Sulfurized nano zero-valent iron prepared via different methods: Effect of stability and types of surface corrosion products on removal of 2,4,6-trichlorophenol.

Sulfurization improves the stability and activity of nano zero-valent iron (nZVI). The sulfurized nZVI (S-nZVI) were prepared with ball milling, vacuum chemical vapor deposition (CVD) and liquid-phase reduction techniques and the corresponding products were the mixture of FeS2 and nZVI (nZVI/FeS2), well-defined core-shell structure (FeSx@Fe) or seriously oxidized (S-nZVI(aq)), respectively. All these materials were applied to eliminate 2,4,6-trichlorophenol (TCP) from water. The removal of TCP was irrelevant with the structure of S-nZVI. Both nZVI/FeS2 and FeSx@Fe showed remarkable performance for the degradation of TCP. S-nZVI(aq) possessed poor mineralization efficiency to TCP due to its bad crystallinity degree and severe leaching of Fe ions, which retarded the affinity of TCP. Desorption and quenching experiments suggested that TCP removal by nZVI and S-nZVI was based on surface adsorption and subsequent direct reduction by Fe0, oxidation by in-situ produced ROS and polymerization on the surface of these materials. In the reaction process, the corrosion products of these materials transformed into crystalline Fe3O4 and α/ß-FeOOH, which enhanced the stability of nZVI and S-nZVI materials and was conductive to the electron transferring from Fe0 to TCP and strong affinity of TCP onto Fe or FeSx phases. All these were contributed to high performance of nZVI and sulfurized nZVI in removal and minerazilation of TCP in continuous recycle test.

Automatic analysis of integrated magnetic resonance and positron emission tomography images improves the accuracy of detection of focal cortical dysplasia type IIb lesions.

We aimed to develop an efficient and objective pre-evaluation method to identify the precise location of a focal cortical dysplasia lesion before surgical resection to reduce medication use and decrease the post-operative frequency of seizure attacks. We developed a novel machine learning-based approach using cortical surface-based features by integrating MRI and metabolic PET to identify focal cortical dysplasia lesions. Significant surface-based features of 22 patients with histopathologically proven FCD IIb lesions were extracted from PET and MRI images using FreeSurfer. We modified significant parameters, trained and tested the XGBoost model using these surface-based features, and made predictions. We detected lesions in all 20 patients using the XGBoost model, with an accuracy of 91%. We used one-way chi-squared test to test the null hypothesis that the population proportion was 50% (p = 0.0001), indicating that our classification of the algorithm was statistically significant. The sensitivity, specificity, and false-positive rates were 93%, 91%, and 9%, respectively. We developed an objective, quantitative XGBoost classifier that combined MRI and PET imaging features to locate focal cortical dysplasia. This automated method yielded better outcomes than conventional visual analysis and single modality quantitative analysis for surgical pre-evaluation, especially in subtle or visually unidentifiable FCD lesions. This time-efficient method would also help doctors identify otherwise overlooked details.

Photo- and Oxygen- Synergistically Controlled Selective Expression of Organic Phosphorescence Units.

Dynamic control of ultralong organic room-temperature phosphorescence (UORTP) is a charming target. Herein, we report a stimuli-responsive phosphorescence unit 7H-indolo[2,3-c]quinoline (NBCz) and its derivatives (PCBNBCz, FSO2NBCz, and N2BCzSO2NBCz) that show photo- and oxygen- synergistically induced afterglow activation and afterglow color change in the PMMA film. PCBNBCz and FSO2NBCz feature a donor-acceptor (D-A) structure, and N2BCzSO2NBCz features acceptor-bridged two different phosphorescence units (NBCz and N2BCz). The photoactivated UORTP of PCBNBCz and FSO2NBCz arises from the photoinduced consumption of oxygen in the PMMA film. It is clear that the phosphorescence unit NBCz contributes to subsequent photoinduced UORTP color change because the NBCz-doped PMMA film shows the same UORTP color change process. ESR and HRMS measurements confirmed that oxidation of NBCz occurs at the nitrogen atom of the quinoline ring via photogenerated superoxide radicals, which results in the UORTP color change. TDDFT calculations proved that after oxidation of NBCz, the T1 energy level declines significantly. Furthermore, photocontrolled selective expression of phosphorescence units is achieved in the case of N2BCzSO2NBCz. After further UV irradiation, oxidation of NBCz happened, and the oxidized form N2BCzSO2NBCz-O emitted the intrinsic orange UORTP of NBCz-O selectively and screened the intrinsic yellowish-green UORTP of N2BCz. Finally, multilevel photolithography can be demonstrated based on the photoactivated UORTP and the photoinduced UORTP color change. This work may give a deep insight into organic phosphorescence and pave a simple way for the development of stimulus-responsive smart UORTP materials.

A hierarchical dynamic Bayesian learning network for EMG-based early prediction of voluntary movement intention.

Decoding human action intention prior to motion onset with surface electromyograms (sEMG) is an emerging neuroengineering topic with interesting clinical applications such as intelligent control of powered prosthesis/exoskeleton devices. Despite extensive prior works in the related fields, it remains a technical challenge due to considerable variability of complex multi-muscle activation patterns in terms of volatile spatio-temporal characteristics. To address this issue, we first hypothesize that the inherent variability of the idle state immediately preceding the motion initiation needs to be addressed explicitly. We therefore design a hierarchical dynamic Bayesian learning network model that integrates an array of Gaussian mixture model - hidden Markov models (GMM-HMMs), where each GMM-HMM learns the multi-sEMG processes either during the idle state, or during the motion initiation phase of a particular motion task. To test the hypothesis and evaluate the new learning network, we design and build a upper-limb sEMG-joystick motion study system, and collect data from 11 healthy volunteers. The data collection protocol adapted from the psychomotor vigilance task includes repeated and randomized binary hand motion tasks (push or pull) starting from either of two designated idle states: relaxed (with minimal muscle tones), or prepared (with muscle tones). We run a series of cross-validation tests to examine the performance of the method in comparison with the conventional techniques. The results suggest that the idle state recognition favors the dynamic Bayesian model over a static classification model. The results also show a statistically significant improvement in motion prediction accuracy by the proposed method (93.83±6.41%) in comparison with the conventional GMM-HMM method (89.71±8.98%) that does not explicitly account for the idle state. Moreover, we examine the progress of prediction accuracy over the course of motion initiation and identify the important hidden states that warrant future research.

How Matrixes Influence Room Temperature Ultralong Organic Phosphorescence: 4-Dimethylaminopyridine vs Carbazole Derivative.

How matrixes influence room temperature ultralong organic phosphorescence (RTUOP) in the doping systems is a fundamental question. In this study, we construct guest-matrix doping phosphorescence systems by using the derivatives (ISO2N-2, ISO2BCz-1, and ISO2BCz-2) of three phosphorescence units (N-2, BCz-1, and BCz-2) and two matrixes (ISO2Cz and DMAP) and systematically investigate their RTUOP properties. Firstly, the intrinsic phosphorescence properties of three guest molecules were studied in solution, in the pure powder state, and in PMMA film. Then, the guest molecules were doped into the two matrixes with increasing weight ratio. To our surprise, all of the doping systems in DMAP feature a longer lifetime but weaker phosphorescence intensity, while all of the doping systems in ISO2Cz exhibit a shorter lifetime but higher phosphorescence intensity. According to the single-crystal analysis of the two matrixes, resemblant chemical structures of the guests and ISO2Cz enable them to approach each other and interact with each other via a variety of interactions, thus facilitating the occurrence of charge separation (CS) and charge recombination (CR). The HOMO-LUMO energy levels of the guests match well with the ones of ISO2Cz, which also significantly promotes the efficiency of the CS and CR process. To our best knowledge, this work is a systematic study on how matrixes influence the RTUOP of guest-matrix doping systems and may give deep insight into the development of organic phosphorescence.

A Class of Organic Units Featuring Matrix-Controlled Color-Tunable Ultralong Organic Room Temperature Phosphorescence.

A novel class of organic units (N-1 and N-2) and their derivatives (PNNA-1 and PNNA-2) with excellent property of ultralong organic room temperature phosphorescence (UORTP) is reported. In this work, N-1, N-2, and their derivatives function as the guests, while organic powders (PNCz, BBP, DBT) and polymethyl methacrylate (PMMA) serve as the host matrixes. Amazingly, the color of phosphorescence can be tuned in different states or by varying the host matrixes. At 77 K, all molecules show green afterglow in the monomer state but yellow afterglow in the aggregated state because strong intermolecular interactions exist in the self-aggregate and induce a redshift of the afterglow. In particular, PNNA-1 and PNNA-2 demonstrate distinctive photoactivated green UORTP in the PMMA film owing to the generation of their cation radicals. Whereas the PNNA-1@PNCz and PNNA-2@PNCz doping powders give out yellow UORTP, showing matrix-controlled color-tunable UORTP. In PNCz, the cation radicals of PNNA-1 and PNNA-2 can stay stably and form strong intermolecular interactions with PNCz, leading to a redshift of ultralong phosphorescence.

Achieving Colorful Ultralong Organic Room-Temperature Phosphorescence by Precise Modification of Nitrogen Atoms on Phosphorescence Units.

We successfully tune ultralong organic room-temperature phosphorescence (UORTP) by a simple strategy of precisely modifying nitrogen atoms on Phosphorescence Units, and colorful ultralong phosphorescence can be achieved. We for the first time investigate the structure-function relationship between phosphorescence properties and molecular structures of Phosphorescence Units. With BCz and BCz-1 as comparison, eight new Phosphorescence Units were synthesized by introducing one or two nitrogen atoms to the naphthalene moiety. For all the 10 Phosphorescence Units, their room-temperature ultralong phosphorescence in the PMMA film should be assigned to monomer phosphorescence from intrinsic T1 decay. For Phosphorescence Units series I (BCz, NBCz-1, NBCz-2, NBCz-3, NBCz-4, NBCz-5, and NBCz-6), introducing one nitrogen atom to the naphthalene moiety can significantly affect the phosphorescence properties of Phosphorescence Units, and the effect is quite complicated. For modification on the inner ring, the T1 energy level of NBCz-1 decreases, and the red shift of UORTP occurs while the T1 energy level of NBCz-2 increases and the blue shift of UORTP happens. For modification on the outer ring, no phosphorescence color change is observed for NBCz-3 and NBCz-4, but their phosphorescence lifetimes vary notably due to different intersystem crossing efficiencies; as the modification site approaches the central five-member ring, the T1 energy levels of NBCz-5 and NBCz-6 decrease, and their UORTP red shifts dramatically. For Phosphorescence Units series II (BCz, 2NBCz, BCz-1, and 2NBCz-1), introducing two nitrogen atoms to the outer six-member ring reduces energy level of T1 excitons and leads to incredible red shift of UORTP for BCz and 2NBCz while surprisingly energy levels of T1 excitons rise and UORTP blue shifts for BCz-1 and 2NBCz-1. Under the condition of proper modification sites, it is true that the more the additional nitrogen atoms, the more red-shifted the ultralong phosphorescence. This study may expand our knowledge of organic phosphorescence and lay the foundation for its future applications.

More than Carbazole Derivatives Activate Room Temperature Ultralong Organic Phosphorescence of Benzoindole Derivatives.

The mechanism of carbazole (Cz)-based phosphors is still unclear since its isomer (1H-benzo[f]indole, Bd) is discovered in 2020. Herein, the successful synthesis of four Cz/Bd derivatives is reported, named as 2CzBr, CzBdBr, 2BdBr, and 3Bd, and the general mechanism for their ultralong organic phosphorescence (UOP) is provided. Bd and its derivatives give double groups of phosphorescence, including the short-wavelength phosphorescence with a short lifetime and the ultralong phosphorescence at long wavelengths, assigned to their neutral molecules and radical cations, respectively. Interestingly, the doped poly(methyl methacrylate) (PMMA) films of CzBdBr and 2BdBr show photo-activated ultralong phosphorescence at room temperature. The activation of Bd derivatives 'UOP involves three factors: 1) well dispersion in the matrix with limited amount, 2) generation of their radical cations and 3) the matrix-mediated stabilization of radical cations. The function of Cz derivatives to activate the Bd derivatives' UOP could be replaced by photo-activation or using other matrixes. Significantly, the application of the doped PMMA films is practiced and gives an exciting result that the high-resolution QR code could be reversibly printed and erased on the film. This research has expanded the understanding in the field of organic phosphorescence and it may pave a new way for its development.

Association of Migraine with Its Comorbidities and Food Specific Immunoglobulin G Antibodies and Inflammatory Cytokines: Cross-Sectional Clinical Research.

PURPOSE: The relationship between food allergy caused by food specific IgG antibodies and migraine has received increased attention in recent years. Here, we aimed to evaluate the effects of food specific IgG antibodies on headache, gastrointestinal symptoms, anxiety, depression, sleep disorders, dermatosis, and serum inflammatory cytokines in migraine patients, and to quantitatively assess the effect of IgG levels on the severity of headache and its comorbidities. METHODS: Of 89 migraine patients, those who had one or more food specific IgG antibodies ≥50 U/mL were classified into the IgG positive group, which was then further divided into subgroups based on differing numbers of food allergens. All other subjects were classified into the IgG negative group. We compared the frequency and severity of migraine, anxiety, depression, sleep disorders, dermatosis, and inflammatory cytokines between groups. A regression model was performed to further assess the effect of overall positive IgG concentration and the mediation effect of inflammatory cytokines. RESULTS: Participants in the positive IgG group (n = 67) were more likely to have longer time elapsed since diagnosis, more frequent and severe migraine, a higher risk of developing anxiety and gastrointestinal symptoms, along with higher IL-6 and TNF-α. Subgroups with more food allergens generally had worse conditions as well. After adjusting for the inflammatory cytokines, the effect of IgG was reduced. CONCLUSION: Migraine patients with positive food specific IgG antibodies had worse migraine, anxiety, and gastrointestinal symptoms. Inflammatory cytokines partially mediate the causal pathway between food specific IgG antibodies, migraine, and migraine comorbidities.