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Many challenges still exist in lithium–oxygen batteries (LOBs), particularly exploring an efficient catalyst to optimize the reaction pathway and regulate the Li2O2nucleation. Pr6O11has a unique 4f electronic structure and the highest oxygen ion mobility among rare earth oxides, exhibiting superior electronic, optical, and chemical properties. These unique properties might endow it with advanced catalytic activities for LOBs. This work reports two crystal forms of Pr6O11as novel catalysts and regulates the oxygen vacancy (Vo) concentrations by feasible calcination. Thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS) confirm the conversion from commercial Pr6O11to cubic fluorite Pr6O11and Vo-rich Pr6O11. Photographs, high-resolution transmission electron microscopy, selected area electron diffraction, XPS, and electron paramagnetic resonance robustly demonstrate the temperature-dependent evolution of Vo. Ex situXPS, scanning electron microscopy, and electrochemical techniques are used to study the catalytic mechanism and electrochemical reversibility. It is found that an appropriate Voconcentration can boost O2adsorption/desorption, accelerate electron transport, and reduce the reaction energy barrier. Vo-rich Pr6O11optimizes the reaction pathway by offering an intermediate Li2–xO2(with metalloid conductivity) and adjusting Li2O2into vertically staggered nanoflakes, effectively avoiding the suffocation of the catalytic surface and presenting excellent capacity, cycling stability, and rate performance.

Background: Burning temperature is one of the most important factors affecting the chemical structure of the smoke and the addition of reconstituted tobacco sheet to cut tobacco has been widely used by the tobacco industry to reduce the cost of cigarettes and the health risks of smoking. Methods: A flame retardant film, made from chitosan and ammonium polyphosphate, has been coated on the surface of the reconstituted tobacco sheet substrate by Layer-by-Layer and spray coating techniques. The thermal degradation properties and flame retardancy of these reconstituted tobacco sheets were analyzed by TG-FTIR and micro-scale combustion calorimetry. Results: It was found that the reconstituted tobacco sheet with the ratio of chitosan (5%) and ammonium polyphosphate (3%) film coating showed significant reductions in the peak heat release rate (50.7%), total heat release (35.8%) and the highest temperature in the temperature distribution diagram (77°C). The main gases released during the pyrolysis of these reconstituted tobacco sheet samples were H2O, CO2, CO, NH3, carbonyl compounds and the presence of film coating changed the formation of evolved volatile products and formed less gaseous products except NH3 during the thermal decomposition process. Conclusion: The coating film can greatly enhance the char forming ability and reduce the flammability of reconstituted tobacco sheet, and therefore, reduce the health risks of smoking with the addition of these reconstituted tobacco sheets.

Chemotherapy-induced premature ovarian failure (POF) in women is currently clinically irreversible. Bone marrow mesenchymal stem cells (BMSCs) are a promising cellular therapeutic strategy for POF. However, the underlying mechanism governing the efficacy of BMSCs in treating POF has not been determined. In this study, we show that BMSC and BMSC-derived exosome transplantation can significantly recover the estrus cycle, increase the number of basal and sinus follicles in POF rats, increase estradiol (E2) and anti-Mullerian hormone (AMH) levels, and reduce follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels in the serum. Furthermore, we demonstrate that BMSC-derived exosomes prevent ovarian follicular atresia in cyclophosphamide (CTX)-treated rats via the delivery of miR-144-5p, which can be transferred to cocultured CTX-damaged granulosa cells (GCs) to decrease GC apoptosis. A functional assay revealed that overexpression of miR-144-5p in BMSCs showed efficacy against CTX-induced POF, and the improvement in the repair was related to the inhibition of GC apoptosis by targeting PTEN. The opposite effect was exhibited when miR-144-5p was inhibited. Taken together, our experimental results provide new information regarding the potential of using exosomal miR-144-5p to treat ovarian failure.

The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to stimulate robust and durable adaptive immune protection is crucial, yet challenging. In this study, we synthesized a library of stimuli-responsive bivalent ionizable lipids (srBiv iLPs) with smart molecular blocks responsive to esterase, H2O2, cytochrome P450, alkaline phosphatase, nitroreductase, or glutathione (GSH), aiming to leverage physiological cues to trigger fast lipid degradation, promote mRNA translation, and induce robust antitumor immunity via reactive oxygen species (ROS)-mediated boosting. After subcutaneous immunization, esterase-responsive vaccine (eBiv-mVac) was rapidly internalized and transported into the draining lymph nodes. It then underwent fast decaging and self-immolative degradation in esterase-rich antigen-presenting cells, releasing sufficient mRNA for antigen translation and massive reactive quinone methides to elevate ROS levels. This resulted in broad activation of innate immunity to boost T cell response, prompting a large number of primed antigen-specific CD8+T cells to circulate and infiltrate into tumors (>1000-fold versus unvaccinated control), thereby orchestrating innate and adaptive immunity to control tumor growth. Moreover, by further combining our vaccination strategy with immune checkpoint blockade, we demonstrated a synergism that significantly amplified the magnitude and function of antigen-specific CD8+T cells. This, in turn, caused potent systemic antitumor efficacy and prolonged survival with high complete response rate in xenograft and metastasis models. Overall, our generalized stimuli-responsive mRNA delivery platform promises a paradigm shift in the design of potent vaccines for cancer immunotherapy, as well as effective and precise carriers for gene editing, protein replacement, and cell engineering.

Background: Transforming growth factor-β (TGF-β)/nodal signaling is involved in early embryonic patterning in vertebrates. Nodal modulator (Nomo, also called pM5) is a negative regulator of nodal signaling. Currently, the role of nomo gene in cartilage development in vertebrates remains unknown. Methods: Nomo mutants were generated in a knockout model of zebrafish by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) targeting of the fibronectin type III domain. The expression of related genes, which are critical for chondrogenesis, was analyzed by whole-mount in situ hybridization and qRT-PCR. Whole-mount alcian staining was performed to analyze the cartilage structure. Results: nomo is highly expressed in various tissues including the cartilage. We successfully constructed a zebrafish nomo knockout model. nomo homozygous mutants exhibited varying degrees of hypoplasia and dysmorphism on 4 and 5 dpf, which is similar to chondrodysplasia in humans. The key genes of cartilage and skeletal development, including sox9a, sox9b, dlx1a, dlx2a, osx, col10a1, and col11a2 were all downregulated in nomo mutants compared with the wildtype. Conclusion: The nomo gene positively regulates the expression of the master regulator and other key development genes involved in bone formation and cartilage development and it is essential for cartilage development in zebrafish.

Background: The acid extraction and enzymatic hydrolysis of starch followed by ion chromatography analysis are the tobacco industry standard methods in China which are very timeconsuming, troublesome, and moreover, there has no structure information of starch. This paper aims to develop an overall method for rapid extraction and simultaneous analysis of the content and structure of starch from flue-cured tobacco leaves by 13C CP/MAS NMR. Methods: The starch from flue-cured tobacco was extracted using pH=10 NaOH solution with the ratio of liquid to solid 30:1 for 90 min and analyzed on the basis of solid state 13C NMR spectroscopy. Its crystalline characteristics, relative crystallinity, proportion of double helices and content were estimated by peak fitting analysis of C-1, C-2,3,5, C-4 and C-6 regions of the spectra. Results: It was found that tobacco starch was B-type crystallinity and had the lowest double helix content and relative crystallinity compared with maize, sweet potato and lotus root starches. The quantitative result of internal standard method showed that the average recovery was 93.0% with the RSD of 3.2%~4.8%. Conclusion: This rapid and accurate NMR method could provide important information about both amount and structure of starch in tobacco.

Disruption of endothelial cell (ECs) and pericytes interactions results in vascular leakage in acute lung injury (ALI). However, molecular signals mediating EC–pericyte crosstalk have not been systemically investigated, and whether targeting such crosstalk could be adopted to combat ALI remains elusive. Using comparative genome-wide EC–pericyte crosstalk analysis of healthy and LPS-challenged lungs, we discovered that crosstalk between endothelial nitric oxide and pericyte soluble guanylate cyclase (NO–sGC) is impaired in ALI. Indeed, stimulating the NO–sGC pathway promotes vascular integrity and reduces lung edema and inflammation-induced lung injury, while pericyte-specific sGC knockout abolishes this protective effect. Mechanistically, sGC activation suppresses cytoskeleton rearrangement in pericytes through inhibiting VASP-dependent F-actin formation and MRTFA/SRF-dependent de novo synthesis of genes associated with cytoskeleton rearrangement, thereby leading to the stabilization of EC–pericyte interactions. Collectively, our data demonstrate that impaired NO–sGC crosstalk in the vascular niche results in elevated vascular permeability, and pharmacological activation of this crosstalk represents a promising translational therapy for ALI.

The VISION (video indexing for searching over networks) digital video library system has been developed in our laboratory as a testbed for evaluating automatic and comprehensive mechanisms for video archive creation and content-based search, filtering and retrieval of video over local and wide area networks. In order to provide access to video footage within seconds of broadcast, we have developed a new pipelined digital video processing architecture which is capable of digitizing, processing, indexing and compressing video in real time on an inexpensive general purpose computer. These videos were automatically partitioned into short scenes using video, audio and closed-caption information. The resulting scenes are indexed based on their captions and stored in a multimedia database. A client-server-based graphical user interface was developed to enable users to remotely search this archive and view selected video segments over networks of different bandwidths. Additionally, VISION classifies the incoming videos with respect to a taxonomy of categories and will selectively send users videos which match their individual profiles.

A new method utilizing 13C cross-polarization/magic angle spinning (CP/MAS) nuclear magnetic resonance (NMR) spectra was developed for the simultaneous quantitative determination and structure analysis of tobacco cellulose from hot water or acid detergent extraction. A reference spectrum of tobacco noncellulose components was subtracted from the spectrum of each sample to obtain a subspectrum of the cellulose components. The NMR spectra in combination with spectral fitting were analyzed in detail and some parameters, such as the content of cellulose, crystallinity, allomorph composition and lateral dimensions for cellulose elementary fibrils and microfibrils were determined. The quantitative results showed that the average recovery was 94.0% with a relative standard deviation (RSD) of 4.6–4.8%. The structure results obtained by the spectral fitting for the cellulose C1-region showed that the main allomorph composition in tobacco cellulose was Iβ. The cellulose crystallinity calculated by the spectral fitting in C4 -region was about 50%. The lateral dimensions for cellulose elementary fibrils and microfibrils were in the range of 3.0–6.0 nm and 6.0–13.0 nm, respectively. Therefore, this NMR method could provide important information on both amount and structure of cellulose in tobacco.

A new method utilizing 13C CP/MAS NMR spectra was developed for the simultaneous quantitative and structure analysis of pectin in tobacco. The conditions of acid extraction of tobacco samples and the parameters of spectral instruments were optimized. The C-6 carbon regions of NMR spectra were studied in detail, and the chemical shift and the area of peaks were applied for the calculation of polygalacturonic acid (PGA) content, degrees of methylation (DM) and degrees of acetylation (DAc). The quantitative results showed that the average recovery was 92.5% with a RSD of 4.4–4.9%. Therefore, this NMR method could provide important information about both the amount and structure of pectins.

Analysis of the urinary metabolite of benzo[a]pyrene (BaP), 3-hydroxybenzo[a]pyrene (3-OHBaP), is useful for the biomonitoring of carcinogenic polycyclic aromatic hydrocarbons (PAHs) exposure. The determination of 3-OHBaP by liquid chromatography tandem mass spectrometry (LC-MS/MS) suffers from the poor sensitivity of detection in commonly used electrospray ionization (ESI) sources. In this study, a sensitive and selective LC-MS/MS method was developed for the determination of urinary 3-OHBaP. Following enzymatic hydrolysis of the glucuronide and sulfate conjugates, the metabolite was enriched and cleaned up by solid-phase extraction and then derivatized with dansyl chloride. The derivative was analyzed by LC-MS/MS with ESI in the positive ion mode. The derivatization of 3-OHBaP by the introduction of a dansyl group into the molecule greatly enhanced the detection sensitivity by improving both the efficiency of ESI in the positive ion mode and collision-induced dissociation in the collision cell. Good linearity was obtained in the range of 0.25–40.0 pg mL−1with a correlation coefficient (r2) of 0.9924. The limit of detection (LOD) and lower limit of quantification (LLOQ) were 0.1 pg mL−1and 0.25 pg mL−1, respectively. Accuracy ranged from 87.7% to 107.5%. Intra- and inter-day relative standard deviations varied from 4.6% to 8.4% and 7.2% to 10.6%, respectively. Finally, this developed method was successfully applied for the analysis of urine samples from smokers and non-smokers to measure human exposure to PAHs.

A new ultrasound-assisted extraction (UAE) followed by dispersive liquid–liquid microextraction (DLLME) method has been developed for the simultaneous determination of flavoring compounds, including safrole, coumarin, 6-methylcoumarin, 7-metheoxycoumarin, estragole, methyleugenol, pulegone and thujone, in tobacco additives. In this method, the targets were extracted from tobacco additive sample using ethanol by UAE. Then, 0.5 mL of the extract were used for the DLLME. In the DLLME, the target analytes in the extraction solvent were rapidly extracted into a small volume of chloroform and analyzed by chromatography-mass spectrometry (GC-MS). The parameters affecting the DLLME, including type and volume of extraction and disperser solvents, salt effect and extraction time, were investigated and optimized. Under the optimum conditions, the enrichment factors (EFs) ranged from 140 to 208. The linear relationship was obtained in the range of 0.4–928 ng mL−1, which showed satisfactory linearity with correlation coefficients (r2) over 0.9989 for all the analytes. The limits of detection (LOD) were between 0.04 and 0.24 ng mL−1and the average recoveries were between 89.9 and 99.7% with relative standard deviations (RSDs) ranging from 2.5 to 6.7% in all cases. The method was successfully applied to the preconcentration and determination of these target compounds in tobacco additives.

Thin‐layer molecularly imprinted polymer (MIP) composite membranes for selective binding of monocrotophos (MCP) pesticide from aqueous solutions were developed. The procedure was based on commercially available membrane modules that were rinsed with prepolymerization imprinting mixtures. After the in situ polymerization and generation of MIP films on the membranes within the modules, the membranes were evaluated in terms of affinity toward the target molecule MCP. MIP membranes with different porogens and different monomers on Nylon‐6 membranes were prepared. It was shown that MIP membranes synthesized with methacrylic acid as monomer and toluene as porogens on the Nylon‐6 membranes provided a highly selective binding of MCP from aqueous solutions under the optimized elution conditions. With the novel surface modification technique, the low nonspecific binding properties of the microfiltration membrane could successfully be combined with the receptor properties of molecular imprints, yielding substance‐specific MIP composite membranes. The high affinity of these synthetic membranes to MCP pesticide together with their straightforward and inexpensive preparation could be applied in a fast preconcertration step, solid‐phase extraction, by a simple microfitration for the determination of MCP in water. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4468–4473, 2006

A novel extraction method, namely dynamic ultrasound‐assisted extraction, is investigated. This technique is efficient with respect to both time and solvent consumption because it utilizes ultrasonic energy in dynamic mode during extraction. Polyphenols (chlorogenic acid, esculetin, rutin, scopoletin, and quercitrin) are extracted from a tobacco (Nicotina tobaccum L.) sample for 10 min with 6 mL of solvent. Fresh solvent is continuously pumped through the sample, with which the analytes can be rapidly extracted, and the possibility of degradation efficiently avoided. Methanol involving 0.5% w/v ascorbic acid was used as extraction solvent; optimal flow rate and extraction time were investigated. The extract was cleaned up by C18 disposable cartridge. The spiked and nonspiked tobacco samples were used for the evaluation of the proposed method. Recoveries obtained were varied from 96 to 108% and RSDs from 2.0 to 4.6%. This extraction technique was revealed to recover larger amounts of polyphenols from tobacco, compared to the static ultrasound‐assisted extraction method.

Stressful life events (SLEs) are an important causal factor in depression; however, the mechanism by which SLEs cause depression remains unclear. Recent studies suggested that white matter (WM) microstructures might be a potential mediator between SLEs and depression. Hence, we aimed to investigate the concrete correspondence among them using mediation effect models.

To explore the genetic bias in a Chinese family suspected of having congenital nephrotic syndrome of the Finnish type (CNF).