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Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
Two-dimensional particle-in-cell (PIC) simulations have been used to investigate the interaction between a laser pulse and a foil exposed to an external strong longitudinal magnetic field. Compared with that in the absence of the external magnetic field, the divergence of proton with the magnetic field in radiation pressure acceleration (RPA) regimes has improved remarkably due to the restriction of the electron transverse expansion. During the RPA process, the foil develops into a typical bubble-like shape resulting from the combined action of transversal ponderomotive force and instabilities. However, the foil prefers to be in a cone-like shape by using the magnetic field. The dependence of proton divergence on the strength of magnetic field has been studied, and an optimal magnetic field of nearly 60 kT is achieved in these simulations.
Mosquitoes are haematophagous vectors for hundreds of pathogenic viruses that are aetiological agents of human diseases. In nature, mosquito-borne viruses maintain a lifecycle between mosquitoes and vertebrate animals. Viruses are acquired by a naive mosquito from an infected host by blood meals and then propagate extensively in the mosquito's tissues. This mosquito then becomes a virus reservoir and is competent to transmit the viruses to a naive vertebrate host through the next blood meal. To survive in and efficiently cycle between two distinct host environments, mosquito-borne viruses have evolved delicate and smart strategies to comprehensively exploit host and vector factors. Here, we provide an update on recent studies of the mechanisms of virus survival in, acquisition and transmission by mosquitoes.
Previous studies in schizophrenia revealed abnormalities in the cortico-cerebellar-thalamo-cortical circuit (CCTCC) pathway, suggesting the necessity for defining thalamic subdivisions in understanding alterations of brain connectivity.
To parcellate the thalamus into several subdivisions using a data-driven method, and to evaluate the role of each subdivision in the alterations of CCTCC functional connectivity in patients with schizophrenia.
There were 54 patients with schizophrenia and 42 healthy controls included in this study. First, the thalamic structural and functional connections computed, based on diffusion magnetic resonance imaging (MRI, white matter tractography) and resting-state functional MRI, were clustered to parcellate thalamus. Next, functional connectivity of each thalamus subdivision was investigated, and the alterations in thalamic functional connectivity for patients with schizophrenia were inspected.
Based on the data-driven parcellation method, six thalamic subdivisions were defined. Loss of connectivity was observed between several thalamic subdivisions (superior-anterior, ventromedial and dorsolateral part of the thalamus) and the sensorimotor system, anterior cingulate cortex and cerebellum in patients with schizophrenia. A gradual pattern of dysconnectivity was observed across the thalamic subdivisions. Additionally, the altered connectivity negatively correlated with symptom scores and duration of illness in individuals with schizophrenia.
The findings of the study revealed a wide range of thalamic functional dysconnectivity in the CCTCC pathway, increasing our understanding of the relationship between the CCTCC pathway and symptoms associated with schizophrenia, and further indicating a potential alteration pattern in the thalamic nuclei in people with schizophrenia.
To investigate the morphology and dimensions of the vestibular aqueduct on axial, single-oblique and double-oblique computed tomography images.
The computed tomography temporal bone scans of 112 patients were retrospectively evaluated. Midpoint and opercular measurements were performed using axial, single-oblique and double-oblique images. Morphometric analyses were also conducted. The vestibular aqueduct sizes on axial, single-oblique and double-oblique images were compared.
At the midpoint, the mean (± standard deviation) vestibular aqueduct measured 0.61 ± 0.23 mm, 0.74 ± 0.27 mm and 0.82 ± 0.38 mm on axial, single-oblique and double-oblique images, respectively; at the operculum, the vestibular aqueduct measured 0.91 ± 0.30 mm, 1.11 ± 0.45 mm and 1.66 ± 1.07 mm on the respective images. The co-efficients of variation of the vestibular aqueduct measured at the midpoint were 37.4 per cent, 36.5 per cent and 47.5 per cent on axial, single-oblique and double-oblique images, respectively; at the operculum, the measurements were 33.0 per cent, 40.5 per cent and 64.5 per cent. Regarding morphology, the vestibular aqueduct was fissured (33.5 per cent), tubular (64.3 per cent) or invisible (2.2 per cent).
The morphology and dimensions of the vestibular aqueduct were highly variable among axial, single-oblique and double-oblique images.
The current measures of cognitive functioning in adulthood do not indicate a long-term association with prenatal exposure to the Dutch famine. However, whether such association emerges in China is poorly understood. We aimed to investigate the potential effect of prenatal exposure to the 1959–1961 Chinese famine on adult cognitive impairment. We obtained data from the Second National Sample Survey on Disability implemented in thirty-one provinces in 2006, and restricted our analysis to 387 093 individuals born in 1956–1965. Cognitive impairment was defined as intelligence quotient (IQ) score under 70 and IQ of adults was evaluated by the Wechsler Adult Intelligence Scale – China Revision. Famine severity was defined as excess death rate. The famine impact on adult cognitive impairment was estimated by difference-in-difference models, established by examining the variations of famine exposure across birth cohorts. Results show that compared with adults born in 1956–1958, those who were exposed to Chinese famine during gestation (born in 1959–1961) were at greater risk of cognitive impairment in the total sample. Stratified analyses showed that this effect was evident in males and females, but only in rural, not in urban areas. In conclusion, prenatal exposure to famine had an enduring deleterious effect on risk of cognitive impairment in rural adults.
Dietary energy density (ED) might have influences on body composition. We therefore examined whether ED is associated with body composition among Chinese adults.
We collected dietary data through validated two-day 24 h recalls. ED, defined as the amount of energy per unit weight of food consumed, was calculated based on five methods. Multiple linear regression analyses were performed to explore the associations between ED and body composition parameters, including BMI, fat mass index (FMI), fat-free mass index (FFMI), percentage body fat (%BF) and waist circumference (WC).
Chinese adults (n 1933) in 2013.
After adjusting the covariates, all ED definitions were positively associated with BMI, FMI, FFMI, %BF and WC among women (P<0·01). In men, however, ED with foods only was positively associated with BMI, FMI, FFMI and %BF (P<0·05), but not with WC (P=0·07); we also found null associations between ED with foods and all beverages and body composition among men. Additionally, ED contributed to higher increases of body composition in women than in men (P<0·01).
The present study supports the positive association between ED and body composition among adults in Southwest China, in which beverages may play an important role.
The objective of this Research Communication was to use polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analysis to investigate a region of the bovine TLR4 gene (TLR4) in pasture-fed New Zealand (NZ) Holstein-Friesian × Jersey (HF × J) cross dairy cows and to determine whether gene variation was associated with milk production traits. Genetic variation was observed, with two variants (A and B) containing a single nucleotide polymorphism (SNP) (c.2021C/T) that was non-synonymous and putatively results in a p.Thr674Ile substitution in the transmembrane/cytoplasmic domain of TLR4. Variant A was associated with higher milk yields, but lower milk fat percentages, whereas B was associated with lower milk yields, but higher fat and protein percentages. Cows of genotype AA produced more milk than AB or BB cows, but the milk produced by AA cows contained less fat than AB or BB cows.
Dome A is the highest ice feature in Antarctica, at over 4000 m a.s.l., and overlies the Gamburtsev mountains. It is believed that deep ice-core drilling in this area may reveal the oldest ice in Antarctica, providing an unparalleled paleoclimate record in excess of 1 Ma, and perhaps going back as far as 1.2 Ma (Xiao and others, 2008). However, little is known about this area because its height and distance from the coast and scientific stations makes access difficult.
We identified human paleodietary changes from inhabitants of the Guanzhong basin since 8000 BP, based on published carbon and nitrogen isotopic measurements on bones, fauna and plant remains. We also directly measured 14C ages, δ13C and δ15N values from bones unearthed at the Zhouyuan site, west of Guanzhong, in order to reconstruct paleodietary changes of the ancient inhabitants. We found that during the Laoguantai period, animal foods were the main source of nourishment with supplementary plant-derived foods. After this period, plant-derived foods became the main food source, with supplementary animal sources. The development of dry farming led to increased consumption of foxtail millet and broomcorn millet. This trend persisted and marked a fundamental shift from hunting, gathering, and fishing to farming and animal domestication. The dietary trends of the ancient inhabitants also show pronounced regional differences through time. The use of domestic animals was proportionally higher in the eastern part of the Guanzhong region, while wild animals were more common in the west.
The motion of the binary pulsar PSR J0751+1807 is assumed to satisfy the gravitational two-body equation (Barker and O’Connell 1975). Then by studying the motion of the binary system from initial state which determined by 3 precession phases of angular momenta (the orbit, the pulsar and the companion star) to the current state which determined by the observations on the orbital inclination. The spin angular momenta of the pulsar and the companion star are obtained.
In this paper, we introduce and study a new method for solving inverse source problems, through a working model that arises in bioluminescence tomography (BLT). In the BLT problem, one constructs quantitatively the bioluminescence source distribution inside a small animal from optical signals detected on the animal's body surface. The BLT problem possesses strong ill-posedness and often the Tikhonov regularization is used to obtain stable approximate solutions. In conventional Tikhonov regularization, it is crucial to choose a proper regularization parameter for trade off between the accuracy and stability of approximate solutions. The new method is based on a combination of the boundary condition and the boundary measurement in a parameter-dependent single complex Robin boundary condition, followed by the Tikhonov regularization. By properly adjusting the parameter in the Robin boundary condition, we achieve two important properties for our new method: first, the regularized solutions are uniformly stable with respect to the regularization parameter so that the regularization parameter can be chosen based solely on the consideration of the solution accuracy; second, the convergence order of the regularized solutions reaches one with respect to the noise level. Then, the finite element method is used to compute numerical solutions and a new finite element error estimate is derived for discrete solutions. These results improve related results found in the existing literature. Several numerical examples are provided to illustrate the theoretical results.
Based on a dynamic open-economy macroeconomic model, this paper analyzes the motive for foreign reserve accumulation in fast-growing emerging economies. The demand for foreign reserves stems from the interaction between productivity growth and underdevelopment of the domestic financial market. As domestic firms are credit-constrained, domestic saving instruments are necessary to increase their retained earnings in order to invest in capital. The central bank plays the role of a financial intermediary and provides liquid public bonds while investing the bond proceeds abroad in the form of foreign reserves. Foreign reserve accumulation is thus part of a catching-up strategy in an economy facing financial frictions. During economic transition, foreign reserve accumulation is proved to be welfare-improving as long as private capital flows are controlled. This joint strategy enables the central bank to channel sufficient external funding to the domestic economy while keeping domestic interest rates under control to cope with positive productivity shocks.
Multi-band metamaterial absorber (MA) was proposed at the microwave frequency ranges, which were composed of cave-cross resonator (CCR) with different geometric dimensions, dielectric substrate and continuous metal film. Microwave experiments demonstrated the maximum absorptivity of single CCR structure to be about 99% around 9 GHz. Numerical simulations confirm that the MA could achieve very high absorptivity at wide angles of incidence for both transverse electric (TE) wave and transverse magnetic (TM) wave. Importantly, numerical simulations demonstrate that the MA could achieve perfect multi-band absorption by assembling the multi-CCR structure with different geometric parameters in a coplanar.
We develop Si-based nano-photonic devices for the control of light at the nano-scales. We design high quality (Q) factor photonic crystal nanobeam cavities for a variety of Si compatible materials with low index, such as silicon rich oxide and silicon nitride, all with Q > 9,000 and small mode volumes. We apply these cavity designs to active materials such as Sinanocrystal doped silicon oxide and Er doped silicon nitride. By placing emitters in these cavities, we demonstrate that the cavity enhances emission processes. We show that the free carrier absorption process is greatly enhanced in the nanobeam cavities at both room and cryogenic temperatures. In addition, we demonstrate that nanobeam cavities made of Er-doped amorphous silicon nitride have enhanced absorption and gain characteristics compared to earlier designs that included silicon in the cavity. Because of the reduced losses, we observe linewidth narrowing and material transparency at both room temperature and cryogenic temperatures.
Ba0.8Sr0.2TiO3 thin films that are suitable for infrared detector applications have been prepared with a sol-gel process using a highly diluted precursor solution. Columnar structure with grain size close to 200 nm was obtained with layer-by-layer homoepitaxy due to a very small thickness of individual layer. The measured pyroelecrtic coefficient is larger than 3.1×10划4 C/m2K at the temperatures ranging from 10 to 26 °C and reaches the maximum value of 4.1×10划4 C/m2K at 16.8 °C. The infrared detectivity of 4.6×107 cmHz1/2W划1 has been obtained at 19 °C and 10 Hz in the Ba0.8Sr0.2TiO3 films deposited on thick (500 μm) platinum coated silicon substrates. The better infrared response can be expected by the improvement in the thermal isolation of pyroelectric element and the electrode materials.
The excitation intensity dependency of nanocrystallite Si (nc-Si) related micro-photoluminescence (μ-PL) from the multi-recipe Si-implanted quartz is characterized. The μ-PL at 724 nm contributed by nc-Si with 3-4 nm diameter is maximized after annealing at 1100°C for 3 hours. By increasing the excitation intensity from 10 kW/cm2 to 300 kW/cm2, the μ-PLs of 1-hr and 3-hr annealed quartz significantly red-shift from 723 nm to 725 nm and from 724 nm to 735 nm, respectively. This can be explained by the anomalous quantum stark effect due to a surface electric field oriented from photo-ionized nc-Si dots to quartz surface. After 1-hr illumination at power of 300 kW/cm2, the μ-PL peak wavelength of 3-hr annealed sample is further red-shifted by 2.5 nm. By measuring the accumulated surface charges built up during optical excitation process, the correlation between excitation-intensity dependent PL wavelength red-shift and the photo-ionized nc-Si surface electric-field related quantum stark effect is primarily elucidated.
The electrical properties of poly(vinyl alcohol) complexed with phosphoric acid have been studied. It is found that the conductivity increases with the concentration of the acid, and also increases with time if the sample is exposed to the air, which is interpreted in terms of glass transition temperature. A.C. impedance measurement and polarization experiment show that this proton-conducting polymer is a promising candidate for electrochromic display. It is also found that some plasticizers, such as glycerol and ethylene-glycol are effective for improving its conductivity.
The highly electroactive thiokol rubber (TR)/ conjugated polymer (eg. polyaniline (PAn) or polypyrrole (PPy)) composite films were prepared by electropolymenzation deposition via one-step process in the electrolytic solutions containing aniline or pyrrole and TR oligomer. The electrocatalysis of PAn or PPy for the electrodepolymerization (reduction)- electropolymenzation (oxidation) reaction of TR in the interface between PAn or PPy and TR is determined by cyclic voltammograms. The differeme between the oxidation potential and the reduction potential is 0.05V and 0.36V or less for TR/PAn and TR/PPy composite films, respectively The chemical bands between the nitrogen atoms of PAn or PPy and the mercaptan groups of TR (oligomer) are formed in the electropolymenzation process that is indicated by XPS. The conductivities of TR/PAn and TR/PPy composite films and the stability of the cells consisting of those films are remarkably improved after electrochemical reduction with addition of a suitable conducting carbon black.