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Objectives Smoking prevalence has significantly increased among Chinese adolescences in the past decades. The aim of our study is to investigate the trends and changing patterns in age of smoking initiation among the Chinese population. Study design Pooled data from the 2006–2015 China Health and Nutrition Survey was used for analysis. A total of 10,032 adults aged ≥18 years who were born between 1950 and 1997 were separated into five birth cohorts (1950–1959, 1960–1969, 1970–1979, 1980–1989 and 1990–1997). Methods Age-specific (10–24 years) smoking initiation rates were calculated by gender, educational level and urbanisation. The multiple logistic models were used for estimates of changes in smoking initiation age. Results The mean age of smoking initiation decreased substantially from 22.0 years (95% confidence interval [CI]: 21.2–22.7) to 17.5 years (95% CI: 16.2–19.1) over five generations. A large decrease was seen in the initiation age group of 15–24 years in the 1980s cohort (15–19 years: odds ratio [OR] = 0.57; 95% CI: 0.19–0.97; 20–24 years: OR = 0.45; 95% CI: 0.18–0.82); a significant decrease was also found in the 1990s cohort (15–19 years: OR = 0.47; 95% CI: 0.11–0.94; 20–24 years old: OR = 0.34; 95% CI: 0.14–0.85). The peak age of smoking initiation changed from 20 years old to 18 years old over the five generations. Conclusions The age of smoking initiation has decreased rapidly in the Chinese population in the past decades. Chinese adolescents are becoming the main target group for the tobacco marketing industry, and national legislations are urgently required.

Temperature-dependent photoluminescence spectra of the germanium bottom cell of triple-junction solar cells unirradiated and irradiated with 1 MeV electrons were measured in the 10–300 K te...

We demonstrate the concept of fiber-based terahertz hook. The subwavelength photonic hook is obtained in the vicinity of a shaped fiber tip with asymmetric radiation. A 193 THz continuous-wave source, commonly used for medical imaging, has been required. Photonic hook with a lateral feature size less than the half-wavelength is achieved using a hemispherical shaped fiber tip with metallic mask. This breakthrough is carried out in ambient air by using a 2.58λ - diameter fiber with a shaped tip (λ is a radiation wavelength). A good correlation is observed between the computed intensity distribution of photonic hook and the tip sizes. Photonic hook generated with a shaped fiber tip, easier to manipulate, shows far-reaching benefits for potential applications such as ophthalmic laser surgery, super-resolution microscopy, photolithography, and material processing.

Structured light have made deep impacts on modern biotechnology and clinical practice, with numerous optical systems and lasers currently being used in medicine to treat disease. We demonstrate a new concept of fiber-based optical hook scalpel. The subwavelength photonic hook is obtained in the vicinity of a shaped fiber tip with asymmetric radiation. A 1550 nm continuous-wave source, commonly used for medical imaging, has been required. Photonic hook with a lateral feature size less than the half-wavelength is achieved using a hemispherical shaped fiber tip with metallic mask. This breakthrough is carried out in ambient air by using a 4-μm-diameter fiber with a shaped tip. A good correlation is observed between the computed intensity distribution of photonic hook and the tip sizes. Photonic hook generated with a shaped fiber tip, easier to manipulate, shows far-reaching benefits for potential applications such as ophthalmic laser surgery, super-resolution microscopy, photolithography and material processing.

The open-circuit voltage (VOC) degradation for individual subcell in 1.0 MeV electrons-irradiated GaInP/GaAs/Ge solar cells has been analyzed using electroluminescence (EL) measurements. By using the relationship between VOC degradation and electron fluence, the capture cross section of the defects induced by electron irradiation in individual subcells were determined. Furthermore, by comparing the thermal activation energy and capture cross section, a defect located at Ev+0.55 ​eV styled H2 hole trap is nonradiative recombination centre in GaInP subcell, a defect located at EC-0.96 eV styled E5 electron trap is nonradiative recombination centre in GaAs subcell, and a defect located at EC-0.38 eV styled E-center electron trap is nonradiative recombination centre in Ge subcell.

For small area estimation (SAE) Spatial Empirical Best Linear Unbiased Prediction, SEBLUP, is involved in linear mixed model with spatial correlation while Empirical Best Linear Unbiased Prediction, EBLUP, often with mutual independence. In this paper, we discussed maximum likelihood estimation (MLE) and compared the efficiency. Simulation shows that SEBLUP with spatial correlation data of spatial small area is more effective than EBLUP.

The mechanism of Rh n + (n = 1 − 3) catalyzed methane activation has been investigated theoretically. All structures on the potential energy surfaces are optimized at the density functional theory (DFT) level, using the empirically parametrized hybrid functional B3LYP. Relative energies are calculated both at the B3LYP level, using large basis sets RECP+6-311+G**. The B3LYP energies of important species on the potential energy surfaces were compared to CCSD(T) single-point energy calculations. All the three systems are two-state reactivity. For Rh+ and Rh 2 + with methane, the product are metal–carbene and hydrogen and the two reaction endothermic by 28.05 kcal/mol and 1.84 kcal/mol, respectively. While for Rh 3 + with methane, the product is a hydrogen-bridge bond molecule and the reaction exothermic by 55.30 kcal/mol so it can be performed spontaneously at room temperature. With the increase of the metal atom numbers n, the catalytic activity of Rh n + towards methane C–H bonds rise sharply, then the Rh 3 + is likely to be a better mediator than Rh+ and Rh 2 + for the activation of methane.

Dual-level direct dynamics method is employed to study the kinetics of the multiple-channel reaction CH 3 OBr + Cl − for the first time. Geometries have been optimized at the MP2 level with the 6-311+G(d,p) basis set. The minimum energy path is calculated at the same level and further refined at the QCISD(T)/6-311++G(3df,2p) level. The rate constants are obtained by using the canonical variational transition state theory incorporating small-curvature tunneling correction in the temperature range of 200–3000 K. The results show that anti -E2 elimination reaction channel is the dominant channel over the whole temperature range and the corresponding rate constants present negative temperature dependence in the low temperature range, while positive temperature dependence in the high temperature range. The three-parameter Arrhenius expression k = 2.61 × 10 −18 T 2.29 exp(1395.19/T) for the overall reaction is also given.

The residential regions of Yunnan province, canton of Jing Hong, in China were surveyed for Japanese encephalitis virus (JEV) infection in mosquito and swine vectors to determine the frequency of JEV-carrying zoonotic vectors in 2009-2010. A total of 21,500 mosquitoes were collected and divided by species, and brain tissue was collected from 108 stillborn piglets. The infection rates for the different JEV species were 13.2% for Culex tritaeniorhynchus, 2.7% for Anopheles sinensis, 0.7% for Armigeres subalbatus, and 18.5% for stillborn piglets. The complete genomes of two JEV samples that were collected in different seasons and different regions, Yunnan 0901 and Yunnan 0902, were sequenced from a pool of Culex mosquitoes and stillborn piglets that had been collected randomly from several piggeries. Multiple sequence alignment with 24 fully-sequenced genes and 93 complete sequences of the JEV-encoded E gene revealed nucleotide homologies ranging from 97.2-99.6% and 94.5-99.7% in mosquitoes and piglets, respectively, and deduced amino acid homologies ranging from 97.4-98.1% and 96.0-98.2%, respectively. Phylogenetic analyses of the Yunnan 0901 and Yunnan 0902 strains' full-length genomes and E gene sequences indicated that these strains are most closely related to six Chinese SA14-derived viruses, and distantly related to the Australian FU, vellore P20778, and Japanese Ishikawa strains, and the previously isolated YN86-B8639 strains. The phylogenetic relationships based on the full-length genome were similar to those found for the E gene, indicating that phylogenetic analysis of the E gene will be a useful approach for genotyping of JEV, but not to better understand the potential changes in the biological characteristics and genetic relationship of JEV isolates.

Japanese encephalitis (JE) can infect many agriculturally important animals and humans, and has a high incidence in Asia. One of the natural hosts of the mosquito-borne JE virus (JEV) is domestic pigs, which act as amplifier hosts. Porcine infection results in fatal encephalitis, abortion, and stillbirth in pregnant sows, and hypospermia in boars. In this study, a rapid JEV detection method for swine and mosquitoes was developed based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) targeting the nucleocapsid (E) genes of JEV genotype I (lineage K94PO5), and genotype III (lineage SA14-14-2). Fifty-six swine blood samples and 20,000 mosquitoes were used to evaluate the method, compared to conventional RT-polymerase chain reaction (PCR) and real-time RT-PCR. RT-LAMP had detection limits of 2.57 and 2.34 copies/μL for JEV I and III, respectively. Assay sensitivity was similar to real-time RT-PCR, but was 10-fold higher than conventional RT-PCR. Assay specificity was high, showing no cross-reactivity to other flaviviruses. The results of virus isolation and identification of swine blood samples and mosquito samples were fully consistent with RT-LAMP. Finally, the JEV RT-LAMP assay was simpler and less time consuming than conventional RT-PCR or real-time RT-PCR, since the amplification step could be completed in a single tube within 50 min at 63°C. In conclusion, the newly-developed RT-LAMP assay is an accurate and convenient method for rapid and sensitive diagnosis of JEV in swine and mosquitoes, and may prove to be a practical molecular tool for surveillance and epidemiological investigations.

R-spondin 1 (Rspo1) plays an essential role in stem cell biology by potentiating Wnt signaling activity. Despite the fact that Rspo1 holds therapeutic potential for a number of diseases, its biogenesis is not fully elucidated. All Rspo proteins feature two amino-terminal furin-like repeats, which are responsible for Wnt signal potentiation, and a thrombospondin type 1 (TSR1) domain that can provide affinity towards heparan sulfate proteoglycans. Using chemical inhibitors, deglycosylase and site-directed mutagenesis, we found that human Rspo1 and Rspo3 are both N-glycosylated at N137, a site near the C-terminus of the furin repeat 2 domain, and Rspo2 is N-glycosylated at N160, a position near the N-terminus of TSR1 domain. Elimination of N-glycosylation at these sites affects their accumulation in media but have no effect on the ability towards heparin. Introduction of the N-glycosylation site to Rspo2 mutant at the position homologous to N137 in Rspo1 restored full glycosylation and rescued the accumulation defect of nonglycosylated Rspo2 mutant in media. Similar effect can be observed in the N137 Rspo1 or Rspo3 mutant engineered with Rspo2 N-glycosylation site. The results highlight the importance of N-glycosylation at these two positions in efficient folding and secretion of Rspo family. Finally, we further showed that human Rspo1 is subjected to endoplasmic reticulum (ER) quality control in N-glycan-dependent manner. While N-glycan of Rspo1 plays a role in its intracellular stability, it had little effect on secreted Rspo1. Our findings provide evidence for the critical role of N-glycosylation in the biogenesis of Rspo1.

To investigate characteristics of circadian rhythm in intracerebral hemorrhage before death.This retrospective study was carried out from September 2002 to February 2009. One hundred and twenty-two dead cases with intracerebral hemorrhage(ICH) were collected. The study was carried out in the Department of Neurosurgery in The Second Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China. Blood pressure (BP) and heart rate (HR) were recorded every half-hour during the 72 hours before death. Data of BP and HR before deaths were divided into 3 time periods, namely, period A (72-48 hours to death), period B (48-24 hours to death), and period C (24 hours to death). Data from the 3 periods were analyzed using the Cosinor method to determine whether circadian rhythm was present or absent. The cases were divided into a present and absent group after Cosinor analysis. Prognostic factors in the 2 groups were analyzed by Student`s t-test and Pearson`s chi-squared test.Significant differences in prognostic factors between the 2 groups were not found. When circadian midline-estimating statistic of rhythms over the 3 periods were compared, there were no significant differences. However, when circadian amplitudes over the 3 periods were compared, the amplitudes during period C were significantly lower than period A or B (p0.001). The percentage of cases in the absent and present groups was significantly different (p0.001) over the 3 periods.As an independent factor, circadian variation could predict death in patients with ICH.

Prophylactic DNA vaccines against the influenza virus are promising alternatives to conventional vaccines. In this study, we generated two candidate gene-based influenza vaccines encoding either the seasonal or pandemic hemagglutinin antigen (HA) from the strains A/New Caledonia/20/99 (H1N1) (pV1A5) and A/California/04/2009 (H1N1) (pVEH1), respectively. After verifying antigen expression, the immunogenicity of the vaccines delivered intramuscularly with electroporation was tested in a mouse model. Sera of immunized animals were tested in hemagglutination inhibition assays and by ELISA for the presence of HA-specific antibodies. HA-specific T-cells were also measured in IFN-γ ELISpot assays. The protective efficacy of the candidate influenza vaccines was evaluated by measuring mortality rates and body weight after a challenge with 100 LD50 of mouse-adapted A/New Caledonia/20/99 (H1N1). Mice immunized with either one of the two vaccines showed significantly higher T cell and humoral immune responses (P

To study the influence of different surgery on heart rate's circadian rhythm in postoperation of intracerebral hemorrhage.One hundren cases of hypertensive intracerebral hemorrhage at basal ganglia had been collected. According to methods of operation, cases were divided into two groups. Forty-three cases and 57 cases were treated respectively by standard craniotomy (Craniotomy group) and microinvasion of puncturation (Microinvasion group) to remove hematoma. Value of heart rate (HR) was recorded by monitor every 1 hour for 9 days. Circadian rhythm of every day was analyzed by single cosinor and population mean-cosinor.Circadian rhythm of postoperative HR appeared (P0.001) in microinvasion group after operation. Circadian rhythm of postoperative HR had not been appearing (P0.001) in craniotomy group until to the 8th day. All amplitudes in microinvasion group are higher than that in craniotomy group. Both of amplitudes in two groups begin to be low during 4-7 d after operation and recover the level till the 8th day.Influence of circadian rhythm in craniotomy was more severe than microinvasion puncturation. There would be a intimate relationship between encephaledema and recovery of circadian rhythm after neurosurgery.