Optimization of the Thermally Conductive Low-k Polymer Dielectrics Based on Multisource Free-Volume Effects.

Polymers/polymer matrix composites possessing low dielectric constants (low-k polymer dielectrics) contribute to the advance of electronics, for instance, microprocessor chips, mobile phone antennas, and data communication terminals. However, the intrinsic long-chain structural characteristic results in poor thermal conductivities, which draw heat accumulation and undermine the outstanding low-k performance of polymers. Herein, multisource free-volume effects that combine two novel kinds of extra free volume with the known in-cage free volume of polyhedral oligomeric silsesquioxanes (POSSs) are discussed to reduce the capacity for dielectric constant reduction. The multisource free-volume effects of POSSs are associated with the thermal conductive network formed by the hexagonal boron nitride (BN) in the polymer matrix. The results show a decent balance between low-k performance (dielectric constant is 2.08 at 1 MHz and 1.98 at 10 GHz) and thermal conductivity (0.555 W m-1 K-1, 4.91 times the matrix). The results provide a new idea to maximize the free-volume effects of POSSs to optimize dielectric properties together with other desired performances for the dielectrics.

A Gas Therapy Strategy for Intestinal Flora Regulation and Colitis Treatment by Nanogel-Based Multistage NO Delivery Microcapsules.

Current approaches to treating inflammatory bowel disease focus on the suppression of overactive immune responses, the removal of reactive intestinal oxygen species, and regulation of the intestinal flora. However, owing to the complex structure of the gastrointestinal tract and the influence of mucus, current small-molecule and biologic-based drugs for treating colitis cannot effectively act at the site of colon inflammation, and as a result, they tend to exhibit low efficacies and toxic side effects. In this study, nanogel-based multistage NO delivery microcapsules are developed to achieve NO release at the inflammation site by targeting the inflammatory tissues using the nanogel. Surprisingly, oral administration of the microcapsules suppresses the growth of pathogenic bacteria and increases the abundance of probiotic bacteria. Metabolomics further show that an increased abundance of intestinal probiotics promotes the production of metabolites, including short-chain fatty acids and indole derivatives, which modulate the intestinal immunity and restore the intestinal barrier via the interleukin-17 and PI3K-Akt signaling pathways. This work reveals that the developed gas therapy strategy based on multistage NO delivery microcapsules modulates the intestinal microbial balance, thereby reducing inflammation and promoting intestinal barrier repair, ultimately providing a new therapeutic approach for the clinical management of colitis.

Research Progress in Extraction, Separation, Purification and Biological Activities of Sanshoolin Zamthoxyli Pericarpium / 中国中医药信息杂志

As medicine and food plants, the market demand of Zamthoxyli Pericarpium is extensive, and the sanshool in Zamthoxyli Pericarpium is getting attention gradually. However, because of the low content and not establishing rating evaluation method for sanshool and lack of standards, the research on substance basis and physiological activity is necessary. This article reviewed the extraction, separation, purification and biological activities of sanshoolin Zamthoxyli Pericarpium in recent years to provide development and utilization of Zamthoxyli Pericarpium.

Molecular background of weak D type 15 as the predominant weak D type found in Chinese population / 中国实验血液学杂志

This study was aimed to investigate the molecular genetic basis and serological phenotype of Rh weak D type 15 individuals. Samples were identified by serological tests and genotyped by sequence specific primer-PCR (SSP-PCR), and were sequenced to detect the changes of all ten RHD exons. The number of gene RHD was detected through SSP-PCR. The results showed that in tested individuals of weak D type confirmed by the IAT, 18 cases (56% in weak D) were weak D type 15. Rh factors found in 2 weak D type 15 individuals (11%) were C+c+E+e; Rh factors found in 2 weak D type 15 individuals (11%) were C+c+E-e+; others (78%) were c-c+E+e+. The results by serological tests were consistent with the results genotyped by PCR-SSP method. In all 18 samples, the sequencing result revealed a gene mutation 845G > A at the exon 6 of the RHD and the point mutation changed amino acid G282D of the RhD polypeptide. The zygosity test demonstrated that 2 out of 18 weak D type 15 individuals were RHD(+)/RHD(+) homozygous (two DCe/DcE), 16 cases were RHD(+)/RHD(-) heterozygous (two DCe/dce and fourteen DcE/dce). It is concluded that Weak D type 15 is predominant in weak D individuals of Chinese Han Nationality, and most of them are heterozygous with various RH haplotypes.

Analysis of genetic polymorphism in randomized donor's HPA 1-16 antigens and establishment of typed platelet donor data bank / 中国实验血液学杂志

To study the genetic polymorphism of HPA 1-16 platelet antigen alleles among unrelated volunteer donors and establish a typed platelet donor panel in Handan, typing was perfomed by polymerase chain reaction using sequence-specific primers (SSP-PCR); 148 random unrelated blood donors in Handan were genotyped for each of the HPA 1-16 antigen. The gene frequencies were analyzed and the genetype frequencies were determined by direct counting, and these data were compared with HPA distribution among various population by the chi-square test. The results indicated that HPA-1a, 2a, 4a-14a, 16a genes were found among the 16 HPAs in every sample tested. Monomorphic HPA-4a, 7a-14a, 16a were found in the samples. For HPA-1, 2, 5 and 6, a/a homozygosity was predominant with frequencies of 0.9595, 0.8108, 0.9865, 0.9797, respectively, and none of HPA b/b was found in the samples. HPA-1b, 2b, 5b, 6b were rarely found among subjects. HPA-15 had the greatest heterozygosity with a gene frequency of 0.2230, 0.5270, 0.2500 for HPA15a/15a, HPA15a/15b, HPA15b/15b, respectively. HPA-3 showed the second greatest heterozygosity with a gene frequency of 0.3851, 0.5135, 0.1014 for HPA3a/3a, HPA3a/3b, HPA3b/3b, respectively. HPA genotype frequencies showed a good fit to Hardy-Weinberg equilibrium. HPA1-5 gene frequencies for Chinese people in Handan were consistent with those of Chinese people in Shijiazhuang (P > 0.05). Among the HPA1-13, -15, the frequencies of HPA-1, -2, -6 for Chinese people in Handan differed appreciably from those for Chinese people in Taiwan (P < 0.05), others were similar to those of Chinese people in Taiwan. Among the HPA 1 - 8, a similarity was noted between Chinese people in Handan and Koreans (P > 0.05), except for HPA-3. Frequencies of HPA-1, -2, -5 significantly were differed from those in African Americans, as compared with HPA 1-5 (P < 0.05). Comparison of gene frequencies from HPA-1 and -5 showed significant differences between Chinese people in Handan and people in UK (P < 0.05). It is concluded that HPA-2, -3, -5, -15 of people in Western region of China have polymorphism, incompatible frequency of HPA antigen distribution is higher, which inevitably results in the increase of immunologic exposure, therefore attention must be paid to the importance of HPA-2, -3, -5, -15 in clinical disorders. This study for the first time completely analyses HPA1-16 gene frequencies in China, and provides data for establishing a typed platelet donor panel in Handan, China.