfate-Triton X-100 in 0.40 M NaCl. The resultant dense, optically clear fluid was studied by turbidity, dynamic light scattering (DLS), and rheology. The presence of two diffusion modes in DLS points to microscopic heterogeneity: coexistence of micelle-rich (dense) domains with micelle-poor (dilute) domains. With an increase in temperature above 20 degrees C, the turbidity rises rapidly along with the intensity of the slow mode. The concomitant decrease in the diffusivity of the slow mode signals an increase in the effective viscosity of the dense domain. With further increase in temperature, dramatic shear thinning is observed, and finally, macroscopic phase separation can be identified by centrifugation. At a temperature near that for quiescent phase separation, we observe shear-induced phase separation. We propose a mechanism to explain the connection between temperature- and shear-induced mesophase separation.     

Eu3+在SrZnP2O7中的发光性能和Eu3+, Bi3+间的能量传递

采用高温固相法合成了SrZnP2O7：Eu^3＋荧光粉,该荧光粉的激发主峰值位于400nm,适用于UVLED管芯的激发;在紫外激发下的发射峰由位于591和597nm（^5D0～^7F1）,616,624和629nm（^5D0～^7F2）,656nm（^5D0～^7F3）及688nm（^5D0～^7F4）4组线状峰构成,对应Eu^3＋的特征跃迁,呈现橙红色发光。分析了Eu^3＋离子浓度对样品发光效率的影响,随着浓度增加,其发射一直增强,但其发光效率已经开始减弱。Bi^3＋的加入使发光强度得到很大提高,并讨论了在SrZnP2O7基质中Bi^3＋对Eu^3＋的能量传递和敏化作用。     

Aggregation properties of cationic gemini surfactants with partially fluorinated spacers in aqueous solution

The aggregation properties of cationic gemini surfactants alkanediyl-alpha,omega-bis(dodecyldimethylammonium bromide), [C(12)H(25)(CH(3))(2)N(CH(2))(m)(CF(2))(n)(CH(2))(m))N(CH(3))(2)C(12)H(25)]Br(2) [where 2m + n = 12 and n = 0, 4, and 6; designated as 12-12-12, 12-12(C(4)(F))-12, and 12-12(C(6)(F))-12, respectively] have been studied by microcalorimetry, time-resolved fluorescence quenching, and electrical conductivity. Compared with a fully hydrocarbon spacer of 12-12-12, the fluorinated spacer with a lower ratio of CF(2) to CH(2) in 12-12(C(4)(F))-12 tends to disfavor the aggregation, leading to larger critical micelle concentration (cmc), lower micelle aggregation number (N), and less negative Gibbs free energy of micellization (DeltaG(mic)). However, the fluorinated spacer with a higher ratio of CF(2) to CH(2) in 12-12(C(6)(F))-12 may prompt the aggregation, resulting in lower cmc, higher N, and more negative DeltaG(mic). It is also noted that enthalpy change of micellization (DeltaH(mic)) for 12-12(C(4)(F))-12 is the most exothermic, but the values of DeltaH(mic) for 12-12-12 and 12-12(C(6)(F))-12 are almost the same. These results are rationalized in terms of competition among the enhanced hydrophobicity and the rigidity of the fluorinated spacer, and the variation of immiscibility of the fluorinated spacer with the hydrocarbon side chains.     

Alzheimer amyloid beta(1-40) peptide: interactions with cationic gemini and single-chain surfactants

The aggregation of amyloid beta-peptide [Abeta(1-40)] into fibril is a key pathological process associated with Alzheimer's disease. The effect of cationic gemini surfactant hexamethylene-1,6-bis-(dodecyldimethylammonium bromide) [C(12)H(25)(CH(3))(2)N(CH(2))(6)N(CH(3))(2)C(12)H(25)]Br(2) (designated as C(12)C(6)C(12)Br(2)) and single-chain cationic surfactant dodecyltrimethylammonium bromide (DTAB) on the Alzheimer amyloid beta-peptide Abeta(1-40) aggregation behavior was studied by microcalorimetry, circular dichroism (CD), and atomic force microscopy (AFM) measurements at pH 7.4. Without addition of surfactant, 0.5 g/L Abeta(1-40) mainly exists in dimeric state. It is found that the addition of the monomers of C(12)C(6)C(12)Br(2) and DTAB may cause the rapid aggregation of Abeta(1-40) and the fibrillar structures are observed by CD spectra and the AFM images. Due to the repulsive interaction among the head groups of surfactants and the formation of a small hydrophobic cluster of surfactant molecules, the fibrillar structure is disrupted again as the surfactant monomer concentration is increased, whereas globular species are observed in the presence of micellar solution. Different from single-chain surfactant, C(12)C(6)C(12)Br(2) has a much stronger interaction with Abeta(1-40) to generate larger endothermic energy at much lower surfactant concentration and has much stronger ability to induce the aggregation of Abeta(1-40).     

The fractional variational iteration method improved with the Adomian series

In this work, an improved version of the fractional variational iteration method is presented, for solving fractional initial value problems. The nonlinear terms of fractional differential equations are linearized via the famous Adomian series. The fractional differential functions are employed in the numerical simulation. Two examples are given as illustrations.     

氨气的制取和性质实验的绿色化研究

用氧化钙与氯化铵反应制取氨气,并将氨气的制备、收集和性质实验组合设计,形成半封闭装置,有效防止了传统方法中试管易炸裂、污染环境和危害人体健康等弊端。该实验方法操作简便、时间短、成功率高,是一种无污染、经济易行的绿色化学实验。     

废旧电池中铜锌锰及氯化铵的分离和利用

为探寻简便有效途径解决废旧电池对环境的污染以及对人体健康危害的问题,在实验中选取常用的锌锰干电池为研究对象,通过酸解、沉淀、氧化还原分别对锌和锰及少量氯化铵进行回收处理,制取七水合硫酸锌和二氧化锰及氯化铵。     

Non-fragile robust output feedback control of uncertain active suspension systems with stochastic network-induced delay

Nonlinear Dynamics - The vehicle active suspension has attracted considerable attention owing to its great contributions to the vertical dynamics of vehicle. This paper investigates the non-fragile...