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Abstract: Although microporosity and surface area of natural organic matter (NOM) are crucial to mechanistic evaluation of the sorption process for nonpolar organic contaminants (NOCs), they have wrongly been estimated by the N2 adsorption technique. Nuclear magnetic resonance spectroscopy (13C NMR), and benzene, carbon dioxide, and nitrogen adsorption techniques were used to characterize structural and surface properties for different condensed NOM samples, which were related to the sorption behavior of phenanthrene (Phen). It was found that the revised Freundlich model by taking the chemical activity into account can well describe the isotherms for benzene and Phen. The benzene and Phen adsorption volumes for the coal samples are similar to or lower than the CO2-nanopore volumes. Adsorption volumes of both benzene and Phen are significantly related to the aliphatic carbon structure, and their correlation lines are nearly overlapped, suggesting that the nanopore filling for Phen and benzene on the investigated samples is the dominating mechanism, and also is not affected by water molecules. The entrapment of benzene and/or the pore deformation in the NOM nanopore are likely responsible for the observed hysteresis of benzene. The above results demonstrate that Phen and benzene adsorption on the condensed NOM is closely associated with the aliphatic carbon structure of the investigated samples. [Copyright &y& Elsevier]

Detection of viral nucleic acids by pattern recognition receptors initiates type I interferon (IFN) induction and innate antiviral response. The RIG-I-like receptors (RLRs), including RIG-I and MDA5, recognize cytoplasmic viral RNA in most cell types and are critically involved in innate antiviral response. RIG-I and MDA5 are structurally related and mediate similar signaling pathways. While the regulation of RIG-I activity has been extensively investigated, little is known about the regulatory mechanisms of MDA5 activity. Here we identified ribonucleoprotein PTB-binding 1 (RAVER1) as a specific MDA5-interacting protein. RAVER1 was associated with MDA5 upon viral infection. Overexpression of RAVER1 at low dosages enhanced MDA5- but not RIG-I-mediated activation of the IFN-β promoter, whereas knockdown of RAVER1 inhibited MDA5- but not RIG-I-mediated induction of downstream antiviral genes. Mechanistically, overexpression of RAVER1 enhanced the binding of MDA5 to its ligand poly(I:C), whereas knockdown of RAVER1 had opposite effect. Our findings suggest that RAVER1 specifically regulates MDA5 activity, revealing a mechanism of differential regulation of MDA5- and RIG-I-mediated innate antiviral response. [ABSTRACT FROM PUBLISHER]

Abstract: Three faults were involved in the rupture process of the May 12, 2008 Mw7.9 Wenchuan earthquake, representing a rarely documented case of multiple faults rupturing simultaneously. Distinct from the other two major NE-trending surface ruptures, the ~7km long Xiaoyudong surface rupture is oriented NW340° and shows thrust- and left‐slip faulting. In order to understand what role Xiaoyudong rupture played in the tectonic evolution of Longmenshan thrust system, we conducted a detailed investigation including geomorphic feature observation, coseismic displacement measurement, paleo-rupture event trenching, and fault kinematic estimation of the Xiaoyudong area. Our results not only document an in situ paleoearthquake occurring at 3.2–2.3ka BP, but also present the Xiaoyudong rupturing event as an oblique thrust with minor components of left lateral slip. We also found vertical and sinistral slip rates estimated as 1.1–1.5mm/yr and 0.5–0.7mm/yr, respectively. Finally, we suggest that the Xiaoyudong rupture is not a passive tear fault but an active participator of slip partitioning on multiple faults within the Longmenshan thrust system, and moreover, it gave strong response to both the 2008 and the penultimate earthquake while it kept silence with the antepenultimate event. [Copyright &y& Elsevier]

The article discusses the regulatory effect of E3 ubiquitin ligase MIB1 on (NF)-κB activation. It notes the impact of MIB1 deficiency in the IκBα level indicating the upregulation of the IκBα level in MIB1-deficient cells. Furthermore, the roles of MIB1 in tumor necrosis factor (TNF)α- or interleukin-1 (IL1)beta-induced gene transcription are explored.

Transcription factor IRF3-mediated type I interferon induction is essential for antiviral innate immunity. We identified the deSUMOylating enzyme Sentrin/SUMO-specific protease (SENP) 2 as a negative regulator of virus-triggered IFN-β induction. Overexpression of SENP2 caused IRF3 deSUMOylation, K48-linked ubiquitination, and degradation, whereas depletion of SENP2 had opposite effects. Both the SUMOylation and K48-linked ubiquitination of IRF3 occurred at lysines 70 and 87, and these processes are competitive. The level of virus-triggered IFN-β was markedly up-regulated and viral replication was reduced in SENP2-deficient cells comparing with wild-type controls. Our findings suggest that SENP2 regulates antiviral innate immunity by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation, and provide an example of cross-talk between the ubiquitin and SUMO pathways in innate immunity. [ABSTRACT FROM PUBLISHER]

Abstract: The endocrine-disrupting chemicals (EDCs) was investigated in 28 riverine sediments from the Pearl River system, China and analyzed by an ultrasonication extraction and GC–MS method. The concentrations of 4-tert-octylphenol (OP), 4-nonylphenol (NP), and bisphenol A (BPA) in the sediments were in the ranges of <2.0–210, 107–16198 and <1.7–430ng/g dw, respectively. The steroid estrogens estrone (E1) and 17β-estradiol (E2) in the sediments ranged from <1.3 to 10.9ng/gdw and from <0.9 to 2.6ng/gdw, respectively. The spatial distribution of these chemicals was related to the discharge of domestic and industrial wastewater along the rivers. The positive correlation between EDCs and total organic carbon indicates that sedimentary organic carbon is an important factor in controlling the distributions of EDCs. Compared with other previous studies, the ZR and DR rivers from the PRD were heavily contaminated by APs and BPA. [Copyright &y& Elsevier]

IFN-stimulated gene 56 (1SG56) is one of the first identified proteins induced by viruses and type I IFNs. In this study, we identified 1SG56 as a virus-induced protein associated with MITA, an adapter protein involved in virus-triggered induction of type I IFNs. Over-expression of 1SG56 inhibited Sendai virus-triggered activation of IRF3, NF-κB, and the IFN-β promoter, whereas knockdown of 1SG56 had opposite effects. Consistently, overexpression of 1SG56 re- versed. cytoplasmic poly(I:C)-induced inhibition of vesicular stomatitis virus (VSV) replication, whereas knockdown of ISG56 inhibited VSV replication. Competitive coimmunoprecipitation experiments indicated that 1SG56 disrupted the interactions between MITA and VISA or TBK1, two components in the virus-triggered IFN signaling pathways. These results suggest that 1SG56 is a mediator of negative-feedback regulation of virus-triggered induction of type I IFNs and cellular antiviral responses. [ABSTRACT FROM AUTHOR]

The material sensitivity coefficient of Fatemi-Socie model (FS model) is proved to be not a constant for different materials and the effect of the shear stress on fatigue life is not considered. In this condition, a new multiaxial fatigue prediction model considering the shear stress and material sensitivity is established based on the critical plane method in this paper. Firstly, the material plane with the maximum shear strain amplitude is defined as the critical plane and a calculating method to determine the location of critical plane is presented. Secondly, a calculating method of material sensitivity coefficient k ' is proposed considering the effects of both the stress and strain on the critical plane by investigating the relationship between material sensitivity coefficient and the multiaxial fatigue life. Besides, the effect of the normal strain amplitude on the critical plane is considered because it has a certain impact on multiaxial fatigue life. Finally, four materials, including 45 steel, 316 L stainless steel, GH4169 alloy, and 7075-T651 aluminum alloy, are adopted to verify the feasibility and correctness of the proposed model under the proportional and non-proportional loading condition by comparing the equivalent strain model, the maximum shear strain model, the SWT model, KBM model, and FS model with the experimental result. The comparison results show that the prediction life of the proposed model is only second to the KBM model under multiaxial proportional loadings, but the prediction capability is superior to the other five models and the majority of the prediction results are within the scatter band with factor 3 under non-proportional loadings. • The effects of the shear stress and normal stress on multiaxial fatigue life are discussed. • A new calculating method of the material sensitivity coefficient is established. • The relationship between normal strain amplitude and the fatigue life is studied. • A new multiaxial fatigue life prediction model is established. [ABSTRACT FROM AUTHOR]

Lijiang-Daju fault, the seismogenic fault of the 1996 Lijiang M=7.0 earthquake, can be divided into Lijiang-Yuhu segment in the south and Yuhu-Daju segment in the north. The two segments show clear difference in geological tectonics, but have the similar dynamic features. Both normal dip-slip and sinistral strike-slip coexist on the fault plane. This kind of movement started at the beginning of the Quaternary (2.4–2.5 Ma B.P.). As to the tectonic types, the detachment fault with low angle was developed in the Early Pleistocene and the normal fault with high angle only after the Mid-Pleistocene (0.8 Ma B.P.). Based on the horizontal displacements of gullies and the vertical variance of planation surfaces cross the Lijiang-Daju fault at east piedmont of Yulong-Haba range, the average horizontal and vertical slip rates are calculated. They are 0.84 mm/a and 0.70 mm/a since the Quaternary and 1.56 mm/a and 1.69 mm/a since the Mid-Pleistocene. The movements of the nearly N-S-trending Lijiang-Daju fault are controlled not only by the regional stress field, but also by the variant movement between the Yulong-Haba range and Lijiang basin. The two kinds of dynamic processes form the characteristics of seismotectonic environment of occurring the 1996 Lijiang earthquake. [ABSTRACT FROM AUTHOR]

Geomorphic study on Wujiahe segment of Serteng piedmont fault, Inner Mongolia is made. Through analysis of the available data in combination with the results of predecessors’ studies it can be obtained that average vertical displacement rate is 0.48–0.75 mm/a along the Wujiahe segment since the late Pleistocene (14.450–22.340 ka BP) and 0.56–0.88 mm/a since the early-middle Holocene (5.570–8.830 ka BP). Analyzing paleoseismic phenomena revealed in the excavated 5 trenches in combination with the results of predecessors’ studies of paleoearthquakes on the fault, we determine five paleoseismic events on the Wujiahe segment of Serteng piedmont fault since 27.0 ka BP and the recurrence interval to be about 4.300–4.400 ka. A cluster of paleoearthquakes occurred probably during 8.000–9.000 ka BP and two paleoseismic events in 10.000–20.000 ka BP may be missed. A comparison between height of fault scarps and sum of displacement caused by paleoseismic events revealed in trenches, and recurrence interval of paleoseismic events obtained from average displacement rate along the fault and the dislocation by one event suggest that three paleoseismic events are absent in Alagaitu trench. Two paleoseismic events may be absent on the whole active fault segment. [ABSTRACT FROM AUTHOR]

By means of an iteration method and taking into account the broadening of the infrared pumping laser, the spectrum of a miniature, optically pumped, superradiant NH3 submillimeter-wave(SMMW) gas laser pumped by CO2-10R(8) has been calculated and studied by solving density matrix equations. Experimentally, the interferogram of miniature SMMW laser pumped by a TEA-CO2 laser with 10R(8) line is measured. This is the first time that the theoretical spectrum has been in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Deterministic, probabilistic and composite-grading methods are used to get the possible locations of strong earthquakes in the future in Norwest Beijing and its vicinity based on the quantitative data and their accuracy about active tectonics in the research area and by ordering, some questions in the results are also discussed. It shows that the most dangerous fault segments for strong earthquakes in the future include: segments B and A of the southern boundary fault of the Yangyuan basin, the southern boundary fault of the Xuanhua basin, the east segment of the southern Huai’an fault and the east segment of the northern Yanggao-Tianzhen fault. The most dangerous area is Yangyuan-Shenjing basin, the second one is Tianzhen-Huai’an-Xuanhua basin and the third dangerous areas are Wanquan-Zhangjiakou and northeast of Yuxian to southwest of Fanshan. [ABSTRACT FROM AUTHOR]

Sorption and desorption of 1,4-dichlorobenzene (DCB) on peat (> 92% organic matter) display large-scale hysteresis and nonlinearity. The magnitude of desorption hysteresis decreases in the order: untreated Pahokee peat (P)> acid treated peat (FP)> humin (TP). The desorption percentages are lower than 28% of the sorbed 1, 4-DCB after desorbing for 6 days. The sorption and desorption isotherms are well fitted to Freundlich equation, whose parameter 1/n ranges from 0.055 to 0.527. Moreover, the parameter 1/n of the desorption isotherm is significantly lower than that of the sorption isotherm, but the parameter logK increases on contrary to 1/n. The desorption isotherms are very well fitted to Langmuir equation, whose Qm decreases in the order: TP> FP> P. The apparent partition coefficients (KP) increase with increasing sorption time or decreasing aqueous equilibrium concentration of DCB. AndKP of P is significantly higher than that of FP or TP. [ABSTRACT FROM AUTHOR]

To investigate the effects of notched root stress gradient and geometric size parameters on the fatigue performance of engineering components, a new multiaxial fatigue life prediction model is established. First, based on the energy‐critical plane method, the location of the dangerous plane is determined with the help of finite element (FE) analysis. Second, the sixth‐order multinomial stress function is used to study the stress/strain distribution state on the critical plane, and the relative stress gradient (RSG) function is used to find the stationary point to determine the RSG value and the magnitude of the fatigue damage zone boundary value. Specifically, for specimens with different notch types, the indexes to determine the high‐stress influence zone and the size influence factor are proposed. Finally, a multiaxial fatigue life prediction model considering RSG and size effect is established, and the compared results show that the new model has a high fatigue life prediction capability. Highlights: Relative stress gradient values and size of fatigue damage zone boundaries are determined by a sixth‐order multinomial stress function.A high‐stress influence zone index is proposed.The relationship between size effect and fatigue life is characterized.A fatigue life equation considering the relative stress gradient and the size effect is established. [ABSTRACT FROM AUTHOR]

Based on the density matrix theory of quantum system, the optimum operating parameters of pulsed optically pumped NH3 and CH3OH F-P cavity far-infrared laser (NH3/CH3OH-OPFIRL) were studied and compared theoretically. The differences of the operating parameters between the NH3-OPFIRL and CH3OH-OPFIRL were found and discussed. Experimentally, the curves of output power verses gas pressure in NH3 and CH3OH F-P cavity lasers pumped by TEA-CO2 laser were measured, and the optimum operating gas pressure were obtained. The experimental results were in agreement with theoretical calculations. [ABSTRACT FROM AUTHOR]

A miniature FIR laser with a sample-tube in 10 or 20cm length were constructed, and the laser's cavity consisted of a pair of metallic meshes, with NH3 molecules as active medium pumped by a TEA-CO2 laser, a series of FIR laser lines were observed. By taking account of the properties of the Fabry-Perot cavity and the gain characteristics of Raman transitions in the miniature optically pumped FIR laser, the spectral characteristics of the FIR laser were studied. [ABSTRACT FROM AUTHOR]

The sorption of AuCl4 −,AuCl2 − and Au(S2O3)3- on δ-MnO2 was investigated at pH2–11.6, 0.01 mol/L and 0.1 mol/L NaNO3 solutions. At pH 4 in two electrolyte strength solutions, Au sorption densities on δ-MnO2 are 0.18–0.21 and 0.28 μmoL/m2 for AuCl4 − and Au(S2O3)2 3-, respectively, and the Au surface coverage is approximate to or lower than 1%. This adsorption of the two Au complexes decreases as the solution pH increases, which conforms to the sorption regularity of the anion on δ-MnO2. The Au sorption decreases in the sequence of Au(S2O3)2 3- >AuCl4 − >AuC12 −. The intrinsic equilibrium constants (log K int) of the three Au complexes are 1.17–2.7, much higher than those of Cu and Cd. The hydrolysis products of AuCl4 - are preferentially adsorbed by δ-MnO2 and the inner-sphere Au-surface complexes are formed on the surface. [ABSTRACT FROM AUTHOR]

Based on the density matrix theory of quantum system, the spectra of optically pumped superradiant and cavity NH3 far-infrared (FIR) lasers were calculated by means of iteration method. The calculation showed that, compared with the optically pumped superradiant FIR laser, the cavity laser had a wider band spectrum of FIR emission and a higher output power under certain condition, moreover, the spectra of cavity laser had multi longitudinal-mode structure. [ABSTRACT FROM AUTHOR]

The distribution and bioconcentration of polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate material (SPM), algae, and zooplankton samples from the Pearl River Delta (PRD), South China, were investigated. The PAHs in the water and SPM samples is significantly associated with chlorophyll a (Chl a), implying the important role of the aquatic productivity on PAH distribution. PAHs in the water or SPM samples were strongly correlated to dissolved organic carbon (DOC) or algal particulate organic carbon (A-POC). Moreover, the log bioconcentration factor (BCF) values (mL g−1) of PAHs in both the algae and zooplankton samples were linearly related to their log octanol-water coefficient (Kow) values. However, the slopes of these relationships were negatively correlated with Chl a, attributing to the difference in the dominant plankton species or the non-equilibrium exchange between air-water-biota. The above results indicate the important role of trophic levels on the distribution and bioaccumulation of PAHs. Unlabelled Image • The phytoplankton OC contributed 36.7% of POC. • PAHs respectively showed significant correlations with DOC, POC, and Chl a. • Aqueous and particulate PAHs were strongly correlated to DOC or algal POC. • Log BCF values of PAHs in planktons were linearly related to their log K ow values. • Algal biomass played an important role on the partitioning and uptake of PAHs. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides have posed a great threat to non-target organisms, yet the mechanisms underlying their toxicity are not well characterized. Major modes of action (MoAs) of imidacloprid were analyzed in an aquatic insect Chironomus dilutus. Lethal and sublethal outcomes were assessed in the midges after 96-h exposure to imidacloprid. Global transcriptomic profiles were determined using de novo RNA-sequencing to more holistically identify toxicity pathways. Transcriptional 10% biological potency values derived from ranked KEGG pathways and GO terms were 0.02 (0.01–0.08) (mean (95% confidence interval) and 0.05 (0.04–0.06) μg L−1, respectively, which were more sensitive than those from phenotypic traits (10% lethal concentration: 0.44 (0.23–0.79) μg L−1; 10% burrowing behavior concentration: 0.30 (0.22–0.43) μg L−1). Major MoAs of imidacloprid in aquatic species were identified as follows: the activation of nicotinic acetylcholine receptors (nAChRs) induced by imidacloprid impaired organisms' nerve system through calcium ion homeostasis imbalance and mitochondrial dysfunction, which posed oxidative stress and DNA damage and eventually caused death of organisms. The current investigation highlighted that imidacloprid affected C. dilutus at environmentally relevant concentrations, and elucidated toxicity pathways derived from gene alteration to individual outcomes, calling for more attention to toxicity of neonicotinoids to aquatic organisms. Image 1 • Additional toxicity pathways of neonicotinoid to midges were identified. • Biological potency distribution curve provided sensitive pathway profiles. • The P path based on toxicogenomics could be a warning threshold for risk assessment. • Imidacloprid posed transcriptomic effect to midges at environment concentrations. Capsule: Transcriptomic analysis provides new insights to toxicity pathways of neonicotinoid insecticides to aquatic organisms and serves as an early warning tool for assessing aquatic risk. [ABSTRACT FROM AUTHOR]

The demineralized fraction (DM), lipid-free fraction (LF), nonhydrolyzable organic carbon fraction (NHC), and black carbon (BC) were isolated from five marine surface sediments, and they were characterized by elemental analysis as well as CO 2 and N 2 adsorption techniques, respectively. The NHC fractions were characterized using advanced solid-state 13C nuclear magnetic resonance (NMR) and x-ray photoelectron spectroscopy (XPS). Then, the sorption isotherms of phenanthrene (Phen) and nonylphenol (NP) on all of the samples were investigated by a batch technique. The CO 2 micropore volumes were corrected for the outer specific surface areas (SSAs) by using the N 2 -SSA. Significant correlations between the micropore-filling volumes of Phen and NP and the micropore volumes suggested that the micropore-filling mechanism dominated the Phen and NP sorption. Meanwhile, the (O + N)/C atomic ratios were negatively and significantly correlated with the sorption capacities of Phen and NP, indicating that the sedimentary organic matter (SOM) polarity also played a significant role in the sorption process. In addition, a strong linear correlation was demonstrated between the aromatic C and the sorption capacity of Phen for the NHC fractions. This study demonstrates the importance of the micropores, polarity, and aromaticity on the sorption processes of Phen and NP in the sediments. Image 1 • Sedimentary organic matter (NOM) was chemically fractionated into five fractions. • Structural and microporous properties were investigated using updated methods. • The sorption mechanism of phenanthrene (Phen) and noylphenol (NP) is expounded. • The sorption on black carbon is much higher for Phen than for NP. • Micropore-filling was the major mechanism for the sorption of Phen and NP. This study demonstrates the importance of the micropores, polarity, and aromaticity on the sorption processes of Phen and NP in marine sediments. [ABSTRACT FROM AUTHOR]

Dissolved, colloidal and particulate organic matter (DOM, COM and POM) is important in the global carbon cycle and knowledge of their sources and structures can be critical to understanding their roles in biogeochemical cycles. This study explored the sources and chemical structures of COM and POM samples from the Pearl River Basin, China by elemental, chlorophyll a (Chl a), radiocarbon and stable carbon isotopic analyses, NMR techniques, and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. The chemical and nano-sclae structures of two ultrafiltered dissolved organic matter (UDOM) samples from surface seawater of the Pacific and Atlantic Ocean were also studied by various advanced solid-state NMR techniques. The C/N ratios and δ13C values indicated that plankton and soil organic matter (SOM) were two major sources of COM and POM, whereas Chl a and radiocarbon analyses demonstrated the significant contribution of phytoplankton and ancient organic matter (OM) to COM and POM. The correlations among structural parameters, Chl a and Δ14C values suggested that phytoplankton significantly contribute to the COO/NC=O groups. The OCH3/NCH, nonpolar alkyl C and aromatic C-O groups could be derived from refractory and ancient OM, while O-alkyl C and di-O-alkyl C from labile and contemporary sources. FT-ICR MS analysis indicated that the main molecular composition of COM was CHO (56.44-62.83%), with the majority of the composition consisting of highly unsaturated compounds (more than 60%). This study for the first time provides the evidence that the chemical structures of COM and POM are influenced by trophic levels, and by their algal and ancient OM sources. We also discovered novel UDOM structures, which had wrongly been identifed before. It is interesting that sugar-bound COO groups are present in amounts similar to amino-acid residues and N-acetyl sugars, which has not been previously reported. Dissolved black carbon, polymethylene structure, and humified indices are estimated by the advanced techniques. [ABSTRACT FROM AUTHOR]

In addition to the adsorption and immobilization capacities of iron-modified biochars, these materials produce persistent free radicals (PFRs) that can carry out metal [i.e., Cr(VI)] redox transformations, but the primary forms and active species of PFRs involved are not well understood. Here, we investigated the key species of PFRs of α-Fe2O3-modified biochar (MBC) and their influence on Cr(VI) reduction under anaerobic conditions simulating paddy soil environments. MBC produced bulk phenoxyl PFRs that promoted Cr(VI) reduction due to the catalytic effect of the transition metal Fe. In addition, MBC was more efficient in reducing Cr(VI) under anaerobic conditions than under aerobic conditions due to the more active and accessible dissolved PFRs present in the dissolved organic matter (DOM). The electron transfer capacity of DOM was demonstrated by excitation-emission matrix (EEM) spectrophotometry combined with parallel factor analysis, which showed that the protein-like and humic-like components of DOM were involved in Cr(VI) reduction. Furthermore, Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) analysis indicated that reduced-S compounds (O/S < 4) and carboxylic acid (–COO) groups in the unsaturated aliphatic and lignin-like compounds are potentially the main active species accelerating Cr(VI) reduction under anaerobic conditions. Our results provide new insights into the role of dissolved PFRs from iron-modified biochar in promoting Cr(VI) reduction under anaerobic conditions such as flooded soils. Highlights: Iron modification promoted a 5.6-fold increase in the concentration of bulk phenoxyl PFRs over unmodified biochar. Dissolved PFRs in iron-biochar derived dissolved organic matter enhanced Cr(VI) reduction under anaerobic conditions. Reduced sulfur compounds and carboxylic acid groups were the major reducing species in the dissolved PFRs. [ABSTRACT FROM AUTHOR]

Lead and mercury are two of the most toxic heavy metals in environments. Mesosilicate-templated magnetic nanocarbons with ascorbic acid as carbon precursor were developed through nanocasting processes. The nanocarbon showed effective magnetic separation and the maximum adsorption capacity of 80.6 and 66.3 mg/g for Hg and Pb, respectively. Langmuir model well described adsorption processes of both Hg and Pb from water. Magnetic nanocarbon could be easily separated and incinerated, reducing the volume requiring the disposal. This study indicates that mesosilicate-templated nanocarbons with easy disposal potentials may be good candidates for cleansing Hg and Pb from contaminated water. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) were detected by gas chromatography–mass spectrometry in the sediment core form Poyang Lake. The concentrations of Σ17 PBDEs and Σ15 PAHs ranged from 1.13 to 4.64 ng/g, and from 341 to 744 ng/g, respectively. The Rock-Eval test was conducted to obtain organic matter parameters such as total organic carbon (TOC), S2, and hydrogen index (HI). The value of TOC, S2, and HI showed an increasing trend from the bottom to the surface. Source analysis results showed that the source of PAHs was combustion. Moreover, the correlation analysis of PBDEs, PAHs, and annual average temperature with S2 and HI showed that BDE-202, BDE-201, BDE-183, and BDE-154 were negatively correlated with S2 and HI, while BDE-85 and BDE-47 were positively correlated. There was no significant correlations of PAHs with S2 and HI, which is related to the disturbance of sediments. It is interesting that significantly positive correlation of HI with five-year moving averages of the air temperature was demonstrated, demonstrating that the climate warming enhanced the increase of algae in the Poyang Lake. [ABSTRACT FROM AUTHOR]

Background: γ-Secretase is a multiprotein protease that cleaves amyloid protein precursor (APP) and other type I transmembrane proteins. It has two catalytic subunits, presenilins 1 and 2 (PS1 and 2). In our previous report, we observed subtle differences in PS1- and PS2-mediated cleavages of select substrates and slightly different potencies of PS1 versus PS2 inhibition for select γ-secretase inhibitors (GSIs) on various substrates. In this study, we investigated whether γ-secretase modulators (GSMs) and inverse γ-secretase modulators (iGSMs) modulate γ-secretase processivity using multiple different substrates. We next used HEK 293T cell lines in which PSEN1 or PSEN2 was selectively knocked out to investigate processivity and response to GSMs and iGSMs. Methods: For cell-free γ-secretase cleavage assay, recombinant substrates were incubated with CHAPSO-solubilized CHO or HEK 293T cell membrane with GSMs or iGSMs in suitable buffer. For cell-based assay, cDNA encoding substrates were transfected into HEK 293T cells. Cells were then treated with GSMs or iGSMs, and conditioned media were collected. Aβ and Aβ-like peptide production from cell-free and cell-based assay were measured by ELISA and mass spectrometry. Result: These studies demonstrated that GSMs are highly selective for effects on APP, whereas iGSMs have a more promiscuous effect on many substrates. Surprisingly, iGSMs actually appear to act as like GSIs on select substrates. The data with PSEN1 or PSEN2 knocked out HEK 293T reveal that PS1 has higher processivity and response to GSMs than PS2, but PS2 has higher response to iGSM. Conclusion: Collectively, these data indicate that GSMs are likely to have limited target-based toxicity. In addition, they show that iGSMs may act as substrate-selective GSIs providing a potential new route to identify leads for substrate-selective inhibitors of certain γ-secretase-mediated signaling events. With growing concerns that long-term β-secretase inhibitor is limited by target-based toxicities, such data supports continued development of GSMs as AD prophylactics. [ABSTRACT FROM AUTHOR]