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Movement of marine debris is transboundary and complex, travelling vast distances and accumulating on shorelines. These marine debris wash ashore as stranded beach litter. The objective of this work is to identify release sources of marine debris accumulated along the Singapore coastlines collected by applying a time-backward adjoint marginal sensitivity method and citizen science data of stranded beach litter by a voluntary beach clean-up group. A popular tourist hotspot on the opposite shore was estimated as a possible release source contributing to the marine debris accumulation. This analytical result was validated by population density, industry types, rainfall, and inference from product packaging labels. The use of the citizen science data also illustrated potential as a data source for baseline monitoring and long-term cross-border research that influence policymaking. Future research can be conducted in an expanded domain, considering monsoon effects and instantaneous release events. • The adjoint method was used to detect marine debris sources near Singapore. • Volunteer beach clean-up data were successfully applied to the adjoint method. • A popular tourist hotspot on the opposite shore was estimated as a release source. • The results were validated by population, industry, rainfall, and packaging labels. • The use of citizen science data suggests its influence on policy-making. [ABSTRACT FROM AUTHOR]

Evidence of the influence of prenatal phthalate exposure on childhood longitudinal obesity markers is limited. Nested on the Ma'anshan birth cohort study, 990 mother-daughter pairs were included. Seven phthalate metabolites were determined in urine collected in each trimester. Each child underwent a physical examination from birth to 6 years of age twelve times. Latent class growth models were used to identify three trajectories of girls' body mass index (BMI). Logistic regression, quantile g-computation and Bayesian kernel machine regression models analyzed the relationships of prenatal exposure to individual and mixed phthalates with girls' body mass index (BMI) trajectory. Compared to the "lowest trajectory" class, prenatal average concentrations of mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP, OR crude = 2.095, 95 % CI = 1.014–4.328) and di(2-ethylhexyl) phthalate (DEHP, OR crude = 2.336, 95 % CI = 1.022–5.338) during pregnancy were associated with an increased probability of being in the "highest trajectory" class. The average concentration of DEHP (OR crude = 1.879, 95 % CI = 1.002–3.522) was associated with an increased probability of being in the "moderate trajectory" class. Stratified analyses by trimester of pregnancy mainly showed that third-trimester exposure to monoethyl phthalate (MEP, OR adjusted = 1.584, 95 % CI = 1.094–2.292), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP, OR adjusted = 2.885, 95 % CI = 1.367–6.088), MEHHP (OR adjusted = 2.425, 95 % CI = 1.335–4.407), DEHP (OR adjusted = 2.632, 95 % CI = 1.334–5.193) and high molecular weight phthalate (OR adjusted = 2.437, 95 % CI = 1.239–4.792) was associated with an increased probability of being in the "highest trajectory" class. However, the mixture of phthalates was not significantly related to the girl's BMI trajectory. In conclusion, in utero exposure to phthalates, including MEP and DEHP metabolites (MEHHP and MEOHP), was significantly associated with early childhood high BMI trajectories in girls. The third trimester of pregnancy seemed to be the window of vulnerability to phthalate exposure for girls' high BMI trajectory at periods of prenatal development. No evidence supported a significant relationship between combined exposure to phthalate metabolites and girls' high BMI trajectory. [Display omitted] • Up to three urine samples obtained during pregnancy were used to analyze phthalates. • Latent class growth model was used to identify three trajectories of girl's BMI. • Prenatal some phthalate metabolites were related to BMI trajectory in girls aged 0–6. • Third trimester of pregnancy seemed to be the window of vulnerability to phthalates. • Mixture of phthalate metabolites was not associated with the girl's BMI trajectory. [ABSTRACT FROM AUTHOR]

The Y 0.5− x Gd 0.35 Eu 0.15 Bi x NbO 4 (0 ≤ x ≤ 0.30) and Y 0.35 Gd 0.35 Eu 0.15 Bi 0.15 Nb 1− y P y O 4 (0 ≤ y ≤ 0.20) phosphors have been synthesized by the conventional solid-state reaction. For these Y 0.5− x Gd 0.35 Eu 0.15 Bi x NbO 4 (0 ≤ x ≤ 0.30) samples, the emission increases and then decreases with increasing Bi content, and the maximum emission is achieved when x is 0.18. As for the Y 0.35 Gd 0.35 Eu 0.15 Bi 0.15 Nb 1− y P y O 4 (0 ≤ y ≤ 0.20) samples, the emission and excitation intensities are both varied with the P doping content. The strongest intensity is obtained in the case of y = 0.15. These results indicate that the Bi dopant acts as one sensitizer and enhances the photoluminescence intensity. The introduction of PO 4 3− also plays an important role in the photoluminescence properties of the investigated samples. The relevant mechanism has been also presented. [ABSTRACT FROM AUTHOR]

Taking the MnO cluster as a model system, the spin-polarized transport properties of the small cluster system were systematically probed. The theoretical investigations are based on density-functional theory and non-equilibrium Green's functional method. The equilibrium transport mechanism is illustrated by the band structure of the electrode, the electronic structure of the MnO cluster and the coupling between the cluster and the electrodes. To well understand the non-equilibrium mechanisms, one straightforward and simple band-matching model was proposed. Moreover, such a band-matching model can be extended to well illustrate the transport properties of other nano-scale systems. [ABSTRACT FROM AUTHOR]

YEuVO: xBi ( x = 0, 0.02, 0.04, 0.06, 0.08, and 0.10 mol) six photoluminescence films were deposited on glass substrates by sol-gel spin-coating method. Their morphology and optical property were investigated. The micrographs for the six samples have no change with Bi doping. The emission spectra result shows that a dominant red emission peak at 620 nm, which is due to the Eu electric dipole transition of D → F, is observed under excitation wavelengths 254 nm. Furthermore, with the content of Bi increasing from 0 to 0.08 mol, the emission intensity of samples strengthens and reaches a maximum at x = 0.08 mol, then decreases with the doping content to 0.10 mol. [ABSTRACT FROM AUTHOR]