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The longevity and reusability of N95‐grade filtering facepiece respirators (N95 FFRs) are limited by consecutive donning and disinfection treatments. Herein, we developed stable N97 nanofibrous respirators based on chemically modified surface to enable remarkable filtration characteristics via polarity driven interaction. This was achieved by a thin‐film coated polyacrylonitrile nanofibrous membrane (TFPNM), giving an overall long‐lasting filtration performance with high quality factor at 0.42 Pa−1 (filtration efficiency: over 97 %; pressure drop: around 10 Pa), which is higher than that of the commercial N95 FFRs (0.10–0.41 Pa−1) tested with a flow rate of 5 L min−1 and the 0.26 μm NaCl aerosol. A coxsackie B4 virus filtration test demonstrated that TFPNM also had strong virus capture capacity of 97.67 %. As compared with N95 FFRs, the TFPNM was more resistant to a wider variety of disinfection protocols, and the overall filtration characteristics remained N97 standard., A polarity‐driven air filtration approach is achieved based on the thin‐film coated PAN nanofibrous membranes (TFPNMs), possessing a superior filtration efficiency reaching to N97 grade with outstanding longevity and reusability compared with the N95 FFRs. The TFPNMs can be reused upon various disinfection treatments, giving great potential for personal health care.

NF‐κB, a critical cytokine of inflammatory bowel diseases (IBD), is a viable marker to reflect the inflammatory activity of the intestine. We aimed to develop NF‐κB‐targeted microbubbles (MBs) and perform molecular contrast‐enhanced ultrasound (CEUS) to quantify NF‐κB expressions on the intestinal wall in IBD mice in vivo. In this study, NF‐κB‐targeted MBs were fabricated by connecting biotin‐loaded NF‐κB antibodies and avidin‐loaded MBs. NF‐κB‐targeted MBs presented as transparent and round bubbles with an average diameter of 1.03/μm±0.01. The specific binding of targeted MBs and inflammatory cells was validated by in vitro experiments, including flow cytometry, Western blot and immunofluorescence, which revealed the specific binding of targeted MBs and inflammatory cells. Subsequently, NF‐κB‐targeted CEUS imaging was performed on mice with chemical‐induced colitis, and the peak intensity (PI) and time‐to‐peak (TTP) were quantified. Pathological and immunohistochemical (IHC) examinations were further implemented. For the target CEUS group, fast enhancement followed by slow subsiding was observed. The PI of target CEUS of the IBD mice was significantly higher than that of non‐target CEUS of the IBD mice, healthy controls and target CEUS of the treated IBD mice (34835%[13379–73492%] VS 437%[236–901%], 130%[79–231%], 528%[274–779%], p

Despite much progress has been made in the asymmetric α-arylation reactions of cyclic ketones, lactones and lactams, the enantioselective α-arylation of acyclic carbonyl compounds lagged much behind due to the in situ generated Z/E-enolate intermediates leading to opposite enantiomers. Especially, the asymmetric α-arylation of acyclic aldehydes is a long-standing challenge, because of the highest activity among carbonyl compounds leading to various competitive side reactions. Herein we reported an efficient Pd-catalyzed asymmetric intermolecular α-arylation reaction of α-alkyl-α-aryl disubstituted aldehydes with aryl bromides, which provides a rapid access to chiral aldehydes bearing an α-all-carbon quaternary stereocenter in moderate to good yields with good er in most cases. In addition, a pair of enantiomers could be easily prepared with the use of the same ligand by exchanging the aryl groups of aldehyde and aryl bromide.

PURPOSE: To develop 3D MRI methods for cerebral blood volume (CBV) and venous cerebral blood volume (vCBV) estimation with whole-brain coverage using Fourier-transform based velocity-selective (FT-VS) pulse trains. METHODS: For CBV measurement, FT-VS saturation (FT-VSS) pulse trains were employed to suppress static tissue while CSF contamination was corrected voxel-by-voxel using a multi-readout acquisition and a fast CSF T(2) scan. The vCBV mapping was achieved by inserting an arterial-nulling module which included a FT-VS inversion (FT-VSI) pulse train. Using these methods, CBV and vCBV maps were obtained on six healthy volunteers at 3T. RESULTS: The mean CBV and vCBV values in gray matter and white matter in different areas of the brain showed high correlation (r = 0.95 and p < 0.0001). The averaged CBV and vCBV values of the whole-brain were 5.4±0.6 and 2.5±0.3 mL/100g in gray matter, and 2.6±0.5 and 1.5±0.2 mL/100g in white matter, respectively, comparable to the literature. CONCLUSION: The feasibility of FT-VS based CBV and vCBV estimation was demonstrated for 3D acquisition with large spatial coverage.

The aim of this systematic review was to characterize the clinical features of adults with Salmonella osteomyelitis and summarize diagnosis and treatment methods to provide guidance for clinicians. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. We conducted a literature search in the PubMed, EMBASE, and Cochrane Library databases. Article screening and data extraction were performed by two reviewers individually. All the included studies were independently evaluated by two reviewers using the Methodological Index for Non‐Randomized Studies (MINORS) criteria. A total of 67 articles published between 1970 and 2019 were selected, which include 69 patients with an average age of 47.5 years (range, 18–79).The majority of cases (47.76%) occurred in immunocompetent adults without common risk factors. Aspiration and biopsy cultures were all positive in Salmonella osteomyelitis patients who underwent aspiration or biopsy. All infections were monomicrobial, and a total of 12 different serotypes were identified. The three most commonly reported Salmonella serotypes were Salmonella typhi (19 cases), Salmonella typhimurium (12 cases), and Salmonella enteritidis (11 cases). Only 12 of the 67 cases in our data (17.91%) had diarrhea symptoms, and 44 of the 67 cases (65.67%) had fever symptoms. Fifty‐nine of the 67 cases (88.06%) had local inflammatory manifestations, such as erythema, swelling, and tenderness in the affected area. The commonly reported involved sites were the vertebrae, femur, and tibia. Antibiotic therapy alone was utilized in 30 cases, and 24 patients (80.00%) were eventually cured. In total, 75.68% of patients achieved satisfactory results after treatment with surgery and antibiotics. Third‐generation cephalosporins were most commonly utilized, and antibiotic treatment was administered for an average of 11.3 weeks (95% CI, 8.31–14.37 weeks). Salmonella osteomyelitis should be considered in patients without any common risk factors. Aspiration or biopsy can facilitate the identification of pathogens to guide antibiotic choice. Empirical therapy with a third‐generation cephalosporin is recommended until the susceptibility of the strain is determined., Results of the meta‐analysis.

Objective To evaluated the clinical outcomes of periprosthetic joint infection (PJI) patients with destination joint spacer compared with that of two‐stage revision. Methods From January 2006 to December 2017, data of PJI patients who underwent implantation with antibiotic‐impregnated cement spacers in our center due to chronic PJI were collected retrospectively. The diagnosis of PJI was based on the American Society for Musculoskeletal Infection (MSIS) criteria for PJI. One of the following must be met for diagnosis of PJI: a sinus tract communicating with the prosthesis; a pathogenis isolated by culture from two separate tissue or fluid samples obtained from the affected prosthetic joint; four of the following six criteria exist: (i) elevated ESR and CRP; (ii) elevate dsynovial fluid white blood cell (WBC) count; (iii) elevated synovial fluid neutrophil percentage (PMN%); (iv) presence of purulence in the affected joint; (v) isolation of a microorganism in one periprosthetic tissue or fluid culture; (vi) more than five neutrophilsper high‐power fields in five high‐power fields observed from histological analysis of periprosthetic tissue at ×400 magnification. Age, sex, body mass index (BMI), and laboratory test results were recorded. All patients were followed up regularly after surgery, the infection‐relief rates were recorded, Harris hip score (HHS) and knee society score (KSS) were used for functional evaluation, a Doppler ultrasonography of the lower limb veins was performed for complication evaluation. The infection‐relief rates and complications were compared between destination joint spacer group and two‐stage revision group. Results A total of 62 patients who were diagnosed with chronic PJI were enrolled, with an age of 65.13 ± 9.94 (39–88) years. There were 21 cases in the destination joint spacer group and 41 cases in the temporary spacer group, namely, two‐stage revision group (reimplantation of prosthesis after infection relief). The Charlson comorbidity index (CCI) in the destination joint spacer group was higher than that in the temporary spacer group, and this might be the primary reason for joint spacer retainment. As for infection‐relief rate, there were three cases of recurrent infection (14.29%) in the destination joint spacer group and four cases of recurrent infection (9.76%) in the two‐stage revision group, there were no significant differences with regard to infection‐relief rate. Moreover, there two patients who suffered from spacer fractures, three cases of dislocation, one case of a periarticular fracture, and three cases of deep venous thrombosis in destination joint spacer group, while there was only one case of periprosthetic hip joint fracture, one case of dislocation, and one patient suffered from deep venous thrombosis of the lower extremity in two‐stage revision. The incidence of complications in the destination joint spacer group was higher than that of two‐stage revision. Conclusions In summary, the present work showed that a destination joint spacer might be provided as a last resort for certain PJI patients due to similar infection‐relief rate compared with two‐stage revision., Diagram of destination joint spacer.

PURPOSE To evaluate both velocity and spatial responses of velocity-selective arterial spin labeling (VS-ASL), using velocity-insensitive and velocity-compensated waveforms for control modules, as well as a novel dynamic phase-cycling approach, at different B0 / B1+ field inhomogeneities. METHODS In the presence of imperfect refocusing, the mechanism of phase-cycling the refocusing pulses through four dynamics was first theoretically analyzed with the conventional velocity-selective saturation (VSS) pulse train. Numerical simulations were then deployed to compare the performance of the Fourier-transform based velocity-selective inversion (FT-VSI) with these three different schemes in terms of both velocity and spatial responses under various B0 / B1+ conditions. Phantom and human brain scans were performed to evaluate the three methods at B1+ scales of 0.8, 1.0, and 1.2. RESULTS The simulations of FT-VSI showed that, under nonuniform B0 / B1+ conditions, the scheme with velocity-insensitive control was susceptible to DC bias of the static spins as systematic error, while the scheme with velocity-compensated control had deteriorated velocity-selective labeling profiles and, thus, reduced labeling efficiency. Through numerical simulation, phantom scans, and brain perfusion measurements, the dynamic phase-cycling method demonstrated considerable improvements over these issues. CONCLUSION The proposed dynamic phase-cycling approach was demonstrated for the velocity-selective label and control modules with both velocity and spatial responses robust to a wide range of B0 and B1+ field inhomogeneities.

Green purchasing behavior is of great significance to the realization of carbon reduction goals. Through in‐depth interviews, this study uses new energy vehicles to explore the driving factors of green purchase. It applies grounded theory for a qualitative analysis, the results of which show that behavior motivation, behavior intentions, residential characteristics, social norms, behavior ability, and institutional and technological context are the main factors of green purchase, albeit in inconsistent ways. It is found that behavior motivation indirectly affects green purchase through behavior intention; residents' characteristics, behavioral ability, social norms, and the institutional and technological context have moderating effects on the relationship between behavior intention and green purchase, indicating the existence of an “intention–behavior” gap. The study proposes the comprehensive model of Motivation–Intention–Context–Behavior to explain the driving factors for green purchase and provides policy implications on marketing strategy to companies producing green products.

This paper utilizes a combined approach of the convection-diffusion theory and the moment analysis to conduct a comprehensive investigation of the solute dispersion under the influence of the interphase transport in finitely long inner coated microchannels. The present work has threefold novel contributions: (1) The 2D solute concentration contours in the stationary phase are calculated for the first time to facilitate the understanding the role of the interphase transport in the solute dispersion in the mobile phase. (2) The skewness of the elution curves is investigated to guide the control of solute band shape at the channel outlet. (3) The 2D diffusion-convection theory and zero-dimensional (0D) moment analysis complement each other to present a characterization of the solute dispersion behaviors more comprehensive than that by either of the two methods alone. Parametric studies are performed to clarify the effects of four major parameters related to the interphase transport (i.e., stationary phase Péclet number, interphase transport rate, partition coefficient, and stationary phase thickness) on the solute dispersion characteristics. The results from this study provide a straightforward understanding of the effects of interphase transport on the solute dispersion in finitely long microchannels and are of potential relevance to the design and operation of the microfluidics-based analytical devices.

Objective Fusobacterium nucleatum is an anaerobic gram‐negative bacilli that is one of the oral and other mucosal surface microbiota. It involves a wide range of human diseases and was first found in periodontal diseases, but reports of bone‐related infections caused by F. nucleatum are rare, especially periprosthetic joint infections (PJI). Methods Here, we present the first case of acute hematogenous PJI of the hip joint caused by F. nucleatum, and debridement, antibiotics, and implant retention (DAIR) was performed. Results The patient was successfully treated with DAIR, identification of isolates by metagenomics next‐generation sequencing was confirmed by polymerase chain reaction. Conclusions For stable acute hematogenous PJI after hip replacement, quick and accurate diagnosis, the identification of pathogenic microorganisms, and the use of DAIR combined with sufficient sensitive antibiotics have a certain clinical effect and can achieve the purpose of both preserving the prosthesis and infection control., Successful treatment of F. nucleatum PJI with DAIR (debridement, antibiotics, implant retention).

Osteogenic differentiation (OD) of bone marrow mesenchymal stem cells (BMSCs) is critically important for mitigation of osteoporosis. Glucocorticoids (GCs) are extensively used for treating chronic inflammation, although long-term exposure to GCs is capable of triggering osteoporosis. microRNAs (miRNAs) have been reported to play a critical role in bone diseases. In the present study, we treated BMSCs with dexamethasone (DEX) during OD to stimulate GC-mediated osteoporosis. Microarray and quantitative polymerase chain reaction (Q-PCR) assays demonstrated that miR-199a was upregulated during OD of BMSCs, while DEX treatment caused a significant reduction in miR-199a. Alkaline phosphatase (ALP) activity, Alizarin red (AR) staining, and Q-PCR were applied to assess the role of miRNA-199a overexpression in DEX-triggered OD inhibition. miR-199a was able to rescue OD and ALP activity, which were inhibited by DEX. Additionally, we observed that ALP, BMP2, COL1A1, and Runx2 were increased after transfection of miRNA-199a mimics. Furthermore, we confirmed that miRNA-199a facilitates OD of BMSCs through direct inhibition of Klotho protein and messenger RNA expression affecting the downstream fibroblast growth factor receptor 1/extracellular-signal-regulated kinase and Janus kinase 1/signal transducer and activator of transcription 1 pathways. This study indicates that miR-199a plays a critical role in preventing GC-mediated osteoblast differentiation and may function as a promising miRNA biomarker for osteoporosis.

During the past few decades, there has been considerable growth in the development of denitrogenative reactions of triazole skeletons to construct valuable cyclic compounds, particularly heterocycles. Despite the inherent difficulty of the ring-opening of triazole derivatives, many novel and efficient approaches have arisen in this area mainly with the use of transition metal (such as rhodium, palladium, silver, copper) catalysis, photolysis, or free radical mediated reactions. Generally, these procedures begin with the ring-opening of 1,2,3-triazoles or benzotriazoles followed by N2 extrusion and subsequent diverse transformations, which enable the rapid synthesis of various heterocycles in a single step. To avoid overlap with other related reviews, this minireview covers the recent advances in the denitrogenative cyclization of 1,2,3-triazoles since 2016 and the denitrogenative cyclization of benzotriazoles since 2012.

Reported here is a highly efficient Pd/Xiang-Phos catalyzed enantioselective carboetherification of alkenyl oximes with either aryl or alkenyl halides, delivering various chiral 3,5-disubstituted and 3,5,5-trisubstituted isoxazolines in good yields with up to 97 % ee. The sterically bulky and electron-rich (S,Rs)-NMe-X2 ligand is responsible for the excellent reactivities and enantioselectivities. The salient features of this transformation include mild reaction conditions, general substrate scope, good functional-group tolerance, good yields, high enantioselectivities, easy scale-up, and application in the late-stage modification of bioactive compounds. The obtained products can be readily transformed into useful chiral 1,3-aminoalcohols.

PURPOSE To evaluate different T2 -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA). METHODS Blood T2 values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T2 -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T2 values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated. RESULTS Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T2 calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T2 calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T2 calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers. CONCLUSION Our results confirm that sickle blood T2 values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T2 calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T2 -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.

Ephedrine (EPH) and pseudoephedrine (PSE) were studied by micro-Raman spectroscopy and UV resonance Raman spectroscopy excited at 785 and 360 nm, respectively. Raman bands at approximately 245 and 410 cm-1 for ephedrine have apparent differences from the same bands at approximately 215, 265, 350, 450, and 555 cm-1 for pseudoephedrine, and these differences can be applied to distinguish between EPH and PSE. Additionally, density functional theory was used for the Raman calculations to obtain results identical to the experimental spectra. This work is expected to expand the applications of Raman spectroscopy in forensic science.

PURPOSE Velocity-selective saturation (VSS) pulse trains provide a viable alternative to the spatially selective methods for measuring cerebral blood volume (CBV) by reducing the sensitivity to arterial transit time. This study is to compare the Fourier-transform-based velocity-selective saturation (FT-VSS) pulse trains with the conventional flow-dephasing VSS techniques for CBV quantification. METHODS The proposed FT-VSS label and control modules were compared with VSS pulse trains utilizing double refocused hyperbolic tangent (DRHT) and 8-segment B1-insensitive rotation (BIR-8). This was done using both numerical simulations and phantom studies to evaluate their sensitivities to gradient imperfections such as eddy currents. DRHT, BIR-8, and FT-VSS prepared CBV mapping was further compared for velocity-encoding gradients along 3 orthogonal directions in healthy subjects at 3T. RESULTS The phantom studies exhibited more consistent immunity to gradient imperfections for the utilized FT-VSS pulse trains. Compared to DRHT and BIR-8, FT-VSS delivered more robust CBV results across the 3 VS encoding directions with significantly reduced artifacts along the superior-inferior direction and improved temporal signal-to-noise ratio (SNR) values. Average CBV values obtained from FT-VSS based sequences were 5.3 mL/100 g for gray matter and 2.3 mL/100 g for white matter, comparable to literature expectations. CONCLUSION Absolute CBV quantification utilizing advanced FT-VSS pulse trains had several advantages over the existing approaches using flow-dephasing VSS modules. A greater immunity to gradient imperfections and the concurrent tissue background suppression of FT-VSS pulse trains enabled more robust CBV measurements and higher SNR than the conventional VSS pulse trains.

We report the characterization of rotaxanes based on a carbazole‐benzophenone thermally activated delayed fluorescence luminophore. We find that the mechanical bond leads to an improvement in key photophysical properties of the emitter, notably an increase in photoluminescence quantum yield and a decrease in the energy difference between singlet and triplet states, as well as fine tuning of the emission wavelength, a feat that is difficult to achieve when using covalently bound substituents. Computational simulations, supported by X‐ray crystallography, suggest that this tuning of properties occurs due to weak interactions between the axle and the macrocycle that are enforced by the mechanical bond. This work highlights the benefits of using the mechanical bond to refine existing luminophores, providing a new avenue for emitter optimization that can ultimately increase the performance of these molecules., We report rotaxanes containing a carbazole‐containing TADF luminophore in which the mechanical bond improves key photophysical properties, including the photoluminescence quantum yield and the singlet–triplet energy gap (ΔE ST). Computational simulations, supported by X‐ray crystallography, suggest this is due to weak interactions between the axle and macrocycle, enforced by the mechanical bond.