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Organic polymeric flocculants are commonly used in improving dredged sludge dewaterability, but less attention has been paid to residual water quality. In this paper, the effects of cationic etherified starch (CS) and poly-dimethyl diallyl ammonium chloride (PDDA) on dredged sludge dewatering efficiency and residual water quality of Baiyangdian lake were comprehensively investigated and evaluated by analytic hierarchy process (AHP). The results indicated that PDDA had stronger electrical effect and flocculation performance compared with CS, resulting in more efficient dewatering performance. PDDA can reduce the pollutants of discharged residual water, while CS significantly promoted the increase of NH 4 +-N and NO 3 –-N in the residual water. The increase of NH 4 +-N in the residual water of CS was due to the release of dredged sludge, while the increase of NO 3 –-N was introduced by CS leaching. AHP showed that PDDA performed better in flocculation treatment of dredged sludge than other organic polymers. This work provides a method for optimization of flocculation treatment for dredged sludge dewaterability. [Display omitted] [ABSTRACT FROM AUTHOR]

We introduce a class of planar random source generating ring-shaped array profiles in the far field. The model for spatial correlation function of this new source is composed by the Fourier transform of the Laguerre-Gaussian array function with circular symmetry. The analytical expressions for the spectral density (average intensity) in free space and atmospheric turbulence are derived. The effect of the source parameters on the propagation properties are investigated in detail. Numerical results show that the source can produce a ring-shaped optical array profile consisting of dark-hollow-shaped or Gaussian-like-shaped beamlets at some distance, and then keep shape-invariant for long distances in free space. The number of rings, the position of beamlets, and other features can be conveniently controlled by changing the initial source parameters. In addition, increasing the relative separation distance of each beamlet or decreasing the radius of beamlets can reduce the turbulence-induced degradation. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric 0.75(Pb 1–3 x /2 La x )(Mg 1/3 Nb 2/3 )O 3 -0.25(Pb 1–3 x /2 La x )TiO 3 (La 3+ :PMN-PT x /75/25, where x =2.8, 3.0, 3.5, and 4.0 mol% of La 3+ ) transparent ceramics were fabricated by the combination of oxygen atmosphere pressureless sintering and hot-pressing sintering process. The optical transmittances of above four ceramics are higher than 60% at the wavelength of 500–900 nm. La 3+ :PMN-PT 3.0/75/25 exhibits the highest transparency around 70% at 900 nm which is very close to the theoretical transmittance 71%. Each of the four ceramics exhibits the pure perovskite phases. They show fully dense microstructures and their relative densities are higher than 99.8%. The ferroelectric and dielectric measurements indicate that these four ceramics exhibit relaxation characteristics. With increasing La 3+ content, (200) peak in XRD patterns shifts to higher angles and the average grain size increases, while the temperature Tε max corresponding to the maximum ε r , the remanent polarizations P r and coercive fields E c decrease gradually. [ABSTRACT FROM AUTHOR]

Highlights: [•] Living with parents during puberty reduces locomotor activity. [•] Post-weaning living with parents reduces contact interaction and sniffing. [•] Post-weaning living with parents increases the levels of parental care. [Copyright &y& Elsevier]

Abstract: Various hypotheses have been proposed to explain factors influencing male alloparental behavior in cooperatively breeding species. Mandarin voles (Microtus mandarinus) are ideal animal models to investigate these factors because they are highly social rodents and display biparental care and spontaneous parental care when exposed to foster pups. Here we test the idea that the sexual and paternal experience of males influences alloparental behavior toward novel pups, and that these experiences alter the expression of neuropeptide oxytocin (OT) and estrogen receptor alpha (ERα). Alloparental behavior and OT and ERα expression were compared between virgin males that had no prior sexual or reproductive experience, exposed males that with prior exposure to novel pups before the test, paired males that had been housed with a female, and new fathers having their first litter with a female. Our results show that prior exposure to novel pups and prior mating and paternal experience increased male alloparental behavior toward a novel pup. This experience also increased OT expression and affected the expression of ERα. This study reveals important initiation factors for male alloparental behavior and suggests a relationship between alloparental behavior and central OT expression in males. [ABSTRACT FROM AUTHOR]

Snails offer successful attachment and locomotion on horizontal and vertical surfaces, and have inspired extensive research to develop artificial adhesives. Here, we experimentally investigate the response mechanisms of snails to mechanical signals (pull-off force and crawling angle), then propose a way to design a bioinspired sucker, and theoretically analysis its application in vacuum suction. The experimental results indicate that the pull-off force is 7 N, about 22 times of its weight, and relatively invariant across the angles of the substrate. The flexible body increases work consumption by stretching and deformation during pulling, and a cavity with negative pressure differential can exist at the interface to help resist the pulling. We extract the flexible body and formation of a negative pressure cavity at the contact interface as two key elements of the bioinspired sucker, and the analysis shows that it can be adaptable to an extend range of products compared with conventional vacuum suction, which illustrates the potential for industrial or robotic manipulation. [ABSTRACT FROM AUTHOR]

Mesh denoising is a fundamental yet open problem in geometry processing. The main challenge is to remove noise while recovering the shape of the underlying surface as accurately as possible. In this paper, we propose a novel joint bilateral filter on the face normal field. The key is to estimate a reliable guidance normal field by constructing a shape-aware consistent patch for accurately describing the local shape of each face. To this end, we first select a candidate patch for each face by using a newly defined consistent metric considering both patch flatness and face-to-patch orientation similarity. Then, spectral analysis is used in combination with ℓ 0 minimization to refine the candidate patches in a shape-aware manner. The refined patches do not contain any features, and therefore they can accurately describe the local shape of the underlying surface. After smoothing the face normal field, vertex positions are reconstructed to match the filtered face normals. Our mesh denoising method is theoretically rooted and practical for dealing with the meshes containing corners with low sampling rates, multi-scale features, or narrow structure regions. Extensive experimental results demonstrate that our method can significantly improve the feature preserving capability of joint normal filter and outperforms state-of-the-art methods visually and quantitatively. [Display omitted] • A simple yet effective consistency metric is designed to select candidate patches. • A spectral partitioning method is introduced to produce shape-aware patches. • A variety of experiments to show that our method outperforms the state-of-the-arts. [ABSTRACT FROM AUTHOR]

Dredged sediment contains various contaminants that are released during the process of dewatering and subsequent utilization. In this study, two organic polymers—chitosan (CS) and cationic polyacrylamide (CPAM) both in samples of varying molecular weights (MWs)—were used as flocculants to improve dewatering and rheological behaviors of dredged sediment, and floc properties were characterized to unravel the mechanisms of flocculation treatment. Moreover, pollutant transfer and release in the flocculation-dewatering process was investigated. Compared to CPAM, CS had better performance in dredged sediment dewatering, and more compact flocs were produced after treatment. The flocculated sediment belonged to the type of yield dilatant fluid and showed good shear resistance. Three-dimensional excitation–emission matrix spectroscopy and PARAFAC showed that protein-like substances were removed after treatment. The MW of CS had insignificant effects on flocculation performance, whereas CPAM removal efficiency for protein-like substances was increased at higher MWs, which may be related to the adsorption bridging effect of CPAM polymer chains. There were significant correlations between the dewatering performance of sediments, MW distribution of organics and rheological properties. CS and CPAM treatments caused the transformation of Fe/Al-P into Ca P, which could reduce phosphorus release and its ecological risk. The flocculants contributed to the formation of carbonate-bound forms of As, Cr, Pb, and Ni. Ecological risk assessment results of the geo-accumulation index showed that medium- and low-MW CS reduced risk of sediment contamination, whereas CPAM and high-MW CS increased the ecological risk. CS had a greater effect on the release of VOCs than CPAM, with an increased release of total VOCs at higher flocculant MWs. The study was helpful to understand the dewatering mechanism of dredged sediment and provided a new strategy for pollution release management in sediment dewatering. Unlabelled Image • CS performed better in improving dredged sediment dewaterability than CPAM. • The floc produced by CS treatment was more compact than that flocculated with CPAM. • Sediment dewatering efficiency was related to protein-like substances removal. • Flocculation conditioning affected the form and transferring of pollutants in sediment. • Pollutant release and transferring behavior in flocculation conditioning was related to MW of polymers. [ABSTRACT FROM AUTHOR]

Isoliquiritigenin (ISL) is an emerging natural flavonoid found in the roots of licorice, exhibits antioxidant, anti-cancer, anti-inflammatory, anti-allergic, cardioprotective, hepatoprotective and neuroprotective properties. However, the effect of ISL in embryonic development is yet to be elucidated, and the mechanisms underlying its target-organ toxicity and harmful side effects are still unclear. In the present study, we employed zebrafish embryos to study the developmental toxicity effect of ISL and its underlying mechanisms. Zebrafish embryos upon treatment with either vehicle control (0.1% DMSO) or ISL solutions for 4–96 h post fertilization (hpf) showed that ISL exposure instigated severe developmental toxicity in heart, liver, and nervous system. Mortality and morphological abnormalities were also observed. High concentrations of ISL exposure resulted in abnormal phenotypes and embryonic malformations including pericardial edema, swim bladder defects, yolk retention, curved body shape and shortening of body length. Moreover, ISL exposure led to significant loss of dopaminergic neurons accompanied by reduced locomotor behaviour. Apoptotic cells were predominantly located in the heart area of 96 hpf embryo. Additionally, ISL significantly increased the levels of reactive oxygen species, lipid peroxidation content and decreased antioxidant enzyme activities. The expressions pattern of apoptosis-related genes Bad , Cyto c , Caspase-9 , Caspase-3 and Bax/Bcl-2 indicated that the oxidative stress–induced apoptosis triggered by ISL suggest involvement of Nrf2-HO1/JNK-ERK/mitochondrion pathways. In conclusion, here we provide first evidence that demonstrate ISL-induced dose-dependent developmental toxicity in zebrafish embryos. Furthermore, gene expression patterns in the embryos correlate the above and reveal potential genetic mechanisms of developmental toxicity. • ISL triggered developmental toxicity in zebrafish, caused death and malformations. • ISL exposure instigated developmental toxicity in heart, liver, and nervous system. • ISL triggered apoptosis in zebrafish via Nrf2-HO1/JNK-ERK/mitochondrion pathway. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol A (BPA) is a widespread endocrine disrupting chemical that influences adult physiology and behavior after perinatal exposure. However, it is not clear if pubertal exposure to BPA exerts hormone dependent effects on behaviors. Using C57BL/6J mice, we sought to determine how pubertal exposure to BPA affects locomotion, exploration, anxiety and sociability in adulthood. Compared to controls, pubertal exposure to BPA or E2 (17β-estradiol) significantly altered female exploratory and anxiety behavior. Moreover, BPA and E2-treated female mice displayed increased levels of affiliation to female stimulus mice and decreased levels of affiliation to male stimulus mice; while our control males showed affiliation preference to female stimulus. These results indicate that pubertal exposure to BPA or E2 may masculinize female social and emotional behavior. [Copyright &y& Elsevier]

The Asian honeybee ( Apis cerana ) is an important indigenous species that play an indispensable role in the ecological balance and biological diversity. Few studies have been conducted to characterize the simple sequence repeats (SSRs) derived from A . cerana , so, in this study, a genome-wide screening for SSRs were firstly performed in the genome of A . cerana by comparison with that in west honeybee ( Apis mellifera ). There were 20,9991 SSRs distributed throughout the genome of A . cerana (Korea strain) and di-nucleotides were the most frequent SSR type. Both total number and density of SSRs in A . cerana genome were smaller than that in A . mellifera genome. Through comparing length discrepancy of SSRs loci among several isolates based on sequence alignment, 218 potential polymorphic SSRs primers derived from A . cerana were presented. Five among these SSR markers were evaluated for amplification in twenty-eight colonies of Apis cerana cerana (Chinese honeybee), which showed highly polymorphic, with the value of Polymorphism information content (PIC) ranging from 0.47 to 0.61. All these results will contribute to further develop more effective SSRs markers derived from A . cerana , which can be used to study genetic structure and population polymorphism of Asian honeybee. [ABSTRACT FROM AUTHOR]