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Previous studies have proved that fibrin is an excellent scaffold material for tissue engineered blood vessel. However, the mechanical properties of fibrin are not enough. One way to solve the problem is to combine polymer materials with fibrin to enhance its biomechanical properties. In this study, a novel polycaprolactone (PCL)/fibrin composite scaffold was prepared by electrospinning technology. The morphological, physicochemical analysis, blood compatibility, biomechanical properties, biocompatibility and biodegradability of this vascular scaffold were evaluated. The results showed that electrospun PCL/fibrin scaffold possessed smaller aperture and larger fiber diameter than that of fibrin scaffold. The swelling ratio of the vascular PCL/fibrin scaffold at (0:100), (10:90), (20:80) and (30:70) was 112 ± 5.3, 103 ± 6.9, 94 ± 5.9 and 89 ± 3.4%, respectively. Mechanical properties of fibrin scaffolds were enhanced significantly by the addition of PCL. Furthermore, the time of plasma re-calcification, activated partial thromboplastin time and thromboplastin time in four different proportions of PCL/fibrin scaffolds were similar to that of the control group. Degradation experiments

Novel Janus nanoparticles (J-NPs) are developed by using single iron oxide (Fe3O4) nanoparticles as the core and hydrophobic/hydrophilic polymeric brushes as the cloak. Because of the superparamagnetism and asymmetric functionality of J-NPs, they are used as drug carriers and therapeutic agents for cancer chemotherapy and magnetic hyperthermia with a magnetic resonance imaging (MRI) guide. The asymmetric functionality is constituted of hydrophobic polymethyl methacrylate (PMMA) brushes and hydrophilic polyacrylic acid (PAA) brushes, which are 'grafting to' or 'grafting from' Fe3O4 nanoparticles via activators regenerated by electron transfer atom transfer radical polymerization. The terminal chains of PMMA and PAA brushes are coordinated with Fe3O4 nanoparticles, so PMMA/Fe3O4/PAA J-NPs possess structural stability in solvents. Because of the brush-structure, PMMA/Fe3O4/PAA J-NPs show high encapsulation efficiency (89.75 ± 2.35%) and loading capacity (8.95 ± 0.26%). Under the alternating magnetic field (AMF), drug-loaded J-NPs achieve the highest cell proliferation-inhibition ratio in the cell proliferation test in vitro and the tumor growth inhibition test in vivo compared to single chemotherapy or magnetic hyperthermia. Meanwhile, J-NPs show good T2 imaging.

In this report, a novel type of carbon dots (CDs) were prepared via a simple MW-assisted method by using citric acid and piperazine as precursors. The CDs can be obtained in large-scale and emit bright solid-state fluorescence (SSF) with different colors. Then the synthetic CDs were fully characterized with PL, UV, XPS, TEM, and FTIR and the relationship between the mass ratio of precursors and physicochemical property of the CDs was also investigated detailedly. The results showed that these CDs prepared at different mass ratios have different element content and functional group content. More importantly, the mass ratio of the precursors not only has a great influence on their particle sizes, but also can affect their PL properties. With the decreased of the mass ratio, their particle size decreased gradually and their emission wavelength gradually red-shift. This interesting finding may be helpful for fabricating CDs with controllable particle size and tunable light-emitting colors. Based on their excellent SSF property, these CDs were successfully used to fabricate light-emitting diodes (LEDs) and detect latent fingerprints (LFPs). In conclusion, the research may offer a valuable reference for obtaining CDs with SSF and developing LEDs phosphors and LFPs detection reagent.

Repopulation of decellularized vascular scaffolds (DVS) is limited because of change in the repertoire and ratios of the remaining extracellular matrix (ECM) proteins, for example, loss of glycoproteins and the retention of type I collagen. Pre-treatment of DVS with defined ECM proteins, which match the repertoire of integrin receptors expressed by the embryonic stem cells (mESCs) to be seeded, can increase the reseeding efficacy. mESCs mainly express high levels of functional receptors for LM and FN. Reseeding efficiency of DVS with mESCs was very low, but was sigficantly increased (2.5 ± 0.1 fold) by pre-treating the DVS with A549-conditioned media. In addition, pre-treatment with A549-conditioned media led to a more homogeneous distribution of the seeded mESCs throughout the engineered blood vessel as compared to untreated DVS. This paper may promote blood vessel engineering by stressing the importance of matching the cell binding motifs of DVS and the integrin receptor repertoire of seeded cells.

By optical microscopy and SEM-energy spectrometry, some phenomena that relate to lake-bottom hydrothermal activities, such as the presence of siliceous rocks, ankerite laminar deposits, evidence for marcasite brassil anhydrite symbiosis systems and authigenetic albite filling in early diagenetic fractures, have been discovered in the Chang 7 high-quality source beds of the Yanchang Formation, Ordos Basin. Various geochemical data of the Chang 7 high-quality source rocks testify further to the existence of lake-bottom hydrothermal activities, and they include abnormally abundant S2- content (on average 7.37%), Mo, Cu, U and Mn positive anomalies, high ratios of U to Th, the positive carbon isotope composition of crystalline ankerite (δ13C from 2.88 to 3.03‰), depleted oxygen isotope composition (δ18O PDB from −16.41 to −16.17‰), the enrichment of microelements like Cu and Mn, and isotopically enriched in 34S sulfur isotope compositions of strawberry-shaped pyrite (δ34S CDT from 2.37 to 5.90‰). In the early sedimentary period of the Chang 7, the activation of floor ruptures by violent regional structural activities was a dynamic factor that produced lake-bottom hydrothermal activities. The hydrothermal activities played an important role in accelerating the extensive development of the Chang 7 high-quality source rocks. 摘 要: 光学显微镜和扫描电子显微镜-能谱仪观测在鄂尔多斯盆地延长组长7优质烃源层中发现了硅质岩、铁白云石纹层沉积、白铁矿-黄铁矿-硬石膏共生体系、早期成岩缝中的自生钠长石充填作用等可能与湖底热水活动有关的现象。能进一步佐证同期湖底热水活动存在的证据还有：长7优质烃源岩中异常高的二价硫含量（平均7.37%），Mo、Cu、U、Mn等微量元素的显著正异常特征，高的U/Th值，微晶铁白云石纹层偏重的碳同位素组成（2.88‰～3.03‰)、偏轻的氧同位素组成（－16.41‰～－16.17‰）和富集Cu、Mn等微量元素的特征，莓状黄铁矿偏正的硫同位素组成（2.37‰～5.90‰）特征等。长7段沉积期始，强烈的区域构造活动对基底断裂的激活作用是产生湖底热水活动的动力学因素，湖底热水活动对长7优质烃源岩的大规模发育具有重要的促进作用。图6表1参14 Key words: lake-basin expansion, lake-bottom hydrothermal activity, high-quality source rock, Late Triassic, Ordos Basin