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The carbon-carbon bond-forming cross-dehydrogenative coupling of alkenes and azlactones by organoselenium catalysis involving a high-valent

Hyperspectral image (HSI) has hundreds of continuous bands that contain a lot of redundant information. Besides, a spatial patch of a hyperspectral cube often contains some pixels different from the center pixel category, which are usually called interference pixels. The existence of such interference pixels has a negative effect on extracting more discriminative information. Therefore, in this letter, a multiattention fusion network (MAFN) for HSI classification is proposed. Compared with the current state-of-the-art methods, MAFN uses band attention module (BAM) and spatial attention module (SAM), respectively, to alleviate the influence of redundant bands and interfering pixels. In this way, MAFN realizes feature reuse and obtains complementary information from different levels by combining multiattention and multilevel fusion mechanisms, which can extract more representative features. Experiments were conducted on two public HSI data sets to demonstrate the effectiveness of MAFN. Our source code is available at https://github.com/Li-ZK/MAFN-2021.

The Cu2S/sulfite process achieves efficient iohexol abatement, in which reductive sulfur species prominently accelerate Cu species' redox cycle and radical generation.

An ultradurable conductive hydrogel is designed via radical polymerization of APBA and AM in the presence of XLG-stabilized CNTs. The hydrogel can monitor various human motions and exhibit vast potential in sensing and pro-healing of skin wounds.

The treatment of diabetic chronic wounds remains a global challenge due to the up-regulated inflammation response, oxidant stress, and persistent infection during healing process. Developing wound dressing materials with ideal biocompatibility, adequate mechanical strength, considerable under-water adhesion, sufficient anti-inflammation, antioxidant, and antibacterial properties is on-demand for clinical applications. In this study, we developed a bioactive skin-mimicking hydrogel band-aid through the combination of tannic acid (TA) and imidazolidinyl urea reinforced polyurethane (PMI) (TAP hydrogel) and explored its potentials in various medical applications, including hemostasis, normal skin incision, full-thickness skin wounds, and bacterial-infection skin incision on diabetic mice. TA was loaded into PMI hydrogel network to enhance the mechanical properties of TAP hydrogels through multiple non-covalent interactions (break strength: 0.28–0.64 MPa; elongation at break: 650–930%), which could resist the local stress and maintain the structural integrity of wound dressings during applications. Moreover, owing to the promising moisture-resistant adhesiveness and organ hemostasis, outstanding anti-inflammation, antibacterial, and antioxidant properties, TAP hydrogels could efficiently promote the recovery of skin incision and defects on diabetic mice. To further simulate the practical situation and explore the potential in clinical application, we also verified the treatment efficiency of TAP hydrogel in S. aureus-infected skin incision model on diabetic mice., Graphical abstract Image 1, Highlights • Bioactive skin-mimicking hydrogels were developed through the combination of tannic acid and polyurethane. • The wound healing and infected skin incision closure by the bioactive skin-mimicking hydrogels were studied on diabetic mice.

P-chirogenic compounds have been applied in different fields, especially in asymmetric catalysis as ligands and organocatalysts. However, broader applicability has been severely restricted by the l...

Infantile spasms (IS) is a typical childhood epileptic disorder with generalized seizures. The sudden, frequent and complex characteristics of infantile spasms are the main causes of sudden death, severe comorbidities and other adverse consequences. Effective prediction is highly critical to infantile spasms subjects, but few related studies have been done in the past. To address this, this study proposes a seizure prediction framework for infantile spasms by combining the statistical analysis and deep learning model. The analysis is conducted on dividing the continuous scalp electroencephalograms (sEEG) into 5 phases: Interictal, Preictal, Seizure Prediction Horizon (SPH), Seizure, and Postictal. The brain network of Phase-Locking Value (PLV) of 5 typical brain rhythms is constructed, and the mechanism of epileptic changes is analyzed by statistical methods. It is found that 1) the connections between the prefrontal, occipital, and central regions show a large variability at each stage of seizure transition, and 2) 4 sub-bands of brain rhythms (θ, α, β, γ) are predominant. Group and individual variabilities are validated by using the Resnet18 deep model on data from 25 patients with infantile spasms, where the consistent results to statistical analyses can be observed. The optimized model achieves an average of 79.78 %, 94.46%, 75.46% accuracy, specificity, and recall rate, respectively. The method accomplishes the analysis of the synergy between infantile spasms mechanism, model, data and algorithm, providing a guideline to build an intelligent and systematic model for comprehensive IS seizure prediction.

A new strategy for the construction of chiral sulfides by catalytic enantioselective hydrothiolation of alkenes via an electrophilic pathway has been developed. Using this strategy, cyclic and acyclic unactivated alkenes efficiently afforded various chiral products in the presence of electrophilic sulfur reagents and silanes through chiral chalcogenide catalysis. The obtained products were easily transformed into other types of valuable chiral sulfur-containing compounds. Mechanistic studies revealed that the superior construction of chiral thiiranium ion intermediate is the key to achieving such a transformation.

Objective: To demonstrate differences in cardiovascular structure and function between diabetic and non-diabetic older adults. To investigate associations between acyl-carnitines and cardiovascular function as indexed by imaging measurements. Methods: A community-based cohort of older adults without cardiovascular disease underwent current cardiovascular imaging and metabolomics acyl-carnitines profiling based on current and archived sera obtained fifteen years prior to examination. Results: A total of 933 participants (women 56%, n=521) with a mean age 63±13 years were studied. Old diabetics compared to old non-diabetics had lower myocardial relaxation (0.8±0.2 vs 0.9±0.3, p=0.0039); lower left atrial conduit strain (12±4.3 vs 14±4.1, p=0.045), lower left atrial conduit strain rate (-1.2±0.4 vs -1.3±0.5, p=0.042) and lower ratio of left atrial conduit strain to left atrial booster strain (0.5±0.2 vs 0.7±0.3, p=0.0029). Higher levels of archived short chain acyl-carnitine were associated with present-day impairments in myocardial relaxation (C5:1; OR 1.03, p=0.011), worse left atrial conduit strain function (C5:1; OR 1.03, p=0.037). Increases in hydroxylated acyl-carnitines were associated with worse left atrial conduit strain [(C4-OH; OR 1.05, p=0.0017), (C16:2-OH; OR 1.18, p=0.037)]. Current, archived and changes in long chain acyl-carnitines were associated with cardiovascular functions [(C16; OR 1.02, p=0.002), (C20:3; OR 1.01, p=0.014), (C14:3; OR 1.12, p=0.033), (C18:1; OR 1.01, p=0.018), (C18:2; OR 1.01, p=0.028), (C20:4; OR 1.10, p=0.038)] (all p

Organoselenium catalysis has attracted increasing interest in recent years. This Cluster highlights recent key advances in this area regarding the functionalization of alkenes, alkynes, and arenes by electrophilic selenium catalysis, selenonium salt catalysis, selenium-based chalcogen-bonding catalysis, and Lewis basic selenium catalysis. These achievements might inspire and help future research.1 Introduction2 Electrophilic Selenium Catalysis3 Selenonium Salt Catalysis4 Selenium-Based Chalcogen-Bond Catalysis5 Lewis Basic Selenide Catalysis6 Conclusion

Selenium catalysis has become an exciting area in organic synthesis. In various selenium-catalyzed reactions, different substrates have been utilized. However, alkynes as substrates have received m...

Enantioselective electrophilic three-component thioarylation of alkenes by chiral selenide catalysis with free phenols as arylating sources is disclosed. A variety of chiral phenols were achieved i...

Noncovalent cross-linked hydrogels with promising mechanical properties are on demand for applications in tissue engineering, flexible electronics, and actuators. However, integrating excellent mechanical properties with facile preparation for the design of hydrogen bond cross-linked hydrogels is still challenging. In this work, an advanced hydrogel was prepared from acrylamide and N-acryloyl phenylalanine by one-pot free-radical copolymerization. Owing to hydrophobicity-assisted multiple hydrogen bonding interactions among phenylalanine derivatives, the hydrogels exhibited fascinating mechanical behaviors: tensile strength of 0.35 MPa, elongation at break of 2100%, tearing energy of 1134 J/m2, and compression strength of 3.56 MPa. The hydrogels also showed robust elasticity and fatigue resistance, and the compression strength did not show any decline, even after 100 successive cycles, as well as promising self-recovery property. In addition, the cytotoxicity test in vitro proved that the hydrogel showed good biocompatibility with normal human liver cells (LO2 cells). The excellent stretchability, robust elasticity, high toughness, fatigue resistance, and biocompatibility of the hydrogel demonstrated its vast potential in the biomedical field and flexible electronic devices.

Recently, iron-based heterogenous catalysts have received much attention in the activation of peracetic acid (PAA) for generating reactive radicals to degrade organic pollutants, yet the PAA activation efficiency is compromised by the slow transformation from Fe(III) to Fe(II). Herein, considering the electron-donating ability of reducing sulfur species, a novel advanced oxidation process by combining pyrite and PAA (simplified as pyrite/PAA) for the abatement of tetracycline (TC) is proposed in this study. In the pyrite/PAA process, TC can be completely removed within 30 min under neutral conditions by the synergy of homogeneous and heterogenous Fe(II) species. CH

Salmonella enterica serovar Typhimurium is a leading cause of gastroenteritis worldwide and a deadly pathogen in children, immunocompromised patients, and the elderly. Salmonella induces innate immune responses through the Nlrc4 inflammasome, which has been demonstrated to have distinct roles during systemic and mucosal detection of flagellin and non-flagellin molecules. We hypothesized that Nlrc4 recognition of Salmonella flagellin is the dominant protective pathway during infection. To test this hypothesis, we used wild-type, flagellin-deficient, and flagellin-overproducing Salmonella to establish the role of flagellin in mediating Nlrc4-dependent host resistance during systemic and mucosal infection. We observed that during the systemic phase of infection, Salmonella efficiently evades Nlrc4-mediated innate immunity. However, during mucosal Salmonella infection, flagellin recognition by the Nlrc4 inflammasome pathway is the dominant mediator of protective innate immunity. These data establish that recognition of Salmonella’s flagellin by the Nlrc4 inflammasome during mucosal infection is the dominant innate protective pathway for host resistance against the enteric pathogen.

Thio- and halodifluoromethylated compounds are an important class of compounds in medicinal chemistry and organic synthesis. Herein, we report a facile method for the construction of these compound...

Background Left atrial (LA) dysfunction is associated with morbidity and mortality. To the knowledge of the authors, the relationship of LA strain to long-term prognosis in participants with ST-segment elevation myocardial infarction (STEMI) is unknown. Purpose To evaluate LA strain as a long-term outcome predictor in STEMI in a prospective, multicenter cardiac MRI cohort. Materials and Methods Participants with STEMI who underwent primary percutaneous coronary intervention and cardiac MRI from 10 sites (EARLY-MYO-CMR registry, clinical trial number NCT03768453) were included. The parent study took place between August 2013 and December 2018. LA longitudinal strain and strain rate parameters were derived from cine cardiac MRI by using an in-house semiautomated method. Major adverse cardiac events (MACEs) were defined as cardiovascular death, myocardial reinfarction, hospitalization for heart failure, and stroke. The association between LA performance and MACE was evaluated by using time-dependent receiver operating characteristic analysis, Kaplan-Meier analysis, and multivariable Cox regression analysis. Results A total of 321 participants (median age, 59 years; age range, 27-75 years; 90% men) were included in this study. During median follow-up of 3.7 years, MACE occurred in 76 participants (23.7%). Participants with impaired reservoir (≤22%) and conduit strain (≤10%) had a higher risk of MACE than those with reservoir strain greater than 22% and conduit strain greater than 10% (P < .001). Reservoir strain (hazard ratio, 0.84; 95% confidence interval: 0.77, 0.91; P < .001) and conduit strain (hazard ratio, 0.81; 95% confidence interval: 0.73, 0.89; P < .001) were independent predictors for MACE after adjustment for known risk factors. Finally, LA reservoir and conduit strains provided incremental prognostic value over traditional outcome predictors (Uno C statistic comparing models, 0.75 vs 0.68; P = .04). Conclusion Assessment of left atrial strain, as a measure of left atrial function, provided incremental prognostic information to established predictors in ST-segment elevation myocardial infarction. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Kawel-Boehm and Bremerich in this issue.

An unprecedented approach for efficient synthesis of functionalized allylic gem-difluorides via catalytic fluorinative Meyer-Schuster-like rearrangement is disclosed. This transformation proceeded with readily accessible propargylic fluorides, and low-cost B-F reagents and electrophilic reagents by sulfide catalysis. A series of iodinated, brominated, and trifluoromethylthiolated allylic gem-difluorides that were difficult to access by other methods were facilely produced with a wide range of functional groups. Importantly, the obtained iodinated products could be incorporated into different drugs and natural products, and could be expediently converted into many other valuable gem-difluoroalkyl molecules as well. Mechanistic studies revealed that this reaction went through a regioselective fluorination of alkynes followed by a formal 1,3-fluorine migration under the assistance of the B-F reagents to give the desired products.

Curvature-based three-dimensional cardiovascular magnetic resonance (CMR) allows regional function characterization without an external spatial frame of reference. However, introduction of this modality into clinical practice is hampered by lack of reference values. We aim to establish normal ranges for 3D left ventricular (LV) regional parameters in relation to age and gender for 171 healthy subjects. LV geometrical reconstruction and automatic calculation of regional parameters were implemented by in-house software (CardioWerkz) using stacks of short-axis cine slices. Parameter normal ranges were stratified by gender and age categories (≤44, 45–64, 65–74 and 75–84 years). Our software had excellent intra- and inter-observer agreement. Ageing was significantly associated with increases in end-systolic (ES) curvedness (CES) and area strain (AS) with higher rates of increase in males, end-diastolic (ED) and ES wall thickness (WTED, WTES) with higher rates of increase in females, and reductions in ED and ES wall stress indices (σi,ED) with higher rates of increase in females. Females exhibited greater ED curvedness, CES, σi,ED and AS than males, but smaller WTED and WTES. Age × gender interaction was not observed for any parameter. This study establishes age and gender specific reference values for 3D LV regional parameters using CMR without additional image acquisition.

In some cardiac pathologies, impairment of left ventricular (LV) longitudinal function may precede reduction in LV ejection fraction. This study investigates the effectiveness of a fast method to quantify long-axis LV function compared to conventional feature tracking and manual approaches. The study consisted of 50 normal controls and 100 heart failure (HF) patients including 40 with reduced ejection fraction (HFrEF), 30 with mid-range ejection fraction (HFmrEF), and 30 with preserved ejection fraction (HFpEF). Parameters including fast long-axis strain (FLAS) at end-systole and peak strain rates during systole (FLASRs), early diastole (FLASRe), and atrial contraction (FLASRa) were derived by a fast semi-automated approach on cine cardiovascular magnetic resonance. FLAS exhibited good agreement with strain values obtained using conventional feature tracking (bias − 2.9%, limits of agreement ± 3.0%) and the manual approach (bias 0.6%, limits of agreement ± 2.1%), where FLAS was more reproducible and required shorter measurement time. The mean FLAS (HFrEF < HFmrEF < HFpEF < controls; 6.1 ± 2.4

Purpose: To evaluate the efficacy of the semiquantitative and quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating between benign and malignant soft-tissue tumors. Methods: A total of 45 patients with pathologically confirmed soft-tissue tumors (15 benign and 30 malignant tumors) underwent DCE-MRI. The semiquantitative parameters assessed were as follows: time to peak (TTP), maximum concentration (MAX Conc), area under the curve of time-concentration curve (AUC-TC), and maximum rise slope (MAX Slope). Quantitative DCE-MRI was analyzed with the extended Tofts-Kety model to assess the following quantitative parameters: volume transfer constant (Ktrans), microvascular permeability reflux constant (Kep), and distribute volume per unit tissue volume (Ve). Data were evaluated using the independent t test or Mann-Whitney U test and receiver operating characteristic (ROC) curves. Results: The TTP ( P = .0035), MAX Conc ( P = .0018), AUC-TC ( P = .0018), MAX Slope ( P = .0018), Ktrans ( P = .0018), and Kep ( P = .0035) were significantly different between the benign and malignant soft-tissue tumors. The AUC of the ROC curve demonstrated the diagnostic potential of TTP (0.778), MAX Conc (0.849), AUC-TC (0.831), MAX Slope (0.847), Ktrans (0.836), Kep (0.778), and Ve (0.638). Conclusions: The use of semiquantitative and quantitative parameters of DCE-MRI enabled differentiation between benign and malignant soft-tissue tumors. The values of TTP were lower, while those of MAX Conc, AUC-TC, MAX Slope, Ktrans, and Kep were higher in malignant than in benign tumors.

Nitrogen/phosphorus-doped carbon dots (N, P-CDs) with a quantum yield as high as 76.5% were synthesized by carbonizing maize starch via a facile ethanol solvothermal approach. Transmission electron microscopy (TEM) measurement shows that the as-prepared N, P-CDs displayed a quasi-spherical shape with a mean size of ca. 2.5 nm. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy disclosed the presence of –OH, –NH2, –COOH, and –CO functional groups over the surface of N, P-CDs. On the basis of excellent fluorescent properties with strong blue fluorescence emission at 445 nm upon excitation at 340 nm, these N, P-CDs were adopted as a fluorescent probe towards the effective detection of Fe3+ ions in water. The limit of detection (LOD) was as low as 0.1 μmol L−1 and showed a better linear relationship in the range of 0.1 ∼ 50 μmol L−1. In conclusion, these synthesized N, P-CDs can be efficiently used as a promising candidate for the detection of Fe3+ ions in some practical samples.

With the development of the city and the increase of the population, the demand for transportation is increasing. The increases in transportation ways and demand have also brought certain energy and environmental problems to transportation construction. A good transportation environment and green travel experience have an important role in promoting the happiness of urban life and the sustainable development of society. Based on this, the following solutions are proposed for the construction and development of urban green transportation. First, as a guiding role, the government should formulate active transportation and green transportation policies to promote the reform of multiple public transportation methods. Second, as a leading role, the market can support a variety of the construction of green travel modes, which could encourage the development of shared bicycles and new energy vehicles. Third, as the main role of city, the citizens would like to choose green travel tools with the guidance in the conscious level. If we built green behavior into a fashionable business card of the city, green behavior will lead the city’s transportation construction and development.

Salvia miltiorrhiza, known as danshen, is one of most valued medicinal plants in China. Although it has been cultivated since ancient times, an optimal culture system needs to be standardized for this important species. Here, we explored the phytochemical properties of S. miltiorrhiza with the treatments of rare earth elements (REEs) to develop an optimal tissue culture system. Four-week-old in vitro-grown S. miltiorrhiza plantlets were used as explants. The experiment was conducted in a randomized block design on a Murashige and Skoog (MS) medium containing 0.2 mg·L−1 naphthaleneacetic acid (NAA) to induce rooting at four different concentrations (50, 100, 200, and 300 μM) of REEs such as cerium (Ce), lanthanum (La), or praseodymium (Pr), respectively. Compared with all REEs at different concentrations, 100 μM Pr induced greater root length than Ce or La at any concentrations. Concomitantly, 0.38 μg tanshinone IIA/mg dry weight (DW) was observed, which was 54.84% higher than in the control. Similarly, chlorophyll content, antioxidant enzyme activity, and secondary metabolite were enhanced in rooting medium supplemented with 100 μM Pr. Therefore, this study showed that 100 μM Pr is an adequate concentration in the optimal culture system for promoting plant growth as well as enhancing secondary metabolite content in S. miltiorrhiza.

A series of water-soluble cationic thienoviologen derivative photosensitizers (nTPy-Rs) for photodynamic therapy (PDT) is reported. Cationic pyridine groups were introduced into the thiophene framework to enhance solubility and bacteria-binding ability, which effectively improved bacteriological imaging and antibacterial activity. The optoelectronic properties of nTPy-Rs were regulated by adjusting the number of thiophene groups, and the differences in antibacterial activity due to the functional scaffolds were compared. The results showed that nTPy-Rs could generate reactive oxygen species (ROS, including macroscopic free radicals), efficiently inhibit bacterial growth, and achieve the minimum inhibitory concentration (MIC) to the ng mL

Jian Wang,1,2 Xiaodan Zhao,3 Guichang Tian,2 Xiaochao Liu,2 Chengyan Gui,2 Lin Xu1,4 1School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, People’s Republic of China; 2Department of Orthopedics, Qufu Hospital of TCM, Qufu, 273100, People’s Republic of China; 3Image Center, Shandong Provincial Third Hospital, Jinan, 250000, People’s Republic of China; 4Department of Orthopedics, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, 264100, People’s Republic of ChinaCorrespondence: Lin Xu, Department of Orthopedics, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, 264100, People’s Republic of China, Tel +86-13805350031, Email yantaixulin@163.com; yantaixulin@126.comObjective: To study the role of miR-138 on the repair of diabetic foot ulcer (DFU) and further to explore its possible mechanism.Materials and Methods: miR-138 inhibitor, IGF-1, LY294002 were used in DFU rat mode, and the mRNA expression of miR-138 was detected. HE staining was used to observe the histological changes of skin ulcer in rats. The level of inflammation, wound healing, and blood vessel formation-related factors were detected by ELISA and immunohistochemical. The expression of VEGF and PI3K/AKT pathway-related proteins were detected by Western blot. To further determine the underlying mechanism of miR-138 in the repair of DFU, telomerase inhibitor BIBR-1232 was used in HUVECs. Dual-luciferase assay was used to determine the target relationship between miR-138 and hTERT. CCK-8, transwell, and tube formation assays were conducted to observe the biological behavior of HUVECs. Inflammatory cytokines and PI3K/AKT pathway-related proteins were also measured by ELISA and Western blot.Results: The mRNA expression of miR-138 in DFU rat was increased and ulcer of diabetic foot rats was improved after silencing miR-138. The results of cellular bioactivity in vitro experiment were consistent with that in vivo. Meanwhile, after silencing miR-138, the level of inflammatory cytokines was decreased, while the level of anti-inflammatory and healing factors was increased in vivo and vitro. Moreover, the ratios of p-PI3K/PI3K and p-AKT/AKT were upregulated after treated with miR-138 inhibitor and miR-138 was negatively regulated the expression of hTERT. However, the inhibitory effect on inflammatory response and the promotion effect on wound healing of miR-138 inhibitor were reversed by LY294002 and BIBR-1232.Conclusion: Down-regulation of miR-138 could alleviate inflammatory response and promote wound healing in DFU rats by activating PI3K/AKT pathway and hTERT.Keywords: miR-138, diabetic foot ulcer, inflammatory response, wound healing, PI3K/AKT pathway, hTERT

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Development of biocompatible hydrogel adhesives with robust tissue adhesion to realize instant hemorrhage control and injury sealing, especially for emergency rescue and tissue repair, is still challenging. Herein, we report a potent hydrogel adhesive by free radical polymerization of