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Development of next‐generation thermal interface materials (TIMs) with high thermal conductivity is important for thermal management and packaging of electronic devices. The synthesis and thermal conductivity measurements of noncuring thermal paste, i.e., grease, based on mineral oil with a mixture of graphene and few‐layer graphene flakes as the fillers, is reported. The graphene thermal paste exhibits a distinctive thermal percolation threshold with the thermal conductivity revealing a sublinear dependence on the filler loading. This behavior contrasts with the thermal conductivity of curing graphene TIMs, based on epoxy, where superlinear dependence on the filler loading is observed. The performance of the thermal paste is benchmarked against top‐of‐the‐line commercial thermal pastes. The obtained results show that noncuring graphene TIMs outperforms the best commercial pastes in terms of thermal conductivity, at substantially lower filler concentration of φ = 27 vol%. The obtained results shed light on thermal percolation mechanism in noncuring polymeric matrices laden with quasi‐two‐dimensional fillers. Considering recent progress in graphene production via liquid phase exfoliation and oxide reduction, the results open a pathway for large‐scale industrial application of graphene in thermal management of electronics. [ABSTRACT FROM AUTHOR]

The thermal properties of epoxy‐based binary composites comprised of graphene and copper nanoparticles are reported. It is found that the "synergistic" filler effect, revealed as a strong enhancement of the thermal conductivity of composites with the size‐dissimilar fillers, has a well‐defined filler loading threshold. The thermal conductivity of composites with a moderate graphene concentration of fg = 15 wt% exhibits an abrupt increase as the loading of copper nanoparticles approaches fCu ≈ 40 wt%, followed by saturation. The effect is attributed to intercalation of spherical copper nanoparticles between the large graphene flakes, resulting in formation of the highly thermally conductive percolation network. In contrast, in composites with a high graphene concentration, fg = 40 wt%, the thermal conductivity increases linearly with addition of copper nanoparticles. A thermal conductivity of 13.5 ± 1.6 Wm−1K−1 is achieved in composites with binary fillers of fg = 40 wt% and fCu = 35 wt%. It has also been demonstrated that the thermal percolation can occur prior to electrical percolation even in composites with electrically conductive fillers. The obtained results shed light on the interaction between graphene fillers and copper nanoparticles in the composites and demonstrate potential of such hybrid epoxy composites for practical applications in thermal interface materials and adhesives. [ABSTRACT FROM AUTHOR]

Inhibitor of DNA-binding protein 3 (Id3) is required for tumor angiogenesis and regulatory T-cell generation. However, the involvement of Id3 in unexplained repeated implantation failure ( RIF) and recurrent miscarriage ( RM) remains poorly understood. Immunohistochemistry was used to identify Id3, CD34, CTLA-4, and FOXP3 in the endometrium taken from the women with RIF (n=16), RM (n=16) and matched controls (n=8). The images were acquired and analyzed by the Vectra® automated quantitative pathology imaging system. Percentage of Id3+ cells was significantly higher in the endometrium of women with RIF and RM compared with controls. The numbers of Id3+ and CD34+ vessels in the endometrium were positively correlated in control but not in RIF or RM. Percentages of CTLA-4+ cells, but not FOXP3+ cells, were significantly increased in the endometrium of RIF and RM women than those in controls. We found aberrant expressions of endometrial Id3 and CTLA-4 in peri-implantation endometrium of women with RIF and RM, suggesting the negative roles of these angiogenesis and immune tolerance markers involving in regulating endometrium receptivity. [ABSTRACT FROM AUTHOR]

Problem Human chorionic gonadotropin ( hCG) and regulatory T cells (Tregs) have been suggested to play important roles during the initial stage of pregnancy. However, the clinical relevance and mechanism of the effects of hCG on Treg functions in women with recurrent implantation failure ( RIF) remain to be elucidated. Method of study Thirty-four RIF and twenty-three control women were included in the study. Endometrial and peripheral Tregs were analyzed by immunohistochemistry and flow cytometry, respectively. Tregs were generated from naïve CD4+ T cells by stimulation with anti- CD3/ CD28 in the presence or absence of hCG, and the subsets were analyzed by flow cytometry, Western blotting, and qPCR. Results The percentages of endometrial FOXP3+ Tregs and peripheral CCR4+ FOXP3+ Tregs were significantly lower in the women with RIF than in the healthy controls. In addition, the percentages of CCR4+ FOXP3+ Tregs and TGF-β-expressing FOXP3+ Tregs were increased following the stimulation of naïve CD4+ T cells with anti- CD3/ CD28, and these increases were concomitant with AKT and ERK dephosphorylation. Conclusions The results of this study provide novel evidence supporting a role of hCG in regulating the differentiation of peripheral FOXP3+ Tregs. The alterations of circulating Tregs may positively affect the pregnancy outcomes of patients with a history of RIF. [ABSTRACT FROM AUTHOR]

Problem We aimed to investigate the modulatory effects of vitamin D on peripheral blood cellular immune response in patients with recurrent miscarriage ( RM). Method of study The effect of vitamin D on the number of peripheral blood cells, T helper 1 (Th1) cytokines, and NK cytotoxicity was measured in 99 women with RM. Results The percentage of CD19+ B cells and NK cytotoxicity at an effector-to-target cell (E:T) ratio of 50:1, 25:1, and 12.5:1 were significantly higher in the vitamin D insufficiency group ( VDI) than in the vitamin D normal group ( VDN) ( P<.05 each). The proportion of TNF-α-expressing Th cells was significantly higher in the vitamin D deficiency group ( VDD) than in VDN ( P<.05). However, there were no significant differences between VDI and VDD. This dysregulation was significantly reduced with 1,25( OH)2D supplementation. Conclusion The data suggest that the abnormalities of cellular immune response were observed in RM patients with a low vitamin D level, which could be regulated to some extent with 1,25( OH)2D supplementation. [ABSTRACT FROM AUTHOR]

Human coronavirus OC43 (HCoV-OC43) is one of the causes of the 'common cold' in human during seasons of cold weather. The primary function of the HCoV-OC43 nucleocapsid protein (N protein) is to recognize viral genomic RNA, which leads to ribonucleocapsid formation. Here, we characterized the stability and identified the functional regions of the recombinant HCoV-OC43 N protein. Circular dichroism and fluorescence measurements revealed that the HCoV-OC43 N protein is more highly ordered and stabler than the SARS-CoV N protein previously studied. Surface plasmon resonance (SPR) experiments showed that the affinity of HCoV-OC43 N protein for RNA was approximately fivefold higher than that of N protein for DNA. Moreover, we found that the HCoV-OC43 N protein contains three RNA-binding regions in its N-terminal region (residues 1-173) and central-linker region (residues 174-232 and 233-300). The binding affinities of the truncated N proteins and RNA follow the order: residues 1-173-residues 233-300 > residues 174-232. SPR experiments demonstrated that the C-terminal region (residues 301-448) of HCoV-OC43 N protein lacks RNA-binding activity, while crosslinking and gel filtration analyses revealed that the C-terminal region is mainly involved in the oligomerization of the HCoV-OC43 N protein. This study may benefit the understanding of the mechanism of HCoV-OC43 nucleocapsid formation. [ABSTRACT FROM AUTHOR]

The title compound, C(10)H(12)N(2)O(3), crystallizes with two independent mol-ecules in the asymmetric unit which differ in the orientation of the meth-oxy group. Each independent mol-ecule adopts a trans configuration with respect to the C=N bond. In the crystal structure, mol-ecules are linked into chains running along [001] by N-H⋯O and N-H⋯N hydrogen bonds. In addition, an inter-molecular C-H⋯π inter-action is observed.