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Abstract: To investigate the molecular mechanisms of lipid-lowering drug, Rhizoma Curcumae Longae, we treated the mouse macrophages with curcumin, which was purified from the ethanol extraction of Rhizoma Curcumae Longae. The LDL receptors expressed in the macrophages were determined by ELISA, FLISA and assay of LDL uptake. Here for the first time, we found that curcumin obviously up-regulated the expression of LDL receptor in mouse macrophages, and the dose–effect relationship was demonstrated. [Copyright &y& Elsevier]

Abstract: During a 4-week period in late spring 1998 an extensive Prorocentrum minimum (Pavillard) Schiller bloom developed in several tributaries of the Chesapeake Bay. Experiments were carried out in one of these tributaries using 13C and 15N isotopic techniques to characterize C and N uptake as a function of irradiance during the course of this bloom. Uptake rates of N substrates (NO3-, NH4+, urea, and an amino acid mixture) and C substrates (bicarbonate and urea) were measured. For each N substrate, short-term uptake rates (0.5h) were not substantially different over the irradiance range measured, suggesting that N uptake of this dinoflagellate was not strongly light-dependent over this time scale. Dark uptake rates of all N substrates ranged between 35 and 113% of light uptake rates. Over the duration of the P. minimum bloom, however, total ambient N uptake rates increased with increasing natural irradiance. Uptake of bicarbonate showed typical light-dependent photosynthetic characteristics and the measured photosynthetic parameters suggested that at least on the short time scale (0.5h), P. minimum cells were adapted to high light. Rates of C uptake from the substrate urea were minimal, <1% of total C uptake from photosynthesis, but doubled over the course of the bloom, and like N uptake, were not strongly light-dependent on the short time scale (0.5h). Significant N dark uptake by P. minimum was likely to have been important by providing N sources over the daily scale to sustain the bloom. [Copyright &y& Elsevier]

During the late spring and early summer of 1998, an extensive bloom of the dinoflagellate Prorocentrum minimum (>93% of phytoplankton cell density) developed in several tributaries of the Chesapeake Bay, USA. In January 1999, a bloom of mixed dinoflagellates (Heterocapsa rotundata, H. triquetra and P. minimum, with P. minimum forming 21% of total phytoplankton cells and 39% of the total biovolume) developed in the mesohaline Neuse Estuary, North Carolina, USA. During these blooms, experiments were carried out to characterize the nitrogen uptake kinetics of these assemblages with 15N isotopic techniques. Four nitrogenous substrates (NO3−, NH4+, urea, and a mixed amino acids substrate) were used to determine uptake rate and substrate preference. Rates of nitrogen uptake were also measured in P. minimum cultures grown on varying growth nitrogen substrates. The calculated kinetic parameters determined for the P. minimum-dominated field assemblages and the cultures indicated a preference for NH4+. NH4+ was also the primary nitrogen source supporting the blooms. In addition, a high affinity for urea was also found, and urea contributed significantly to the Neuse Estuary bloom. Furthermore, results showed that the regulation of uptake for each of the substrates was different: strong positive relationships between affinity and temperature were found for NH4+ and amino acids, while a negative response was found for NO3−, and very little response to temperature was noted for urea. These differences suggest that a diversity of nitrogen uptake mechanisms may aid the development and maintenance of P. minimum blooms. [Copyright &y& Elsevier]

• The ballistic tests of RSW specimens are performed on gas gun system with VISAR. • The shearing near notch tip and partial opening of RSW specimens are found. • The through-thickness fracture and interfacial fracture of RSW specimens are revealed. • The crack propagation of corona bond and pre-crack of RSW specimens is investigated. The ballistic tests of Q&P980 resistance-spot-welded (RSW) overlapping plates impacted at RSW joint by round-nosed bullet were performed using a single-stage gas gun system with a laser velocity interferometer system for any reflector (VISAR). The deformation and fracture mechanism of the RSW specimens were investigated by using the VISAR measured results, the metallographic cross-section observation and the scanning electron microscope (SEM) analysis of the recovered RSW specimens. The dynamic response of the RSW specimens was related to the reflection and refraction of the impact stress waves on the material interfaces and the free surfaces in the RSW specimens. The bulging, dishing, shearing near the notch tip and partial opening of the RSW specimens were discussed. With the range of loading speed and the joint configuration (overlap structure, nugget size, etc.) studied in this work, the plugging fracture should be a prevailing mode. The crack propagation of the corona bond and pre-crack of the RSW specimens under impact loading was found to affect the dynamic fracture process of the RSW specimens under bullet impact. [ABSTRACT FROM AUTHOR]

Abstract Nutrient bioextraction using Gracilaria lemaneiformis co-cultured with Crassostrea gigas in a eutrophic, intensive mariculture area was evaluated over 49 days in Yantian Bay, which is an enclosed bay within Sansha Bay, China. The amount of nitrogen removed by G. lemaneiformis was 4.07 ± 0.25 kg and 4.49 ± 0.57 kg per ton (FW) at depths of 0.4–0.8 m and 1.0–1.2 m, respectively. The ranges of ammonium-nitrogen (NH 4 -N), nitrite-nitrogen (NO 2 -N), nitrate-nitrogen (NO 3 -N), and inorganic phosphate (PO 4 -P) reduction efficiencies in the co-cultured area were 39.22–80.34%, 4.70–26.14%, 13.42–48.84%, and 25.33–41.36%, respectively. The total wet weight of harvested G. lemaneiformis was 5.44 and 3.92 times greater than the initial mass (500 g FW/m), with highest specific growth rates (SGR) of 4.67 ± 0.21%/d and 3.44 ± 0.18%/d at 0.4–0.8 m and 1.0–1.2 m, respectively. A total of 3.11 kg of nitrogen could be removed from the co-cultured area per ton of C. gigas harvested with a total length (TL) of 80 ± 12 mm. Based on the nitrogen balance in this co-cultured system, the largest proportion of nitrogen removal from the co-cultured system was the harvest production of G. lemaneiformis (25.44%), followed by C. gigas (8.27%). The quantity of nitrogen excreted and metabolized by C. gigas was 33.40 kg, which could be entirely assimilated by the G. lemaneiformis during the experimental period. Based on these results, at least 6.76 tons of G. lemaneiformis should be co-cultured per ton of C. gigas (77–80 mm TL) to remove the nitrogen produced by C. gigas in this mariculture area. The results of this study indicate that the co-culture G. lemaneiformis with C. gigas is an environmentally-friendly mariculture method which could effectively remove surplus nutrients and reduce the environmental impact of mariculture areas. Highlights • It is environmentally advantageous to co-culture Gracilaria lemaneiformis with Crassostrea gigas in an enclosed bay. • Nutrients flux of the co-cultured system was determined. • A field scale evaluation of G. lemaneiformis in the co-cultured system as a bioextraction strategy was given. [ABSTRACT FROM AUTHOR]

Defocus incorporated multiple segments (DIMS) spectacle lenses were reported to slow myopia progression significantly in a randomized controlled trial (RCT). The study evaluated their effectiveness in clinical settings. Retrospective study. Patient records involving use of DIMS and single-vision (SV) spectacle lenses were collected from subsidiary hospitals of Aier Eye Hospital Group. The spherical equivalent (SE), determined by subjective refraction, was adopted to assess the myopia progression. The strategy of propensity score matching (PSM) was applied to match the confounding baseline characteristics between the 2 groups. The effectiveness was calculated based on the difference of myopia progression of these 2 approaches. Change in SE. Three thousand six hundred thirty-nine patients with DIMS and 6838 patients with SV spectacles were included. The age of the patients was 6 to 16 years (mean ± standard deviation: 11.02 ± 2.53 years). The baseline SE was between 0.00 and –10.00 diopters (D) (mean ± standard deviation: –2.78 ± 1.74 D). After the PSM, data on 2240 pairs with 1-year follow-up and on 735 pairs with 2-year follow-up were obtained. Significantly slower progression was seen in the DIMS group at both the 1-year (DIMS, –0.50 ± 0.43 D; SV, –0.77 ± 0.58 D; P < 0.001) and 2-year (DIMS, –0.88 ± 0.62 D; SV, –1.23 ± 0.76 D; P < 0. 001) subdataset. In the 1-year subdataset, 40% and 19% showed myopia progression of no more than 0.25 D for the DIMS and SV groups, respectively (chi-square, 223.43; P < 0.001), whereas 9% and 22% showed myopia progression of more than 1.00 D for the DIMS and SV groups, respectively (chi-square, 163.38; P < 0.001). In the 2-year subdataset, 33% and 20% showed myopia progression of no more than 0.50 D for the DIMS and SV groups, respectively (chi-square, 31.15; P < 0.001), whereas 12% and 29% showed myopia progression of more than 1.50 D for the DIMS and SV groups (chi-square, 65.60; P < 0.001). Although the magnitude was lower than that reported in the previous RCT, this large-scale study with diversity of the data sources confirmed the effectiveness of DIMS spectacles to slow myopia progression in clinical practice. Proprietary or commercial disclosure may be found after the references. [ABSTRACT FROM AUTHOR]

The stability of prismatic columns subjected to internal axial loads is a common issue during engineering analysis and design. Because of the big difference between the effects of internal loads and end loads, the traditional effective length method is not applicable. Current codes do not provide design method for this issue and engineers require the ability to analysis and design this kind of columns efficiently. Using the concept of negative stiffness, a relationship between end loads and internal axial loads applied on sway-permitted prismatic columns is established so that the internal loads can be considered equivalent to end loads and the critical value can be obtained easily by Euler formula. A practical method to determine the second-order effect is also developed. Eigenvalue buckling and elastic nonlinear analyses are performed to examine the proposed method and the comparison results indicate it has high accuracy. [ABSTRACT FROM AUTHOR]

Abstract: Prorocentrum minimum (Pavillard) Schiller, a common, neritic, bloom-forming dinoflagellate, is the cause of harmful blooms in many estuarine and coastal environments. Among harmful algal bloom species, P. minimum is important for the following reasons: it is widely distributed geographically in temperate and subtropical waters; it is potentially harmful to humans via shellfish poisoning; it has detrimental effects at both the organismal and environmental levels; blooms appear to be undergoing a geographical expansion over the past several decades; and, a relationship appears to exist between blooms of this species and increasing coastal eutrophication. Although shellfish toxicity with associated human impacts has been attributed to P. minimum blooms from a variety of coastal environments (Japan; France; Norway; Netherlands; New York, USA), only clones isolated from the Mediterranean coast of France, and shellfish exposed to P. minimum blooms in this area, have been shown to contain a water soluble neurotoxic component which killed mice. Detrimental ecosystem effects associated with blooms range from fish and zoobenthic mortalities to shellfish aquaculture mortalities, attributable to both indirect biomass effects (e.g., low dissolved oxygen) and toxic effects. P. minimum blooms generally occur under conditions of high temperatures and incident irradiances and low to moderate salinities in coastal and estuarine environments often characterized as eutrophic, although they have been found under widely varying salinities and temperatures if other factors are conducive for growth. The physiological flexibility of P. minimum in response to changing environmental parameters (e.g., light, temperature, salinity) as well as its ability to utilize both inorganic and organic nitrogen, phosphorus, and carbon nutrient sources, suggest that increasing blooms of this species are a response to increasing coastal eutrophication. [Copyright &y& Elsevier]

The sandwich structure has superior properties. To explore the application of sandwich structures in steel plate shear walls, this study presents a sandwich steel plate shear wall with embedded corrugated plate (ECSSW). The proposed wall is composed of two flat plates and a corrugated plate embedded between them. The flat and corrugated plates are joined by connectors. To study the cyclic behavior of the ECSSW, a quasi-static test and a numerical simulation of two specimens were conducted. In addition, a parametric assessment was conducted on the ECSSW with different connector horizontal spacings and strengths. The results showed that the ECSSW provides satisfactory seismic performance, does not produce significant noise, and can effectively delay the occurrence and development of infill plate buckling. With a small-wavelength embedded corrugated plate, the ECSSW can increase the yield load and yield displacement. The ECSSW with a large-wavelength embedded corrugated plate can reduce stiffness degradation and increase ductility and energy dissipation. When the strength of the connector is low, its horizontal spacing has minimal effect on the cyclic behavior of the ECSSW. The strength of the connector significantly affects the out-of-plane deformation of the ECSSW. • Application of sandwich structures in realm of steel-plate shear walls was explored. • A sandwich steel plate shear wall with embedded corrugated plate was proposed. • Seismic performance of the proposed shear wall was studied. • The proposed shear wall has three ductile fuses, namely flat plate, embedded corrugated plate, and frame. • Strength of the connectors significantly affects the proposed shear wall out-of-plane deformation. [ABSTRACT FROM AUTHOR]

This study proposes a new interior diaphragm joint between wall-type reinforced concrete column with high-strength spiral stirrups and steel beams, and the quasi-static test was conducted to investigate the seismic performance of the new joint under cyclic lateral force. Finite element model (FEM) simulation was carried out using the software ABAQUS, and the correctness of the FEM was verified by the results of the test. Additionally, the effect of parameters including the strength of concrete, thickness of the beam flange, interior diaphragm, joint flange, and joint web on the seismic performances of the joint was analyzed. Based on the parametric analysis and existing codes, a shear capacity formula was determined with the consideration of the shear capacity of the joint web and flange, and concrete. The comparison between the calculated and FEM results indicates that this formula could be regarded as an accurate calculation method for the shear-bearing capacity of different joint types in engineering design. • A new type of joint connecting steel beams and wall-type RC columns with high-strength spiral stirrups was proposed. • The seismic performance of the connection was studied using quasi-static tests. • The two compressive diagonal struts mechanism was used in the shear capacity of the concrete. • The shear capacity of the joint core area was analyzed. • The simplified nonlinear model and boundary condition save time cost. [ABSTRACT FROM AUTHOR]

Abstract: A kinetic–frictional model, which treats the kinetic and frictional stresses in an additive manner, was incorporated into the two fluid model based on the kinetic theory of granular flow to simulate three dimensional flow behaviors of dense phase pneumatic conveying of pulverized coal in horizontal pipe. The kinetic stress was modeled by the kinetic theory of granular flow, while the friction stress is from the combination of the normal frictional stress model proposed by Johnson and Jackson [1987. Frictional–collisional constitutive relations for granular materials, with application to plane shearing. Journal of Fluid Mechanics 176, 67–93] and the modeled frictional shear viscosity model proposed by Syamlal et al. [1993. MFIX documentation and theory guide, DOE/METC94/1004, NTIS/DE94000087. Electronically available from http://www.mfix.org], which was modified to fit experimental data. For the solid concentration and gas phase Reynolds number was high, the gas phase and particle phase were all treated as turbulent flow. The experiment was carried out to validate the prediction results by three kinds of measurement methods. The predicted pressure gradients were in good agreement with experimental data. The predicted solid concentration distribution at cross section agreed well with electrical capacitance tomography (ECT) image, and the effects of superficial velocity on solid concentration distribution were discussed. The formation and motion process of slug flow was demonstrated, which is similar to the visualization photographs by high speed video camera. [Copyright &y& Elsevier]

• Traditional surveys do not efficiently sample forage fish in shallow estuaries. • Sonar imaging produces high-resolution, fine-scale forage fish distribution data. • Forage fish mostly aggregate in shallow water creeks. • We recommend sonar imaging be used to supplement traditional sampling approaches. Forage fish are economically and ecologically important to many coastal marine ecosystems, but most forage fish species are not targeted in species-specific abundance surveys. In the Chesapeake Bay, Atlantic menhaden (Brevoortia tyrannus), an important forage species for many upper-trophic level consumers, are sampled with beach seines and midwater trawls. There is evidence that these traditional fish sampling gears are insufficient for observing menhaden abundance and distribution, which may lead to biased and inaccurate indices of abundance. We suggest this is due to omitting or under-sampling shallow estuarine creeks and nearshore areas. We tested this hypothesis in the Patuxent River, Maryland and its surrounding shallow-water creeks, which are representative of many estuarine tributaries with varied bathymetry. Sonar imaging surveys were conducted using Adaptive Resolution Imaging Sonars (ARIS 1800 and 3000) and a generalized additive model was fit to the resulting data to model forage fish density. Results indicated that menhaden and other forage fish were present at significantly higher densities in shallow-water creeks than in deeper-water areas. Further, many forage fish were observed in creek habitats frequently omitted by both seines and trawls, suggesting that these survey designs may result in biased forage fish indices of abundance. Therefore, we recommend current forage fish surveys in the Chesapeake Bay, especially those with the intent of developing juvenile menhaden indices of abundance, be supplemented with hydroacoustic surveys in shallow waters to improve accuracy and reduce bias. [ABSTRACT FROM AUTHOR]

• An in-situ imaging system captured Noctiluca bloom in Dapeng Bay, P.R. China. • A logistic growth model was applied to simulate the growth and decay of Noctiluca. • We demonstrated an early warning framework using the in-situ observations and model. The frequency and intensity of harmful algal blooms (HABs) are likely to increase with climate change and increases in nutrients due to anthropogenic activities. To manage the environment and health threats to surrounding organisms, it is essential to improve our capability to provide early warning of harmful species. Using Noctiluca scintillans as example, a dinoflagellate that often blooms in Asia and whose presence is rapidly expanding worldwide, we demonstrate a potential way to predict N. scintillans blooms by deploying an in-situ plankton imaging system: PlanktonScope. PlanktonScope is a shadowgraph imaging system and capable of imaging organisms 40 µm – 5 cm. This system was deployed in Shenzhen Bay, China, recording images at 0.5 Hz in April 2016. Using the automated image processing procedure, we found that PlanktonScope recorded nearly a full cycle of a N. scintillans bloom. A simple resource-limited logistic population growth model was then applied to develop a predictive framework for the outburst of N. scintillans. Environmental changes could explain the observed dynamics of N. scintillans ; however, it was difficult to quantify the relationship between the dynamics of N. scintillans and environmental variables. Our study demonstrated that a camera system like PlanktonScope could be useful in developing an early warning system for N. scintillans blooms, which could be applicable to other HAB species for proactive management. [ABSTRACT FROM AUTHOR]