Herein, we prepare vertical and single crystalline porous silicon nanowires (SiNWs) via a two-step metal-assisted electroless etching method. The porosity of the nanowires is restricted by etchant concentration, etching time and doping lever of the silicon wafer. The diffusion of silver ions could lead to the nucleation of silver nanoparticles on the nanowires and open new etching ways. Like porous silicon (PS), these porous nanowires also show excellent photoluminescence (PL) properties. The PL intensity increases with porosity, with an enhancement of about 100 times observed in our condition experiments. A “red-shift” of the PL peak is also found. Further studies prove that the PL spectrum should be decomposed into two elementary PL bands. The peak at 850 nm is the emission of the localized excitation in the nanoporous structure, while the 750-nm peak should be attributed to the surface-oxidized nanostructure. It could be confirmed from the Fourier transform infrared spectroscopy analyses. These porous SiNW arrays may be useful as the nanoscale optoelectronic devices.

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Background PTPN11, which encodes tyrosine phosphatase Shp2, is a critical gene mediating cellular responses to hormones and cytokines. Loss of Shp2 promotes hepatocellular carcinoma (HCC), suggesting that PTPN11 functions as a tumor suppressor in HCC tumorgenesis. The aim of this study was to evaluate the effects of the short tandem repeat (STR) polymorphism (rs199618935) within 3'UTR of PTPN11 on HCC susceptibility in Chinese populations.Methodology/Principal FindingsWe analyzed the associations in 400 patients from Jiangsu province of China, validating the findings in an additional 305 patients from Shanghai of China. Unconditional logistic regression was used to analyze the association between rs199618935 and HCC risk. Additional biochemical investigations and in-silico studies were used to evaluate the possible functional significance of this polymorphism. Logistic regression analysis showed that compared with individuals carrying shorter alleles (11 and 12 repeats), those subjects who carry longer alleles (13 and 14 repeats) had a significantly decreased risk of HCC [adjusted odds ratio (OR)  = 0.63, 95% confidence interval (CI)  = 0.53–0.76, P = 2.00×10−7], with the risk decreased even further in those carrying allele 15 and 16 (adjusted OR = 0.46, 95% CI = 0.34–0.62, P = 1.00×10−7). Biochemical investigations showed that longer alleles of rs199618935 conferred higher PTPN11 expression in vivo and in vitro. The altered luciferase activities in reporter gene system suggested that STR regulation of PTPN11 expression could be a transcriptional event. Finally, in-silico prediction revealed that different alleles of rs199618935 could alter the local structure of PTPN11 mRNA.Conclusions/SignificanceTaken together, our findings suggested that the STR polymorphism within PTPN11 contributes to hepatocarcinogenesis, possibly by affecting PTPN11 expression through a structure-dependent mechanism. The replication of our studies and further functional studies are needed to validate our findings.

Ischemic stroke is one of the major causes of death and long-term disability worldwide. C-reactive protein (CRP) as a potential biomarker for functional outcome after acute ischemic stroke remains controversial. The aim of the present study was to examine the association between the level of CRP and functional outcome of stroke. A total of 218 consecutive patients with acute ischemic stroke within 24 h after onset were recruited for the study. Poor functional outcome was defined as a modified Rankin scale score of >2 at 3 months after stroke. The retrospective analysis was performed to investigate whether CRP within 24 h after stroke is associated with poor functional outcome at 3 months. Multivariate logistic regression analysis indicated that the CRP level (odds ratio=1.146, 95%CI: 1.012-1.297, P=0.031) was an independent risk factor for poor outcome. The receiver operating characteristics curve analysis revealed that the optimal cut-off value of CRP to distinguish favorable from poor outcome was 6.34 (area under the curve=0.829, 95%CI: 0.772-0.887, P<0.001), with 68.2% sensitivity and 85.7% specificity. Spearman correlation analysis indicated that the CRP level was positively related to the baseline National Institutes of Health Stroke Scale (NIHSS) score (r=0.551, P<0.001), fasting glucose (r=0.301, P<0.001) and age (r=0.252, P<0.001). In conclusion, a high level of CRP within 24 h after onset was associated with a poor functional outcome after the acute ischemic event. The elevation of CRP may be correlated with the baseline NIHSS score, fasting glucose and age.

In this study, 349 Han and 217 Tibetan college students were investigated via the Templer Death Anxiety Scale in order to assess the potential class and influencing factors of death anxiety among them. In addition, Mplus software was used to analyse the latent categories of their death anxiety, and an R3STEP approach was adopted to perform a multinomial logistic regression of its influencing factors. Whilst the results of the former indicated that there are two latent classes, respectively, defined as ‘high death anxiety type’ (Han 65.20%; Tibetan 30.30%) and ‘low death anxiety type’ (Han 34.80%; Tibetan 69.70%), the latter demonstrated that compared with the ‘low death anxiety type’, the occurrence ratio of the ‘high death anxiety type’ was 47.00 and 34.04 percentage points higher with each increase in age. Furthermore, the stress and anxiety of Han and Tibetan college students were found to constitute factors that affect death anxiety. More specifically, the death anxiety of Tibetan college students was determined to be deeply influenced by a belief in the afterlife.