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Hepatocarcinogenesis, a multistep process, involves not only genetic mutations but also epigenetic alterations. Widespread of global DNA hypomethylation is accompanied with specific regional hypermethylation especially at tumor suppressor genes' promoters. The aim of this study is to determine the efficacy of combined DNA methylation analysis of a global DNA methylation marker - LINE-1 and a tumor suppressor gene highly associated with the malignancy of HCC- RASSF1A in serum as a novel prognostic marker for diagnosis of early recurrence after curative resection.LINE-1 was hypomethylated in 66.7% (70/105) and RASSF1A promoter was hypermethylated in 73.3% (77/105) of HCC serum DNA samples by methylation specific PCR, but in none of the healthy controls: LINE-1 hypometylation (0/50) and RASSF1A hypermethylation (0/50). A significant association was found between LINE-1 hypomethylation and clinical pathologic features including HBsAg positivity (p=0.009), tumor size (p=0.001) and AFP levels (p

Fast detection and identification of chemicals are of utmost importance for field testing and real-time monitoring in many fields. Raman spectroscopy is the predominant technique in principle, but its wide application is limited on account of weak scattering efficiency. Surface Enhanced Raman Spectroscopy (SERS) technique provides a solution for signal enhancement, but may not good at fast detection due to cross contamination and bulky instruments. Hollow-core fiber-based Raman cell with long interaction length can achieve high detection sensitivity, but it also suffers from low flow rate, bulky high-pressure equipment and light coupling structure, which also restricts its application for fast detection. In order to solve those problems, we proposed a portable Raman cell, by using metal-lined hollow-core fibers (MLHCF) with large bandwidth, good field confinement, extremely large numerical aperture and arbitrary length. With our proposed fiber inserted light coupling and light reflecting method, a Raman cell of 3.1 cm in length provides nearly 50 times of signal enhancement compared with direct detection using bare fiber tip. Furthermore, the sample exchange rate could be as fast as 1 second even under normal pressure without any cross contamination. At last, we also demonstrated the underlying general mechanism of signal enhancement and summarized it as volumetric enhancement of Raman scattering (VERS). Both the experiment results and the theoretical analysis demonstrated that our device has the potential for fast online Raman detection, which also possesses high-sensitivity and high-accuracy. Published version

Aim Ligation of the intersphincteric fistula tract and reinforcement with a bioprosthetic graft are two recently reported procedures that have shown promise in the treatment of anal fistula. This study was undertaken to validate combining ligation of the intersphincteric fistula tract plus bioprosthetic anal fistula plug and report our preliminary results and experience. Method Twenty-one patients with transsphincteric anal fistula were treated with ligation of the intersphincteric fistula tract plus concurrent bioprosthetic plug of the anal fistula. We evaluated healing time, fistula closure rate and postoperative anal function according to the Wexner continence score. Results No mortality or major complications were observed. Median operative time was 20 (range 15–40) min. After a median follow-up of 14 (range 12–15) months, the overall success rate was 95% (20/21), with a median healing time of 2 (range 2–3) weeks for external anal fistula opening and 4 (range 3–7) weeks for intersphincteric groove incision. Only 1 (5%) patient reported rare incontinence for gas postoperatively (Wexner score 1). Conclusions Ligation of the intersphincteric fistula tract plus a bioprosthetic anal fistula plug is an easy, safe, effective and useful alternative in the management of anal fistula. Further randomized controlled studies are necessary to better evaluate long-term results.

A metal-lined hollow-core fiber-based Raman probe extension kit is proposed in this Letter for in situ and sensitive ultramicro-analysis. A hollow-core fiber can confine light and fluid samples in its hollow core, with enhanced light–sample interaction. By using a homemade light coupling device with a glass window for liquid isolation, a 3.5-cm-long hollow-core fiber could mount on and connect to a Raman probe, with perfect light coupling efficiency. After full filling the hollow-core fiber chamber with a volume of 13 μL by using a syringe pump, it can act as an extension kit for an ordinary Raman probe and be used as a ultramicro-analysis tool for the sample of microfluidic chips. In order to enhance its sensitivity, a gold film coated fiber tip is inserted into the capillary, which can double the Raman signal received by reflecting pump light and Raman light. Finally, a detection limit of 5% for ethanol solution and an enhancement factor of two compared with direct detection of bulk sample volume are demonstrated. Above all, our device can be utilized as a Raman probe extension kit, which is suitable for rapid, sensitive, and in situ measurements for a few microliter level samples.

In this paper, we propose a Bayesian of inductive cognition algorithm based on Dirichlet process used in virtual reality multimedia information data classification. We present a Bayesian of inductive cognition algorithm framework model for classifying scenes in virtual reality multimedia data. The multimedia can switch between different shots, the unknown objects can leave or enter the scene at multiple times, and the scenes can be classified. The proposed algorithm consists of Bayesian inductive cognition part and Dirichlet process part. This algorithm has several advantages over traditional distance-based agglomerative classifying algorithms. Bayesian of inductive cognition algorithm based on Dirichlet process hypothesis testing is used to decide which merges are advantageous and to output the recommended depth of the scenes. The algorithm can be interpreted as a novel fast bottom-up approximate inference method for a Dirichlet process mixture model. We describe procedures for learning the model...

We theoretically analyze the generation of quadripartite continuous-variable entanglement, with different frequency, by cascaded nonlinear process in a quadruply resonant optical cavity. This process is realized by one optical parametric down-conversion operated below threshold cascaded by two sum-frequency generations in a quasiperiodic optical supperlattice. It shows that the signal, idler and two sum frequency modes are entangled according to the sufficient inseparability criterion proposed by van Loock and Furusawa. The quantum correlation spectra among these four modes versus normalized analysis frequency and nonlinear coupling coefficients are discussed as well in detail.

The production of quadripartite continuous-variable entanglement, with different frequency, is analyzed theoretically. This process is realized by parametric amplifier cascaded with a sum frequency generation in a quasiperiodically optical supperlattice, meanwhile, the nondegenerated optical parametric amplifier operated above threshold and the injection signal field with very small intensity is in coherent state. It shows that the four-partite of the pump, two subharmonic and the up-converted modes from the cavity is genuinely entangled according to the sufficient inseparability criterion proposed by Van Loock and Furusawa. Moreover, the entanglement characteristics versus different parameters are discussed as well in detail.

We present an approach to generating a tunable orange laser from 0.601 to 0.604 μm based on a quasi-periodically poled superlattice in LiTaO3 and a Q-switched 1.064 μm Nd:YVO4 laser as pump. The orange laser was generated in a cavity by a parametric process cascaded by a frequency mixing with a maximum output of 310 mW using 15 W pump power.

One promising technique for working toward practical photonic quantum technologies is to implement multiple operations on a monolithic chip, thereby improving stability, scalability and miniaturization. The on-chip spatial control of entangled photons will certainly benefit numerous applications, including quantum imaging, quantum lithography, quantum metrology and quantum computation. However, external optical elements are usually required to spatially control the entangled photons. Here we present the first experimental demonstration of on-chip spatial control of entangled photons, based on a domain-engineered nonlinear photonic crystal. We manipulate the entangled photons using the inherent properties of the crystal during the parametric downconversion, demonstrating two-photon focusing and beam-splitting from a periodically poled lithium tantalate crystal with a parabolic phase profile. These experimental results indicate that versatile and precise spatial control of entangled photons is achievable. Because they may be operated independent of any bulk optical elements, domain-engineered nonlinear photonic crystals may prove to be a valuable ingredient in on-chip integrated quantum optics.

Aperiodically poled nonlinear crystal can be used as a broadband continuous-variable entanglement source and has strong stability under perturbations. We study the conversion dynamics of the sum-frequency generation and the quantum correlation of the two pump fields in a chirped-structure nonlinear crystal using the quantum stochastic method. The results show that there exists a frequency window for the pumps where two optical fields can perform efficient upconversion. The two pump fields are demonstrated to be entangled in the window and the chirped-structure crystal can be used as a continuous-variable entanglement source with a broad response bandwidth.

we investigate the propagation and scattering of surface plasmon polaritons (SPPs) in a dual-periodical metal heterowaveguide based on the transfer matrix method and the finite-difference time-domain analysis (FDTD). In this structure, the resonance transmission mode with high with high-quality factors can be generated. By adjusting the structure parameters, center frequency, frequency interval and number of the modes can be flexibly tuned. The numerical simulation agrees well with the theoretical predication. Our results can be implied for the SPP-based wavelength division multiplexers and multi-channel light emitters. The structure can be applied to the multi-wavelength filters.

The study of phonon-polariton Raman scattering continues to be a challenge, in part because of the difficulty of measuring relatively low intensity of scattered signals. This paper reports the experimental results on phonon-polariton Raman scattering in a hexagonally poled $\mathrm{Li}\mathrm{Ta}{\mathrm{O}}_{3}$ crystal, showing the anti-Stokes and Stokes Raman signal intensities are significantly enhanced by cascading a couple of quasi-phase-matching processes where the coherent polariton fields are driven and the enhanced scattering signals are further amplified.

Background: Monitoring of iodine nutrition depends chiefly on the urinary iodine concentration in representative samples from the population. International groups have recommended school-age children as a convenient group for surveys, because of their accessibility and young age, but the relevance of this group to others, especially pregnant women, is not well established. Objective: The purpose was to compare different approaches to assessing iodine nutrition within communities, especially for pregnant and lactating women. Design: In an urban and a rural site from each of the 11 Chinese provinces, covering a wide geographic and socioeconomic range, we measured the iodine content of household salt and drinking water, the thyroid volume in school children, and the urinary iodine concentration in five population subsets; in some sites we also assessed iodine in breast milk and thyroid size in adult women. Results: The median urinary iodine concentrations for pregnant and lactating women were well below those ofthe schoolchildren from the same community in most study sites, the difference between medians, at overall level, being about 50 μg/l for the pregnant and 40μg/l for the lactating, respectively. When ranked by median urinary iodine concentrations at overall level, the order of the groups was: all infants, schoolchildren, women of childbearing age, lactating women and pregnant women in both urban and rural sites. This relative distribution was constant among the study sites. From it, we derived a relationship to predict the median values for other groups, based on the data of schoolchildren. The median iodine content of salt was 30.9 ppm in urban sites and 31.3 ppm in rural sites, respectively, close to the nationally mandated 35 mg/kg. Water had low iodine content (3.7 μg/l) in both urban and rural sites except in a rural site from Tianjin. Ultrasonography showed that 6.5% of 1329 children in urban sites and 5.3% of 1431 children in rural sites had thyroid enlargement. Breast milk had a median iodine content of 135.9 μg/l in the urban and 157.5 μg/l in the rural. The goiter prevalence by palpation was low (2.0%) among all women examined (3367), but higher in pregnant women (2.7%) than in lactating women or other adult women. Conclusions: An effective iodized salt program has brought iodine sufficiency to most of China, but pregnant women in some areas may still risk deficiency and need further supplements. We suggest other countries and international agencies pay more attention to pregnancy, where iodine deficiency has its worst consequences.

A new type of conical second-harmonic generation was discovered in a 2D chi((2)) photonic crystal-a hexagonally poled LiTaO3 crystal. It reveals the presence of another type of nonlinear interaction-a scattering involved optical parametric generation in a nonlinear medium. Such a nonlinear interaction can be significantly enlarged in a modulated chi((2)) structure by a quasi-phase-matching process. The conical beam records the spatial distribution of the scattering signal and discloses the structure information and symmetry of the 2D chi((2)) photonic crystal.

We theoretically investigate the long-wavelength optical properties of a plasmonic crystal composed of end-to-end gold nanorod dimers. The strong coupling between incident light and the electron oscillations inside the nanorods gives rise to a plasmon polariton, which can be analogous to the phonon polariton in an ionic crystal. Huang-Kun-like equations are employed to explore the underlying physical mechanism for both symmetrical and asymmetrical geometries. In the long wavelength limit, the macroscopic dielectric response of the proposed structure is deduced analytically. The polariton dispersion curve shows a typical anticrossing profile in the strong coupling regime and adjacent branches are separated by a Rabi splitting. The resultant polaritonic stop band is validated by the numerical simulations.

Aim To estimate the number of colon cancer patients in New South Wales (NSW) Australia requiring cancer care in the future. Methods Prevalence of first primary colon cancer was estimated and projected forward, by stage of clinical care (initial care, long-term survivors, monitoring, and last year of life), for 2007–2016. Then using data from a patterns of care study for colorectal cancer, we estimated the type and amount of treatments that will be needed by colon cancer patients in each stage of care. Finally, data on metachronous tumours or second primary colon cancers were used to estimate the additional number of patients who will require care. Results In NSW in 2006, there were 17 687 patients aged 18–84 years alive with a past diagnosis of colon cancer. By 2016, this number will have increased to 22 262. The expected numbers of patients vary by stage of care with the majority in the monitoring stage (41.4%) or being long-term survivors (40.7%). There will be at least 1389 men and 1135 women requiring initial surgery for colon cancer in 2016. Of these 431 men and 352 women will also require adjuvant chemotherapy. In addition, there will be 741 patients with metachronous tumours or second primary colon cancers who will also need care in 2016 with 56% of them in the monitoring stage. Conclusions These estimates reveal that in NSW the numbers of colon cancer patients requiring care for colon cancer are projected to rise by over 25% from 2006 to 2016.

Background Estimates of the fraction of patients cured from cancer provide important information to both patients and clinicians. But how reliable are the estimates? Methods Three statistical approaches, based on similar assumptions that a fraction of patients will be cured from cancer, were used to estimate the fraction cured. The first approach was CANSURV software and the second was developed by De Angelis et al (1999), both using grouped survival data. The third was published by Lambert et al (2007), requiring individual patient records. All three approaches fit mixture cure models; and CANSURV and Lambert9s implementation use maximum likelihood, while De Angelis9 implementation is based on non-linear least squares. Cansurv is a standalone program whereas the other approaches were implemented using SAS and Stata respectively. SEER-9 data for rectal cancer were used to illustrate the methods. Results As shown in the Abstract P1-63 table 1, estimates of the cure fraction were similar for the two approaches requiring grouped survival data while Lambert9s method provided lower a estimate for patients with localised disease. Discussion The three approaches provided similar estimates of the cure fraction for patients with regional and distant stage at diagnosis, however there are considerable differences in the estimates for patients with localised disease. Estimates of the cure fraction appear to depend on the choice of statistical model even when the underlying assumptions are very similar.

Simultaneous generation of noncollinear red, green, and blue light from a single hexagonally poled lithium tantalate is reported. It results from the frequency self-doubling optical parametric amplification process, a process of second-order harmonic generation cascaded optical parametric amplification in a single-pass setup. The temperature and spectrum detuning characters of each cascaded quasi-phase-matching process are studied. This unique red-green-blue light source has potential applications in laser display and other laser industries.