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Evidence on the association between maternal Hb concentration and preterm birth (PTB) risk is inconclusive. This paper aimed to explore whether women with anaemia or high Hb level before pregnancy would be at higher risk of PTB. We conducted a population-based cohort study with 2 722 274 women aged 20–49 years, who participated in National Free Pre-Pregnancy Checkups Project between 2013 and 2015 and delivered a singleton before 2016 in rural China. Logistic models were used to estimate OR and 95 % CI after adjusting for confounding variables. Restricted cubic spline models were applied to evaluate the dose–response relationships. A total of 192 819 (7·08 %) women had preterm deliveries. Compared with women with Hb of 110–149 g/l, the multivariable-adjusted OR for PTB was 1·19 (95 % CI 0·98, 1·44) for women with Hb<70 g/l, 1·01 (95 % CI 0·97, 1·03) for 70–99 g/l, 0·96 (95 % CI 0·95, 0·98) for 100–109 g/l, 1·04 (95 % CI 1·01, 1·06) for 150–159 g/l, 1·11 (95 % CI 1·05, 1·17) for 160–169 g/l and 1·19 (95 % CI 1·11, 1·27) for ≥170 g/l, respectively. The multivariable-adjusted OR for very PTB (VPTB) was 1·07 (95 % CI 1·03, 1·12) and 1·06 (95 % CI 1·01, 1·12) for women with Hb <110 and ≥150 g/l, compared with those with Hb of 110–149 g/l, respectively. Our study identified a U-shaped relationship between maternal preconception Hb concentration and PTB risk. Both preconception anaemia and high Hb level can significantly increase VPTB risk. Appropriate intervention for women with abnormal Hb levels before pregnancy is very necessary.

Flower-like AgI/Bi5O7I hybrid photocatalysts were fabricated via a hydrothermal method and the subsequent heating process with AgI/Bi4O5I2 as the intermediate. X-ray powder diffraction, Raman, X-ray photoelectron spectroscopy, diffuse reflectance spectra, scanning electron microscopy, transmission electron microscopy, photoluminescence, and electrochemical methods were used to reveal the structure, elemental content, morphology, and charge separation capabilities of the as-prepared samples. The photocatalytic test showed that the AgI/Bi5O7I composites own much higher photoactivity than pure AgI and Bi5O7I. Based on the result of XPS analysis, the composite is believed to be the Ag/AgI/Bi5O7I system. Due to the suitable band potentials of AgI and Bi5O7I, the ternary system can form a heterojunction structure which works in a Z-scheme mechanism with Ag nanoparticles as the transfer media. The guided charge transfer in the composite prolongs the life time of charge carriers and eventually leads to the high photocatalytic activity of AgI/Bi5O7I. Additionally, the flower-like structure of the composite also contributes to the photocatalytic reaction.

Graphitic carbon nitride (g-C3N4) is considered as a promising heterogeneous catalyst for photocatalytic H2 evolution from water under visible light illustration, and its photocatalytic performance could be controlled through its texture and optical/electronic properties. Herein, we present a facile one-step heating method for the synthesis of B/P/F doped g-C3N4 photocatalysts (BCN, PCN, and FCN). The prepared photocatalysts were characterized by XRD, SEM, UV-vis absorption, FTIR, BET, XPS, PL, and photocurrent measurement. The results show that the B/P/F doping increased the interplanar stacking distance of g-C3N4, enlarged the optical absorption range, and improved the photocatalytic activity of H2 evolution. FCN exhibits the highest photocatalytic activity, followed by BCN, and PCN that has the lowest performance. This work studies the doping effects of the nonmetal elements on the photocatalytic activities, the electronic structures as well as the band gaps of g-C3N4, to provide a feasible modification pathway to design and synthesize highly efficient photocatalysts.

An exact analytical solution to the three-dimensional elasticity problem for a transversely-isotropic composite layer is constructed by making use of the direct integration method along with the Fourier double-integral transform. The original problem is reduced to a system of governing partial-differential equations for separate stress-tensor components. The governing equations are accompanied with corresponding local and integral boundary conditions, obtained on the basis of the original local boundary conditions imposing the normal and shearing forces on the limiting planes of the layer. The numerical analysis of the obtained solution is presented for certain transversely-isotropic composite materials.

OBJECTIVES/SPECIFIC AIMS: Research on cancer difference is of significant scientific and practical value. For leukemia, the survival disadvantage of the Blacks has been suggested in multiple studies. However, the existing epidemiologic analysis has multiple technical limitations. The goal of this study is to more accurately quantify so as to better understand different sources of racial differences in leukemia survival. METHODS/STUDY POPULATION: A new statistical method, which is based on robust regression and resampling, is developed. Data are obtained from the SEER (Surveillance, Epidemiology, and End Results) database. Using the “classic” epidemiologic methods as well as the new method, analysis is conducted on the prognosis of 4 leukemia subtypes (ALL, CLL, AML, and CML) for 4 major racial groups (White, non-Hispanic White, Black, and Asian and Pacific Islander). RESULTS/ANTICIPATED RESULTS: After effectively removing differences caused by the observed clinicopathological and demographic factors, the survival disadvantage of the Blacks persists for the following patient groups: ALL and age>14, CLL and age>14, and ALL and age≤14. The quantitative results are significantly different from those from classic epidemiologic analysis. Such observed racial differences are more attributable to the unobserved risk factors and cancer disparity. DISCUSSION/SIGNIFICANCE OF IMPACT: This study provides a more effective and more direct quantification of racial difference in leukemia prognosis. The survival disadvantage of the Blacks which is observed for certain subtypes/age groups deserves further attention but should not be overstated. More data collection and analysis are needed to more accurately decipher racial differences in leukemia and other cancer types.

This research was designed for the first time to investigate the photocatalytic activities of MoO3/g-C3N4 composite in converting CO2 to fuels under simulated sunlight irradiation. The composite was synthesized using a simple impregnation-heating method and MoO3 nanoparticles was in situ decorated on the g-C3N4 sheet. Characterization results indicated that the introduction of MoO3 nanoparticles into g-C3N4 fabricated a direct Z-scheme heterojunction structure. The effective interfacial charge-transfer across the heterojunction significantly promoted the separation efficiency of charge carriers. The optimal CO2 conversion rate of the composite reached 25.6 μmol/(h gcat), which was 2.7 times higher than that of g-C3N4. Additionally, the synthesized MoO3/g-C3N4 also presented excellent photoactivity in RhB degradation under visible-light irradiation.

Structural distortions at the nanoscale are delicately linked with many exotic properties for ferroic thin films. Based on advanced aberration corrected scanning transmission electron microscopy, we observe BiFeO3 thin films with variant tensile strain states and demonstrate at an atomic scale the interplay of intrinsic spontaneous structural distortions with external constraints. Structural parameters (the rhombohedral distortion and domain wall shear distortion) under zero (BiFeO3/GdScO3) and 1.5% (BiFeO3/PrScO3) lateral strain states are quantitatively analyzed which are suppressed within a few unit cells near the film/substrate interfaces. In particular, an interfacial layer with asymmetrical lattice distortions (enhanced and reduced out-of-plane lattice spacing) on the two sides of 109° domain wall is resolved. These structural distortions near the film/substrate interface in ferroic thin films reveal intense tanglement of intrinsic distortions of BiFeO3 with external boundary conditions, which could provide new insights for the development of nanoscale ferroelectric devices.

Al–(12, 20, 35 wt%)Si alloys were fabricated using powder metallurgy process involving hot pressing followed by hot extrusion. The effect of Si content on the microstructure [by scanning electron microscopy], the mechanical properties (hardness and tensile tests), and the thermal expansion behavior were studied in detail, respectively. Due to the friction between the Si phase and the matrix, as well as the diffusion of the Si atoms, the Si phase becomes a particulate shape after hot extrusion, and the size increases with increasing Si content. The mechanical strength increases, whereas, the elongation decreases with increasing the Si content from 12 to 35 wt%, which lead to a variation of the fracture mechanism from ductile to brittle failure. The coefficient of thermal expansion (CTE) decreases with increasing Si content as a result of restriction of Si on the Al matrix, and the measured CTE value is in good agreement with the Turner model below 573 K.

In magnetically confined plasma research, the understandings of small and large perturbations at equilibrium are both critical for plasma controlling and steady state operation. Numerical simulations using original MHD model can hardly give clear picture for small perturbations, while non-conservative perturbed MHD model may break conservation law, and give unphysical results when perturbations grow large after long-time computation. In this paper, we present a nonlinear conservative perturbed MHD model by splitting primary variables in original MHD equations into equilibrium part and perturbed part, and apply an approach in the framework of discontinuous Galerkin (DG) spatial discretization for numerical solutions. This enables high resolution of very small perturbations, and also gives satisfactory non-smooth solutions for large perturbations, which are both broadly concerned in magnetically confined plasma research. Numerical examples demonstrate satisfactory performance of the proposed model clearly. For small perturbations, the results have higher resolution comparing with the original MHD model; for large perturbations, the non-smooth solutions match well with existing references, confirming reliability of the model for instability investigations in magnetically confined plasma numerical research.

The effect of nitrogen gas addition in Ar-based double-layer shielding gas on the impact toughness of welded ultra-ferritic stainless steel during an autogenous gas tungsten arc welding (GTAW) process was investigated. The nitrogen behavior was proposed. The microstructure, mechanical properties, and fracture surface morphology of the weld metals have been evaluated. More equiaxed crystals, refined grain, narrow HAZ width, and increased microhardness were produced with nitrogen addition. Experimental findings indicated that nitrogen diffused into HAZ and dissolved into weld pool. The solute distribution was changed thus bringing significant constitutional supercooling and decreased temperature gradient of weld pool, which contributed to fine microstructure. Impact toughness at room temperature was enhanced from 2J to 9J (welds), 5J–13J (HAZ). Ductile fracture zone was produced about 0.3–0.5 mm thickness distance from the weld surface. A significant increased impact toughness of weld metal was due to the refinement of microstructure and element addition.

Seven-band grouper (Hyporthodus septemfasciatus) is a commercial rocky reef fish in East Asia that has been regarded as a promising species for aquaculture. To investigate the broodstock contributions to offspring for the sustainability of fry production, 62 individuals of H. septemfasciatus from two broodstocks and one offspring population were analysed using fluorescent-AFLP. A total of 602 bands were amplified and 70.10% of them were polymorphic. The numbers of polymorphic loci were 308 (P broodstock I = 55.50%) and 356 (P broodstock II = 63.12%) in the two broodstocks, and 294 (P offspring = 52.88%) in the offspring, respectively. The average values of Shannon diversity index (I) and expected heterozygosity (H) were higher in the broodstock (I broodstock I = 0.281, I broodstock II = 0.244, H broodstock I = 0.185, H broodstock II = 0.161) than those in the offspring (I offspring = 0.243, H offspring = 0.161). AMOVA and FST analyses showed that significant genetic differentiation between broodstock and offspring populations, and limited effective broodstock population size has contributed to the offspring. Both STRUCTURE and Principal Coordinates Analysis (PCoA) also showed the three populations composed of two stocks and most offspring individuals (95.0%) only originated from 44.0% of the individuals of broodstock I, which may have negative effects on sustainable fry production. Therefore, genetic variation between broodstock and offspring should be monitored, and large effective size of broodstock should be employed to ensure the success of commercial breeding programmes. Our data provide a useful genetic basis for future planning of sustainable culture and management of H. septemfasciatus.

Potassium titanyl phosphate crystals in both x-cut and z-cut were irradiated with 185 MeV Au ions. The morphology of the resulting ion tracks was investigated using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). SAXS measurements indicate the presence of cylindrical ion tracks with abrupt boundaries and a density contrast of 1 ± 0.5% compared to the surrounding matrix, consistent with amorphous tracks. The track radius depends on the crystalline orientation, with 6.0 ± 0.1 nm measured for ion tracks along the x-axis and 6.3 ± 0.1 nm for those along the z-axis. TEM images in both cross-section and plan-view show amorphous ion tracks with radii comparable to those determined from SAXS analysis. The protruding hillocks covering the sample surface detected by AFM are consistent with a lower density of the amorphous material within the ion tracks compared to the surrounding matrix. Simulations using an inelastic thermal-spike model indicate that differences in the thermal conductivity along the z- and x-axis can partially explain the different track radii along these directions.

Picoeukaryotes (<2–3 μm) perform key roles for the functioning of marine ecosystems, but little is known regarding the composition and diversity of picoeukaryotes in aquaculture areas. In this study, the Illumina MiSeq platform was used for sequencing the V4 variable region within the 18S rDNA gene to analyse genetic diversity and relative abundance of picoeukaryotic communities in the Qinhuangdao scallop cultivation area of the Bohai Sea. The community was dominated by three super groups, the alveolates (54%), stramenopiles (41%) and chlorophytes (3%), and three groups, dinoflagellates (54%), pelagomonadales (40%) and prasinophytes (3%). Furthermore, a contrasting station with open water away from the eutrophic aquaculture area was chosen. The communities collected from the two stations exhibited significant differences, with higher diversity in the aquaculture area. These results provide the first snapshot of the picoeukaryotic diversity in surface waters of the Qinhuangdao scallop cultivation area, and basic data for future studies on picoeukaryote community in an aquaculture region.

To investigate the effects of cold rolling on the microstructure, the precipitation behavior and the morphology of δ-phase, Inconel 718 alloy samples with different cold rolling reductions were aged for different periods at temperatures range from 850 °C to 1000 °C. Detailed microstructural observations and quantitative measurements were conducted to characterize the evolution of the δ-phase during aging. The results show that the microstructure consists of large deformed grains as a result of a slow static recovery at the low aging temperatures (850 and 900 °C); whereas the austenite matrix is fully recrystallized at the high aging temperatures (950 and 1000 °C). It is also found that the amount of δ-phase and the number density of spherical δ-phase particles increase with the increase in the degree of cold rolling both at low and high aging temperatures. With respect to different microstructural changes for the cold-rolled samples at the low or the high aging temperatures, two distinct mechanisms have been, respectively, introduced to interpret the changes in the precipitation behavior and the appearance of δ-phase.