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Pulsed-laser assisted nanopatterning of metallic layers on silicon substrates under an atomic force microscope (AFM) tip has been investigated. A 532 nm Nd:YAG pulsed laser with a pulse duration of 7 ns was used. Boron doped silicon tips were used in contact mode. This technique enables processing of structures with a lateral resolution down to 10 nm on the copper layers. Nanopatterns such as pit array and multilines with lateral dimensions between 10 and 60 nm and depths between 1.5 and 7.0 nm have been created. The experimental results and mechanism of the nanostructure formation are discussed. The created features were characterized by AFM, scanning electron microscope and Auger electron spectroscopy. The apparent depth of the created pit has been studied as a function of laser intensity or laser pulse numbers. Dependence of nanoprocessing on the geometry parameters of the tip and on the optical and thermal properties of the processed sample has also been investigated. Thermal expansion of the tip, the field enhancement factor underneath the tip, and the sample surface heating were estimated. It is proposed that field-enhancement mechanism is the dominant reason for this nanoprocessing. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated phenylcarbyne polymer films under pulsed green laser irradiation using Raman spectroscopy. Experimental details; Results and discussion; Conclusions.

The superconducting compound [K.sub.3] [C.sub.60] (with transition temperature [T.sub.c] = 19.3 kelvin at ambient pressure), formed as a single phase by reaction of alkali vapor with solids of the icosahedral [...]

OBJECTIVE: Bone loss is the main reason for postmenopausal osteoporosis, caused by estrogen deficiency. ERT (estrogen replacement therapy) has been demonstrated to protect bone loss efficiently. LncRNA (long non-coding RNA) has been proved to be important in different disease progression. We aimed at analyzing whether the lncRNAs influence the activity of osteoclasts and the progression of this disease. PATIENTS AND METHODS: RT-PCR (reverse transcriptase-polymerase chain reaction) was used to detect the expression of lncRNA CRNDE in OH (osteoclast from healthy people) and OP (osteoclast from patients with postmenopausal osteoporosis). MTT (methylthiazolyl tetrazolium) assay was used to detect the viability of the cells. The cell cycle and apoptosis rate in OH and OP were measured by the flow cytometry analysis. Western blot was used to analyze the possible related mechanism that CRNDE regulated the cells proliferation in postmenopausal osteoporosis. RESULTS: We found that the CRNDE was highly expressed in the osteoclast from patients with OP, compared with OH. We also found that overexpressing CRNDE increased the viability in OH whilst reducing CRNDE in OP decreased the viability. The cell cycle was arrested in G0/G1 phase and the apoptosis rate was improved in OP after transfection with siRNA. Moreover, CRNDE could impact the proliferation of osteoclasts by PI3K/Akt signaling pathway and estrogen could inhibit this proliferation. CONCLUSIONS: We found that lncRNA CRNDE was closely related to the postmenopausal osteoporosis with estrogen deficiency. CRNDE may be involved in the development and progression of postmenopausal osteoporosis in the absence of estrogen and become a potential target for treating. [ABSTRACT FROM AUTHOR]

Helping breast cancer patients who desire a pregnancy after cancer treatment is a vital issue. Little is known about the complex context of the decision to become pregnant after breast cancer treatment. The purpose of this study was to understand the risk–benefit perception of choosing conception or contraception after treatment in Taiwan. We applied grounded theory to guide this exploratory qualitative study. Data were collected through in‐depth interviews with 16 breast cancer patients. Pregnancy was addressed in the context of cancer as a potentially life‐threatening diagnosis and its treatment. The verbatim transcriptions were analysed using constant comparative analysis and methods of open, axial and selective coding. The core theme that described the risk perception of pregnancy among patients with breast cancer after treatment focused on “reaching the balance of life.” Seven dimensions of risk–benefit perception of pregnancy, including perceived health status, safety, expected gain, harm, loading, support and time were explored among women treated for breast cancer. We found that women treated for breast cancer applied risk–benefit perceptions to decide whether to become pregnant. Implementing contextual counselling could help to decrease perceived barriers to choose pregnancy and increase the quality of pregnancy care. [ABSTRACT FROM AUTHOR]

This study investigated the epidemiological and clinical characteristics of hepatitis B virus (HBV) in HIV-infected adults at the time of antiretroviral therapy (ART) initiation in Guangdong province, China. A total of 2793 HIV-infected adults were enrolled between January 2004 and September 2011. Demographic data and laboratory parameters were collected, HBV-DNA levels were measured, and HBV genotypes were identified before ART initiation. The prevalence of hepatitis B surface antigen (HBsAg) in HIV-infected patients was 13.2%. A total of 266 HIV/HBV co-infected patients and 1469 HIV mono-infected patients were recruited. The median alanine aminotransferase and aspartate aminotransferase levels of HIV/HBV co-infected patients were higher than HIV mono-infected patients (32 U/L vs. 22 U/L, p < 0.001 and 35 U/L vs. 24 U/L, p < 0.001, respectively), whereas the median CD4 cell count of HIV/HBV co-infected patients was lower than HIV mono-infected patients (59 cells/mm(3) vs. 141 cells/mm(3), p < 0.001). The level of CD4 cell count was lower in hepatitis B e-antigen (HBeAg)-positive co-infected patients than HBeAg-negative patients (36 cells/mm(3) vs. 69 cells/mm(3), p = 0.014). A similar result was found in high level of HBV-DNA and low level of HBV-DNA groups (33 cells/mm(3) vs. 89 cells/mm(3), p < 0.001). HBV genotypes were classified as genotypes B and C. Patients infected with genotypes B and C differed significantly in terms of proportion of those who were HBeAg-positive (40.5% vs. 62.2%, p = 0.014). This study indicates a high prevalence of HBsAg in HIV-infected adults in Guangdong. The level of CD4 cell count in HIV/HBV co-infected patients was much lower than HIV mono-infected patients, especially in patients who were HBeAg-positive and had a high level of HBV-DNA. The predominant HBV genotype in HIV/HBV co-infected patients is genotype B. [ABSTRACT FROM AUTHOR]

Dysregulation of γ-synuclein (SNCG) has been reported in many cancers; however, its role in cancer development is still controversial. Here, we examined the potential involvement of DNA methylation in regulating SNCG and its role in oral squamous cell carcinoma (OSCC). We used 8 OSCC cell lines to investigate SNCG methylation and expression. SNCG methylation was examination by methylation-specific polymerase chain reaction and bisulfate sequencing. Cells showing a high degree of SNCG methylation were treated with 5-aza (methylation inhibitor), and changes in their methylation and expression profiles were analyzed. Functional effects of SNCG in OSCC were examined by its overexpression and knockdown. Additionally, methylation and expression of SNCG in OSCC tissues were investigated and correlated with clinicopathologic features. All OSCC cells showed detectable SNCG expression at the mRNA and protein levels. Methylation-specific polymerase chain reaction and bisulfate sequencing revealed high SNCG expression in SCC25 cells with the unmethylated allele, and their 15 CpG islands were unmethylated. The methylated allele was detected only in OEC-M1 cells exhibiting low SNCG expression, and their CpG islands were partially methylated. 5-aza treatment in OEC-M1 cells attenuated methylation and restored SNCG expression. SNCG overexpression increased colony forming, migration, and invasion abilities in OEC-M1 cells. Silencing SNCG in SCC25 cells suppressed these behaviors. All 25 tumor-adjacent normal tissues were negative for SNCG immunostaining. SNCG upregulation was frequently observed in dysplastic and OSCC tissues. Positive SNCG expression was found in 45% (37 of 82) OSCC tissues. Positive SNCG expression in OSCC significantly correlated with cancer staging and lymph node metastasis. However, SNCG methylation did not correlate with its expression and clinicopathologic variables in OSCC tissues. DNA methylation may participate in regulating SNCG expression in some OSCC cells. SNCG upregulation could be involved in OSCC progression. [ABSTRACT FROM AUTHOR]