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Five new coordination polymers, namely [Ln(L)(NO3)2] n (Ln = La (1), Pr (2) and Sm (3)), [Eu(L)(NO3)2·1.5H2O] n (4) and [Tb(L)(OAc)2(H2O)·3H2O] n (5) (HOAc = CH3COOH), were synthesised by reaction of lanthanide nitrates with 1,3-bis(4-carboxybenzyl)benzimidazolium chloride (H2L+Cl−) under solvothermal conditions. All the coordination polymers were characterised by powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, elemental analysis and single crystal X-ray diffraction. Complexes 1 – 5 exhibit two different 2-D structures due to the variation in reaction temperature. Complexes 1 – 4 are isostructural and crystallised in the monoclinic system, C 2/ c space group, showing a two-dimensional layer with Ln chains linked by L− ligands. Complex 5 crystallised in the P 21/ n space group, featuring a 2-D layer different from 1 – 4 with Tb dimers linked by L− ligands through carboxylates. Further, the luminescence properties of complexes 3 – 5 were investigated. In addition, the fluorescence lifetime and quantum efficiency of complex 4 were measured. Five two-dimensional complexes were obtained and the structures of 1 – 4 differ from that of 5 owing to the distinct coordination modes of the ligand H2L+Cl− at specific reaction temperatures. Further, the luminescence properties of complexes 3 – 5 were investigated. Additionally, the fluorescence lifetime of complex 4 was tested. (Image credit: Li-Xin You.) [ABSTRACT FROM AUTHOR]

BACKGROUND Polymetallic nodules are predominant in deep sea sedimentary mineral resources due to the enrichment of many critical metals. Polymetallic nodules are loose and porous, which is the critical material feature that contributes the adsorption of trace metals from seawater and pore water and then enrichment and mineralization. Therefore, specific surface area (SSA) is one of the key factors for studying the ore-forming process of polymetallic nodules. At present, the methods for SSA determination are well-developed. However, they are less applied in the analysis of the specific surface of polymetallic nodules, and the pretreatment conditions are not constant according to various research targets. OBJECTIVES In order to explore the pretreatment conditions for the BET SSA analysis of polymetallic nodules, and provide necessary parameters for the study of the enrichment of trace metals in polymetallic nodules. METHODS Polymetallic nodules from the Atlantic, Indian, and Pacific oceans were collected. The pretreatment conditions including temperature, duration, and particle size for SSA analysis of polymetallic nodules were studies by applying temperature programming, heating accumulation, and particle size comparing methods. RESULTS The results showed that the analysis values of SSA reached plateau when the heating temperature ranged from 210℃to 350℃. The analysis values of SSA remained constant after heating for 3 hours by a step of 1 hour at 210℃. The SSA values of samples with a size of several millimeters were 1.027-28.535m2/g higher compared with those of the same samples crushed into microns. CONCLUSIONS Reliable SSA values can be obtained when the polymetallic nodules with sizes of several millimeters are heated in a vacuum system for 3 hours at 210℃, which is the pretreatment condition for analyzing SSA of mineralization-related polymetallic nodules.

Small vertical-axis wind turbines are a promising solution for affordable and clean energy, but their noise emissions present a challenge to public acceptance. Numerous blade designs have been aimed at reducing noise but often come with a decrease in wind turbine aerodynamic efficiency. In this study, the acoustic power and torque of a 5 kW vertical-axis wind turbine (VAWT) were simulated by using different mesh sizes and turbulence models. The simulated torque and noise of the turbine have significant sensitivity to the mesh size, so suitable mesh sizes were determined for the near-wall and rotating regions that can be used as a design reference for future turbines with similar operating conditions. The selection of the turbulence model was found to affect the predicted torque by about 10 % and the predicted tip noise by about 2 dB. The selected mesh size and turbulence model were then applied to simulating the effectiveness of three common noise mitigation techniques: a mask, deflector, and wall roughness. The results showed that deflectors are suitable for noise reduction of small VAWTs. This paper provides valuable information on simulating noise propagation from small VAWTs and the optimal noise reduction techniques. [ABSTRACT FROM AUTHOR]

An herbal prescription is usually composed of several herbal medicines. The complex and diverse components bring great challenges to its bioactivity study. To comprehensively analyze the bioactivity of an herbal prescription, a new strategy based on peak‐by‐peak cutting and knock‐out chromatography was proposed. In this strategy, active compounds were screened out via peak‐by‐peak cutting from an herbal extract, and the influence of a compound on the overall activity of the herbal extract was evaluated by knock‐out chromatography. Qiliqiangxin capsule is an herbal prescription composed of 11 herbal medicines for the treatment of chronic heart failure. A total of 71 peaks were collected through peak‐by‐peak cutting, and each peak was identified by a high‐resolution mass spectrum. The bioassay against 1,1‐diphenyl‐2‐picrylhydrazyl showed that two types of compounds namely salvianolic acids and caffeoylquinic acids were potent scavengers. Knock‐out chromatography suggested that the removal of one single compound had no obvious influence on the overall activity of the Qiliqiangxin capsule. After all the main peaks in the Qiliqiangxin capsule were knocked out, the remaining part still exhibited a potent activity, indicating high activity stability of the Qiliqiangxin capsule. The proposed strategy is helpful for the comprehensive analysis of the bioactivity of other herbal prescriptions. [ABSTRACT FROM AUTHOR]

One of the important criteria of the emergency planning (EP) exemption for nuclear power plant (NPP) decommissioning is a minimum of 10 h available before any spent nuclear fuel (SNF) cladding temperature reaches 900°C after a complete loss of the spent fuel pool (SFP) water inventory with no heat loss (adiabatic). This study used the computational fluid dynamics (CFD) code to analyze the cladding heatup time of the SFP for a boiling water reactor. First, the developed CFD local model of the SFP was compared with the U.S. Nuclear Regulatory Commission's (NRC's) report on SFP heatup calculations, NSIR-2015-001. The CFD results were similar to the theoretical calculations and MELCOR results for cases with and without racks. The results also indicated that racks can significantly delay the heatup time. This study also performed sensitivity studies to identify the effects of fuel burnup, hottest assembly, and fuel loading configurations. After validation of the CFD local model against MELCOR, a whole-pool CFD model of the Chinshan SFP was developed and successfully applied to analysis for the EP exemption of the Chinshan NPP. The results predicted using the whole-pool CFD model of the Chinshan SFP agreed well with the MELCOR results. Additionally, the required 900°C heatup times were calculated based on the actual decay heat of each cycle and fuel loading at the Chinshan SFP. The required 900°C heatup times were 19.1, 54, and 64.6 h for the Chinshan SFP at 1, 5, and 10 years after shutdown, respectively. The actual fuel loading and decay heat of the Chinshan SFP met the requirements for the EP exemption after 1 year of shutdown. The main purpose of this study is to demonstrate that the CFD code can be used as a tool to calculate SFP fuel assembly heatup times for the EP exemption. The advantage of using the CFD code instead of MELCOR is that the whole-pool SFP model can be developed based on the actual decay heat of each cycle and fuel loading and to determine more realistic fuel assembly heatup time for the EP exemption. [ABSTRACT FROM AUTHOR]

A selective recovery process for cobalt from the cathode materials of Li-ion batteries is demonstrated in this report. First, acid leaching was applied to dissolve the metals from the lithium-metal oxides. It was found out that with the assistance of probe type ultrasonication, manganese could be simultaneously separated by precipitation. This phenomenon would reduce the difficulty for later separation. Next, water-in-oil microemulsion extraction was applied for direct extraction of cobalt from the other metals. The cobalt extraction yield was 98% and purity was 96%. Moreover, the microemulsion system could be reused for 100 times without losing its extraction ability. [ABSTRACT FROM AUTHOR]

In this paper, an inverse method to identify the mechanical parameters of fiber metal laminates is proposed on the basis of the measured and calculated frequency response functions. The classical laminates theory, orthogonal polynomial method, and energy method are employed to characterize the theoretical modal of a fiber metal-laminated thin plate under pulse excitation. And, an iterative solution on the basis of frequency response functions and least square method is proposed to identify the mechanical parameters of fiber metal laminates, which conclude the elastic modulus, Poisson's ratios, and loss factors. As an example to demonstrate the feasibility of the developed inverse method, the experimental test of a TA2/TC 300 fiber metal-laminated thin plate is implemented to identify the mechanical parameters. Moreover, the influences of approximation points and calculation step sizes on the identification accuracy and efficiency are discussed. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Recently, novel approaches for the delivery of therapeutic antibodies have attracted much attention, especially sustained release formulations. However, sustained release formulations capable of carrying a high antibody load remain a challenge for practical use. In this study, a novel injectable hydrogel composed of maleimide-modified γ-polyglutamic acid (γ-PGA-MA) and thiol end-functionalized 4-arm poly(ethylene glycol) (4-arm PEG-SH) was developed for the subcutaneous delivery of trastuzumab. γ-PGA-MA and 4-arm PEG-SH formed a hydrogel through thiol-maleimide reactions, which had shear-thinning properties and reversible rheological behaviors. Moreover, a high content of trastuzumab (>100 mg/mL) could be loaded into this hydrogel, and trastuzumab demonstrated a sustained release over several weeks through electrostatic attraction. In addition, trastuzumab released from the hydrogel had adequate stability in terms of its structural integrity, binding bioactivity, and antiproliferative effect on BT-474 cells. Pharmacokinetic studies demonstrated that trastuzumab-loaded hydrogel (Her-hydrogel-10, composed of 1.5% γ-PGA-MA, 1.5% 4-arm PEG-SH, and 10 mg/mL trastuzumab) and trastuzumab/Zn-loaded hydrogel (Her/Zn-hydrogel-10, composed of 1.5% γ-PGA-MA, 1.5% 4-arm PEG-SH, 5 mM ZnCl 2 , and 10 mg/mL trastuzumab) could lower the maximum plasma concentration (C max) than the trastuzumab solution. Furthermore, Her/Zn-hydrogel-10 was better able to release trastuzumab in a controlled manner, which was ascribed to electrostatic attraction and formation of trastuzumab/Zn nanocomplexes. In a BT-474 xenograft tumor model, Her-hydrogel-10 had a similar tumor growth-inhibitory effect as that of the trastuzumab solution. By contrast, Her/Zn-hydrogel-10 exhibited a superior tumor growth-inhibitory capability due to the functionality of Zn. This study demonstrated that this hydrogel has potential as a carrier for the local and systemic delivery of proteins and antibodies. Statement of Significance Recently, novel sustained-release formulations of therapeutic antibodies have attracted much attention. However, these formulations should be able to carry a high antibody load owing to the required high dose, and these formulations remain a challenge for practical use. In this study, a novel injectable chemically cross-linked hydrogel was developed for the subcutaneous delivery of trastuzumab. This novel hydrogel possessed ideal characteristics of loading high content of trastuzumab (>100 mg/mL), sustained release of trastuzumab over several weeks, and maintaining adequate stability of trastuzumab. In vivo studies demonstrated that a trastuzumab-loaded hydrogel possessed the ability of controlled release of trastuzumab and maintained antitumor efficacy same as that of trastuzumab. These results implied that a γ-PGA-MA and 4-arm PEG-SH-based hydrogel has great potential in serving as a carrier for the local or systemic delivery of therapeutic proteins or antibodies. [ABSTRACT FROM AUTHOR]

Gelsolin (GSN) protein, expressed in circulating monocytes, was previously reported to be associated with osteoporosis in both Chinese and Caucasian women. This study aims to test if plasma GSN protein level is associated with hip bone mineral density (BMD) in Chinese population. Based on two study Groups containing 6,308 old Chinese, we adopted extreme sampling scheme and selected 3 independent samples (Subgroups 1–3) for discovery, replication, and validation purposes. We tested plasma GSN concentration, and analyzed whether plasma GSN level differs between subjects with extremely low vs. high hip BMD. In Group 1 (N = 1,860), the plasma GSN level increased in the female with low BMD, which was discovered in the Subgroup 1 (N = 42, p = 0.093) and replicated in the Subgroup 2 (N = 39, p = 0.095). With more extreme sampling for the Subgroup 3 from the Group 2 (N = 4,448), the difference of plasma GSN level in the female with low BMD vs. high BMD is more significant (N = 45, p = 0.037). After the subjects were pooled from Subgroups 2 and 3, the difference in plasma GSN between low and high BMD subjects became even more significant (p = 0.016). The plasma GSN level was negatively correlated with total hip BMD (r = -0.26, p = 0.033). We concluded that plasma GSN was associated with hip BMD in Chinese postmenopausal women and plasma GSN might be a potential risk biomarker for osteoporosis. [ABSTRACT FROM AUTHOR]

Low bone mineral density (BMD) is a risk factor of osteoporotic fracture (OF). Peripheral blood monocytes (PBM) can differentiate into osteoclasts to resorb bone. It was known that PBM-expressed Anxa2 protein is associated with BMD, and extracellular Anxa2 protein promotes osteoclastogenesis. This study aimed to test 1) whether Anxa2 protein level in PBM differs significantly between subjects with OF and without fracture history (NF); 2) whether Anxa2 level in plasma is associated with BMD; 3) how Anxa2 protein at various concentrations would affect osteoblastic activity in vitro. All the study subjects were Chinese Han elderly. Firstly, Anxa2 protein in PBM was identified and quantitated by LC-MS/MS and compared between 45 OF cases and 42 healthy controls. Secondly, plasma Anxa2 protein level was quantitated by ELISA and compared between unrelated subjects with extremely low vs. high hip BMD (0.63±0.10 vs. 1.05±0.10 g/cm2, n = 75). Furthermore, in vitro functional assay was utilized to test the effects of extracellular Anxa2 protein on osteoblastic growth. We found that Anxa2 protein expression in PBM was significantly up-regulated in OF vs. NF subjects (fold change [FC)] = 1.16, P<0.05). Plasma Anxa2 protein concentration (range: 31.69–227.35ng/ml) was significantly elevated in low vs. high BMD subjects (84.85 vs. 66.15ng/ml, FC = 1.28, P<0.05). Cellular dynamical monitoring demonstrated that the general shape of dose-response relationship is the inverse U-shaped curve. Specifically, lower dose of Anxa2 protein may promote osteoblast growth and the optimal concentration for osteoblastic growth was around 50ng/ml, but even higher concentration could attenuate hFOB1.19 osteoprogenitor cell growth. We concluded that Anxa2 protein could attenuate osteoblast growth and be associated with hip BMD and OF in Chinese elderly. [ABSTRACT FROM AUTHOR]

Geniposide (GE) is the extraction and purification of iridoid glycosides from the Gardenia jasminoides Ellis, which is a promising anti-inflammatory drug, but its mechanism of actions on rheumatoid arthritis (RA) has not been clarified. This study investigated the molecular mechanism behind GE reduced the high permeability of fibroblast-like synoviocytes (FLSs) derived from SD rats with adjuvant arthritis (AA), with the aims of observing the action of GE in AA rats and exploring new therapeutic strategies for RA treatment. The CCK-8 method was used to detect FLSs proliferation. The pro-inflammatory cytokines levels and anti-inflammatory cytokines levels in FLSs were determined by ELISA kits. FLSs permeability assay was performed on Transwell. Immunofluorescence was used to assay the arrangement and morphology of F-actin. The expression of the key molecules related to FLSs permeability (RhoA, p-p38MAPK, NF-κB p-p65 and F-actin) was detected by western blotting. After treatment with lipopolysaccharide (LPS), the proliferation and the permeability of the cells increased significantly (all P < 0.05). The expression of RhoA, p-p38MAPK, NF-κB p-p65 and F-actin in FLSs was higher compared with the control group, and F-actin was redistributed, with the formation of additional stress fibers. But, these conditions were moderated after treatment with GE. We demonstrated that the treatment of different concentrations of GE (25, 50, and 100 mg/mL) had a significant inhibitory effect on the proliferation and permeability of FLSs in vitro. Furthermore, the levels of interleukin (IL)-1β and IL-17 secreted by FLSs were decreased in different doses of GE groups, and the levels of anti-inflammatory cytokines (IL-4, TGF-β1) were increased. Under treatment with GE, low expression of RhoA downregulated expression of p-p38MAPK, NF-κB p-p65, and F-actin while compared with control group, and restored the hyperpermeability of FLSs due to LPS treatment. Taken together, GE might play its anti-inflammatory and immunoregulatory effects via regulating the relative equilibrium of pro-inflammatory cytokines and anti-inflammatory cytokines. GE attenuated the hyperpermeability of FLSs. The down-regulation of the conduction of RhoA/p38MAPK/NF-κB/F-actin signal may play a critical role in the mechanisms of GE on RA. GE could be an effective therapeutic agent for the treatment of RA. [ABSTRACT FROM AUTHOR]