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In the realm of structural health monitoring (SHM), understanding the expected behavior of a structure is vital for the timely identification of anomalous activities. Existing methods often model only the physical quantities of monitoring data, neglecting the corresponding temporal information. To address this, this paper presents an innovative deep learning framework that synergistically combines a BiLSTM model, fortified by a temporal pattern attention (TPA) mechanism, with time-encoded temperature and traffic-induced deflection-temporal patterns. The arithmetic optimization algorithm (AOA) is employed for optimal hyperparameter tuning, and incremental learning was implemented to enable real-time updates of the model. Based on the proposed framework, an anomaly detection method was subsequently developed. This method is bidirectional: it uses quantile loss to provide expected ranges for structural behavior, identifying isolated anomalies, while the windowed normalized mutual information (WNMI) based on multivariate kernel density estimation (MKDE) helps detect trend variability caused by decreases in structural stiffness. This framework and the anomaly detection method were validated using data from an operational cable-stayed bridge. The results demonstrate that the method effectively predicts structural behavior and detects anomalies, highlighting the critical role of temporal information in SHM. [ABSTRACT FROM AUTHOR]

Modern bridges are monitored by an increasing network of sensors that produce massive data for bridge performance prediction. Reasonably and dynamically predicting with monitored data for the time-variant reliability of the existing bridges has become one of the urgent problems in structural health monitoring (SHM). This study, taking the dynamic measure of structural stress over time as a time series, proposes a data assimilation approach to predicting reliability based on extreme stress data with cyclicity. To this aim, the objectives of this article are to present the following: (a) a Gaussian mixture model-based Bayesian cyclical dynamic linear model (GMM-BCDLM) based on extreme stress data with cyclicity and (b) a dynamic reliability prediction method in the combination of GMM-BCDLM and SHM data via first-order second-moment (FOSM) method. An in-service bridge for providing real-time monitored stress data is applied to illustrate the application and feasibility of the proposed method. Then, the effectiveness and prediction precision of the proposed models are proved to be superior compared to other prediction approaches to extreme stress data with cyclicity. [ABSTRACT FROM AUTHOR]

Aim: Left-behind children (LBC) now account for more than 1 in 5 Chinese children, and they often suffer from behavioural problems when their parents leave their rural homes to seek work in urban areas. The primary aim of this meta-analysis was to compare the incidence rates and factor scores of behavioural problems in LBC, who now account for more than one-fifth of Chinese children, and non-LBC.Methods: This systematic review and meta-analysis explored the children's characteristic behavioural problems using the Achenbach Child Behaviour Check List. A subgroup analysis was conducted to compare the different behavioural problems of LBC with different characteristics. The meta-analysis assessed 1405 papers and analysed 13 papers from 2007 to 2015, covering 10 264 LBC and 8909 non-LBC from 2 to 19 years of age.Results: The incidence rates of behavioural problems were higher in LBC than non-LBC. The highest risks were noted in boys aged between 6 and 11 years of age, who were more likely to be withdrawn and be affected by somatic complaints, schizophreniform disorder, compulsive behaviour and depression.Conclusion: Interventions and policies are urgently needed to tackle behavioural issues among LBC, especially high-risk males aged 6-11 years. [ABSTRACT FROM AUTHOR]

Inorganic divalent mercury complexes (Hg 2+ ) and monomethylmercury complexes (MeHg) are the main mercury species in aquatic systems and their toxicity to aquatic organisms is of great concern. Tetrahymena is a type of unicellular eukaryotic protozoa located at the bottom of food chain that plays a fundamental role in the biomagnification of mercury. In this work, the dynamic accumulation properties, toxicological characteristics and mechanisms of Hg 2+ and MeHg in five Tetrahymena species were evaluated in detail. The results showed that both Hg 2+ and MeHg were ingested and exhibited inhibitory effects on the proliferation or survival of Tetrahymena species. However, the ingestion rate of MeHg was significantly higher than that of Hg 2+ . The mechanisms responsible for the toxicity of MeHg and Hg 2+ were different, although both chemicals altered mitochondrial membrane potential (MMP). MeHg disrupted the integrity of membranes while Hg 2+ had detrimental effects on Tetrahymena as a result of the increased generation of reactive oxygen species (ROS). In addition, the five Tetrahymena species showed different capacities in accumulating Hg 2+ and MeHg, with T. corlissi exhibiting the highest accumulations. The study also found significant growth-promoting effect on T. corlissi under low concentration exposure (0.003 and 0.01 μg Hg/mL (15 and 50 nM)), suggesting different effect and mechanism that should be more closely examined when assessing the bioaccumulation and toxicity of mercury in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation. In this study, according to differences in morphological characteristics between ground roll and reflected waves, we use morphological component analysis based on two-dimensional dictionaries to separate ground roll and reflected waves. Because ground roll is characterized by low-frequency, low-velocity, and dispersion, we select two-dimensional undecimated discrete wavelet transform as a sparse representation dictionary of ground roll. Because of a strong local correlation of the reflected wave, we select two-dimensional local discrete cosine transform as the sparse representation dictionary of reflected waves. A sparse representation model of seismic data is constructed based on a two-dimensional joint dictionary then a block coordinate relaxation algorithm is used to solve the model and decompose seismic record into reflected wave part and ground roll part.The good effects for the synthetic seismic data and application of real seismic data indicate that when using the model, strong-energy ground roll is considerably suppressed and the waveform of the reflected wave is effectively protected. [ABSTRACT FROM AUTHOR]

Abstract: The surface properties of a granular activated carbon (GAC) were modified by dielectric barrier discharge (DBD) plasma to enhance its adsorption capacity to pentachlorophenol (PCP). Surface characteristics and adsorption capacity of GAC before and after DBD plasma modification were investigated. Results showed that the surface of GAC after plasma modification, especially N2 plasma, became smoother and the particulates on virgin GAC's surface were eliminated due to deposit effect of plasma. The N2 plasma modification reduced the specific surface area and surface oxygen-containing functional groups of GAC. In contrast, O2 plasma modification increased the specific surface area and introduced oxygen-containing groups. [Copyright &y& Elsevier]

The thermodynamics of micellization of the sulfobetaine (SB) amphoteric surfactants, that is N-alkyl- N, N-dimethyl-3-ammonio-1-propanesulfonate and N-alkyl- N, N-dimethyl-3-ammonio-1-butanesulfonate (the carbon atom number of the alkyl chain is 12, 14 and 16 respectively) in aqueous solution, have been studied by surface tension measurements with the temperature range from 298.15 to 318.15 K. The critical micelle concentrations (CMC) of SB n-3 and SB n-4 surfactants were determined from the drop-volume methods at different temperatures. The obtained results indicated that the values of critical micelle concentration strongly depended on the surfactants species and temperatures. Thermodynamic parameters ( $$ \Updelta G_{\text{mic}}^{ \circ } $$, $$ \Updelta H_{\text{mic}}^{ \circ } $$ and $$ \Updelta S_{\text{mic}}^{ \circ } $$) of the micelle formation were determined. The micellization was found to be enthalpy-driven at lower temperatures, while this process was entropy-driven at higher temperatures. The enthalpy-entropy compensation were also investigated. The compensation temperature T and $$ \Updelta H_{\text{mic}}^{*} $$ decreased, while $$ \Updelta S_{\text{mic}}^{*} $$ increased with the increase in the hydrophobic chain length. [ABSTRACT FROM AUTHOR]

We study the light propagation properties in a V-type three-level atomic system interacting with two independent broadband squeezed baths. Using the graphic method, the dependences of the absorption and the dispersion of the system on the coupling field strength, the incoherent pumping field strength and the intensity of the squeezed vacuum are analysed. The result shows that the probe pulse propagation can be changed from subluminal to superluminal speed [ABSTRACT FROM AUTHOR]

Abstract: The problem of online adaptive tuning of PI controllers in heating, ventilating and air conditioning (HVAC) systems is explored. A discharge air temperature (DAT) system is described by a first-order plus dead-time model. The model parameters were estimated online while the control remains in the closed-loop. H ∞ adaptive tuning rules were applied and new PI parameters were estimated. Both computer simulations and experimental responses were studied. The results show that the H ∞ adaptive PI (HIAPI) controller is able to track set-point changes, reject the effects of multiple disturbances and is robust to changes in model parameters. [Copyright &y& Elsevier]

Abstract: An integrated granular activated carbon (GAC) adsorption/dielectric barrier discharge (DBD) process was applied to the treatment of high concentration pentachlorophenol (PCP) wastewater. The PCP in water firstly was adsorbed onto GAC, and then the degradation of PCP and regeneration of exhausted GAC were simultaneously carried out by DBD. The degradation mechanisms and products of PCP loaded on GAC were analyzed by EDX, FT-IR and GC–MS. The results suggested that the Cin PCP adsorbed by GAC were cleaved by DBD plasma, and some dechlorination and dehydroxylation products were identified. The adsorption capacity of adsorption/DBD treated GAC could maintain relatively high level, which confirmed that DBD treatment regenerated the GAC for subsequent reuse. The adsorption of N2, Boehm titration and XPS were used to investigate detailed surface characterizations of GAC. It could be found that DBD plasma not only increased the BET surface area and pore volume in micropore regions, but also had remarkably impact on the distribution of the oxygen-containing functional groups of GAC. [Copyright &y& Elsevier]

Abstract: A novel process for regenerating activated carbon based on high active species (O3, OH, HO2, O2 and RO, etc.) generated by dielectric barrier discharge (DBD) oxidation was proposed. The method was assayed with granular activated carbon (GAC) exhausted with azo dye acid orange 7. The regeneration efficiency of this technique was evaluated, and the regeneration efficiencies could reach over 73% after five continuous regeneration cycles. The effects of DBD on the adsorption rate, the texture characteristic, the surface chemistry, and the adsorption capacity of GAC samples after different regeneration cycles were investigated. The adsorption rate remained stable after multi-successive regeneration cycles. The analysis of texture of GAC samples showed that the specific surface area and pore volume decreased after DBD regeneration cycles except for the first regeneration sample. It was observed that DBD also resulted in the increase of carboxylic functional groups of GAC''s surface. Furthermore, all adsorption equilibrium isotherms fitted the Freundlich model fairly well, which demonstrated DBD plasma did not appear to modify adsorption process but to shift the equilibrium towards lower adsorption concentrations. [Copyright &y& Elsevier]

Abstract: Adeno-associated virus (AAV) empty capsids typically co-purify with genome containing AAV2 vectors purified by column chromatography. This study describes a method to remove empty capsids from genome containing vector particles by anion exchange chromatography. The separation is based on the slightly less anionic character of empty particles compared to vectors. Detailed methods to achieve AAV2 vector purification and particle separation using cation exchange resin POROS 50HS followed by anion exchange resin Q-Sepharosexl are described. Chromatographic separation of AAV2 particles was achieved using gradients based on sodium acetate and ammonium acetate, and was optimal at pH 8.5. Efficient removal of particle surface nucleic acid impurities was found to be important to achieve good particle separation. In a large scale experiment performed using partially purified vector containing a mixture of 1.56×1014 vg and 2.52×1015 empty capsids as a starting material, the optimized anion exchange chromatography method resulted in a vector peak of 1.15×1014 vg containing 0.25×1014 empty capsids, corresponding to 74% vector yield and 86-fold reduction in empty capsids in the vector product. [Copyright &y& Elsevier]

Background: There is uncertainty about the best approaches for advanced airway management (AAM) and the effectiveness of adrenaline treatments in Out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate whether AAM and adrenaline administration provided by Emergency Medical Service (EMS) can improve the outcomes of OHCA.Methods: This study was a prospective analysis of collected data based on OHCA adult patients treated by the EMS in China from January 2019 to December 2020.The patients were divided into AAM group and no AAM group, and into subgroups according to whether adrenaline was used. The outcome was rate of return of spontaneous circulation (ROSC), survival to admission and hospital discharge.Results: 1533 OHCA patients were reported. The probability of ROSC outcome and survival admission in the AAM group was significantly higher, compared with no AAM group. The probability of ROSC outcome in the AAM group increased by 66% (adjusted OR: 1.66, 95%CI, 1.02-2.71). There were no significant differences in outcomes between the adrenaline and no adrenaline groups. The combined treatment of AAM and adrenaline increased the probability of ROSC outcome by 114% (adjusted OR, 2.14, 95%CI, 1.20-3.81) and the probability of survival to admission increased by 115% (adjusted OR, 2.15, 95%CI, 1.16-3.97).Conclusions: The prehospital AAM and the combined treatment of AAM and adrenaline in OHCA patients are both associated with an increased rate of ROSC. The combined treatment of AAM and adrenaline can improve rate of survival to admission in OHCA patients. [ABSTRACT FROM AUTHOR]

To reduce the thermal stress at the clad layer and further reduce the crack generation in the laser cladding process, a method of controlling the cracks at the clad layer by changing the laser energy density is proposed. Comparative thermal–mechanical coupling finite element analysis was performed on the uniform rectangular and convex shape beam spot cladding processes on plasma-sprayed MCrAlY coating through the numerical simulation method based on the ANSYS software. Results show that rapid heating and cooling characteristics, which are typical in laser processing, are manifested in the cladding process using a uniform rectangular spot, whereas a convex shape spot can exert preheating and slow cooling effects to a certain extent, thereby reducing the temperature gradient of the cladding and non-cladding zones. In addition, on the precondition of equivalent cladding effect, the thermal stress at the clad layer is also low, enabling the effective mitigation of the cracking tendency of the clad layer. Relative to the laser beam-shaped diffractive optical element special for design and manufacturing, superposing two uniform rectangular spots with different sizes and energy densities is a simpler and more effective method of obtaining a convex shape spot. [ABSTRACT FROM AUTHOR]

Optical-quality single-crystal LiB3O5 (LBO) nanowires are synthesized for the first time using a sol-gel method. The LBO nanowires possess diameters ranging from 200 to 800 nm and lengths of up to 200 μm, and exhibit excellent uniformity, smooth surfaces, and good mechanical properties. A typical propagating loss of 0.038 dB/μm at 532 nm is obtained for a 620 nm-diameter nanowire. This is a decrease of one order of magnitude compared with that of a β-BaB2O4 (BBO) nanowire with similar diameter, which makes the LBO nanowire a promising candidate to construct miniaturized nonlinear photonic devices. [ABSTRACT FROM AUTHOR]

Abstract The characteristic accumulation of late-stage differentiated CD8+ T cells is enhanced by lifelong latent cytomegalovirus (CMV) persistence, which makes it challenging to screen for subclinical biomarkers of immune aging in the elderly. We systematically identified predominantly preformed, long, noncoding RNAs (lncRNAs) as integrative biomarkers of CD8+ T cell aging in 14 elderly CMV carriers over 80 years of age. After sorting the CD28nullCD8+ T cell subset and its CD28bearingCD8+ counterpart in five nonagenarians, we profiled the differential expression of lncRNAs and genes in CD28nullCD8+ T cells via array detection. We focused on 11 differentially expressed antisense lncRNAs and cross-referenced them with previously identified age-accumulated lncRNAs to create a set of candidates in CD28nullCD8+T cells. We performed intracellular validation on the age-accumulated candidate lncRNAs paired with their antisense target genes using quantitative polymerase chain reaction (qPCR). Simultaneously, we sorted the CMV pp65 -specific CD8+ T cell subset and its counterpart from participant cells with the HLA-A-*0201 genotype. The validated age-accumulated lncRNAs in CD28nullCD8+ T cells were intracellularly cross-validated in CMV pp65 CD8+ T cells. Finally, we identified the immunity-related gene(s) that acted as potential target(s) to the cross-validated age-accumulated lncRNA(s), using bioinformatics techniques. The potential regulation of the final identified lncRNA-gene pair(s) was simultaneously predicted in two pathway-integrated networks. We concluded that expression of an age-accumulated lncRNA (NRON) was decreased, whereas that of its immunity-related target gene (NFAT) was increased, in both CD28nullCD8+ T cells and CMV pp65 CD8+ T cells of elderly individuals with persistent CMV infection. The identification of NRON as a potential biomarker suggests that NRON contributes to CMV-enhanced CD28nullCD8+ T cell aging by modulating phosphorylation and/or IL-4-dependent NFAT signaling. Highlights • Screen a subclinical biomarkers of CD8+ T cell aging which is episodically enhanced by lifelong latent cytomegalovirus (CMV) persistence in overlapped cells between CD28nullCD8+ T cells and CMV pp65 CD8+ T cells of elderly individuals with persistent CMV infection. • Systematically identify the predominantly preformed long noncoding RNA NRON as a potentially integrative biomarker for CMV-amplified CD8+ T cell accumulation during immune aging. • Predict that the reduced expression of NRON may contribute to CMV-amplified CD28nullCD8+ T cell accumulation by modulating phosphorylation and/or IL-4-dependent NFAT signaling. [ABSTRACT FROM AUTHOR]

We propose a method to obtain the refractive index of a transparent sphere from the fascinating phenomena of rainbows, which can be used as an interesting subject in the experimental courses of primary optics for undergraduate or high school students. The primary and secondary rainbows are reproduced on white walls and screens in the classroom with the sun and water drops replaced by the LED flashlight and K9 glass (one type of borosilicate glass) sphere respectively. The locations of the primary and secondary rainbows on the screen are measured, with the locations of the screen and sphere changed. By fitting the multiple measurements to the theoretical result using the least square method, the refractive index of the glass sphere, as an unknown parameter in the fitting process, is obtained. For both the primary and secondary rainbows, the locations of the red, yellow and purple bows are measured independently. Repetitive measurements give very stable and accurate output with the standard deviation ratio as low as 10âˆ'4 and the relative error all around 0.1% compared to the result obtained from special instruments in the literature. The fascinating phenomena and precise measurements enable this method to fully deepen the students’ understanding of the law of refraction and the application of the least square method. [ABSTRACT FROM AUTHOR]

Cancer is caused by the abnormal proliferation of local tissue cells under the control of many oncogenic factors. MicroRNAs (miRNAs) are a class of evolutionarily conserved, approximately 22-nucleotide noncoding small RNAs that influence transcriptional regulationby binding to the 3′-untranslated region of target messenger RNA. As a member of the miRNA family, miR-141 acts as a suppressor or an oncomiR in various cancers and regulates cancer cell proliferation, apoptosis, invasion, and metastasis through a variety of signaling pathways, such as phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) and constitutive activation of nuclear factor-κB (NF-κB). Target gene validation and pathway analysis have provided mechanistic insight into the role of this miRNA in different tissues. This review also outlines novel findings that suggest miR-141 may be useful as a noninvasive biomarker and as a therapeutic target in several cancers. • Regulatory mechanisms of miR-141 in cancer • Regulatory roles of miR-141 in various cancers • miR-141 as a tumor drug therapy • miR-141 as a drug resistance • miR-141 as a diagnostic marker of cancers [ABSTRACT FROM AUTHOR]

Abstract: A novel method for simultaneous determination of five estrogens and four androgens by online solid-phase extraction (SPE) coupled with high-performance liquid chromatography–tandem mass spectrometry (HPLC–ESI-MS/MS) in water samples was developed. An aliquot of 50mL water sample after filtration was injected directly into autosampler and the analytes were preconcentrated on a NG1 online SPE column. After cleanup step the analytes were eluted in back flush mode and then separated on a liquid chromatography column. The experimental parameters, such as sample loading flow rate, cleanup condition and elution time, were optimized in detail. Estrogens and androgens were detected in negative and positive mode, respectively. High ionization efficiency of all the analytes was achieved by adding of 1‰ ammonia in the mobile phase. The recoveries ranged from 31.8% to 119.0% and the inter-day RSDs ranged from 2.7% to 19.6%. The limits of detections (LODs) were between 0.1 and 2.5ng/L. The proposed method was successfully applied to the analysis of three types of water samples, including river water, influent and effluent water from a wastewater treatment plant (WWTP). The recoveries of androgens were not that good and a further study is being planned to improve the sensitivity for them. The proposed method is simple, sensitive and suitable for simultaneous analysis and monitoring of estrogens and androgens in water samples. [Copyright &y& Elsevier]

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Selenium (Se) is commonly recognized as a protective element with an antagonistic effect against mercury (Hg) toxicity. However, the mechanisms of this Hg–Se antagonism are complex and remain controversial. To gain insight into the Hg–Se antagonism, a type of unicellular eukaryotic protozoa ( Tetrahymena malaccensis , T. malaccensis ) was selected and individually or jointly exposed to two Hg and three Se species. We found that Se species showed different toxic effects on the proliferation of T. malaccensis with the toxicity following the order: selenite (Se(IV)) > selenomethionine (SeMeth) > selenate (Se(VI)). The Hg–Se antagonism in Tetrahymena was observed because the joint toxicity significantly decreased under co-exposure to highly toxic dosages of Hg and Se versus individual toxicity. Unlike Se(IV) and Se(VI), non-toxic dosage of SeMeth significantly decreased the Hg toxicity, revealing the influence of the Se species and dosages on the Hg–Se antagonism. Unexpectedly, inorganic divalent Hg (Hg 2 + ) and monomethylmercury (MeHg) also displayed detoxification towards extremely highly toxic dosages of Se, although their detoxifying efficiency was discrepant. These results suggested mutual Hg–Se detoxification in T. malaccensis , which was highly dependent on the dosages and species of both elements. As compared to other species, SeMeth and MeHg promoted the Hg–Se joint effects to a higher degree. Additionally, the Hg contents decreased for all the Hg–Se co-exposed groups, revealing a sequestering effect of Se towards Hg in T. malaccensis . [ABSTRACT FROM AUTHOR]

Highlights: [•] A high ionization efficiency method for TBBPA derivatives detection was developed. [•] Trace levels (0.05μgL−1) of TBBPA derivatives can be detected directly. [•] A single detection needs only 1min. [•] Provide more possibilities for low polar molecules detection by MS. [ABSTRACT FROM AUTHOR]

This paper deals with the synthesis of a series of alkyl m-xylene sulfonate isomers (with the m-xylene located at the eighth carbon atom along the long alkyl chain) by the Friedel-Crafts reaction, and the Grignard reaction followed by hydrogenation. The structures were confirmed by H NMR. All analytical methods indicated high levels of purity of the isomers with the eighth carbon atom at the long alkyl chain. The critical micelle concentration (CMC), surface tension and maximum surface excess concentration at the CMC and area per molecule at the interface were determined. As the long alkyl chains increased the surfactant molecule tends to pack closely at the gas-liquid interface. Accordingly, the CMC decreased, the adsorption density increased, and the surface tension reduction was strengthened. [ABSTRACT FROM AUTHOR]

Abstract: Column chromatography has been described for purification of recombinant adeno-associated viral vectors (rAAV) serotypes 1, 2, 5, 6 and 8. Some of these purification processes have been used in manufacturing pre-clinical grade and clinical grade rAAV vectors. Recently, recombinant AAV9 has been reported to be highly efficient in transducing cardiac muscle in animal models. Systemic or cardiac gene delivery and other applications may require large quantities of rAAV9 vectors, thus a scalable method supporting large scale purification of rAAV9 is needed for clinical development. However, column chromatography-based purification has not been reported to date for rAAV9. This study reports a polyethylene glycol (PEG) modulated chromatography process for purification of AAV9 vectors. Inclusion of PEG in chromatography buffers modulated rAAV9 elution profiles in a manner that resulted in significantly improved resin binding capacity, vector purity and yield. PEG-modulated methods were developed and optimized for hydroxyapatite and ion exchange chromatography, and shown to result in vectors of high purity and functional activity. [Copyright &y& Elsevier]

Abstract: Aggregation of recombinant AAV2 results in reduced yield during purification and may have deleterious effects on vector transduction efficiency, biodistribution and immunogenicity following in vivo administration. Studies to elucidate the mechanism of vector aggregation and methods to prevent its occurrence are reported. In excipient screening studies, the sugars sorbitol, sucrose, mannitol, trehalose, or glycerol at concentrations of up to 5% (w/v), or surfactants Tween 80 or Pluronic F68, did not prevent aggregation. Aggregation was prevented by the use of various salts at concentrations corresponding to solution ionic strengths of >200 mM. AAV2 vectors purified by double cesium chloride gradient centrifugation, cation-exchange chromatography, or combined chromatography and gradient centrifugation each demonstrated a similar requirement for ionic strength to prevent aggregation. AAV2 vectors concentrated to 6.7 × 1013 vector genome (vg)/mL in neutral-buffered isotonic saline resulted in 59 ± 6.0% recovery of nonaggregated material compared to 96 ± 4.4% recovery in an isotonic formulation with elevated ionic strength. The latter showed no aggregation following storage or after 10 freeze–thaw cycles at −20°C. AAV2 vectors stored for an extended period in an elevated ionic strength formulation retained a high infectivity titer (13 vg/infectious unit) and transduction efficiency. Nuclease digestion of purified AAV2 vectors reduced aggregation, implicating trace amounts of vector surface nucleic acids in interparticle binding. [Copyright &y& Elsevier]

Identification of novel brominated contaminants in the environment, especially the derivatives and byproducts of brominated flame retardants (BFRs), has become a wide concern because of their adverse effects on human health. Herein, we qualitatively and quantitatively identified three byproducts of tetrabromobisphenol-S bis(2,3-dibromopropyl ether) (TBBPS-BDBPE), including TBBPS mono(allyl ether) (TBBPS-MAE), TBBPS mono(2-bromoallyl ether) (TBBPS-MBAE) and TBBPS mono(2,3-dibromopropyl ether) (TBBPS-MDBPE) as novel brominated contaminants. Meanwhile, the mass spectra and analytical method for determination of TBBPS-BDBPE byproducts were presented for the first time. The detectable concentrations (dry weight) of TBBPS-MAE, TBBPS-MBAE and TBBPS-MDBPE were in the ranges 28-394 μg/g in technical TBBPS-BDBPE and 0.1-4.1 ng/g in mollusks collected from the Chinese Bohai Sea. The detection frequencies in mollusk samples were 5%, 39%, 95% for TBBPS-MAE, TBBPS-MBAE and TBBPS-MDBPE, respectively, indicating their prevailing in the environment. The results showed that they could be co-produced and leaked into the environment with production process, and might be more bioaccumulative and toxic than TBBPS-BDBPE. Therefore, the production and use of TBBPS derivatives lead to unexpected contamination to the surrounding environment. This study also provided an effective approach for identification of novel contaminants in the environment with synthesized standards and Orbitrap high resolution mass spectrometry. [ABSTRACT FROM AUTHOR]