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A challenge for slowly relaxing carbon monoxide (CO) molecules detection using photoacoustic spectroscopy (PAS) is to promote the vibration-translation (V-T) relaxation process. Addressing this challenge, a sensitivity enhanced photoacoustic CO sensor with sulfur hexafluoride (SF6) as the promotor is investigated and demonstrated. A 1568 nm near-infrared (NIR) laser diode and a customized optical amplifier are used as the excitation source to generate the photoacoustic signal. A differential photoacoustic cell is simulated and designed to obtain identical laminar flow distribution in the resonant cell to suppress the flow noise. The modulation frequency and added SF6 volume ratio are optimized experimentally to achieve optimal sensitivity. Feasibility and performance of the CO sensor with a small amount of SF6 as promotor is discussed and evaluated, obtaining a ~ 2 times improvement of signal value compared to the one with pure N2 background and resulting in a minimum detection limit of 467.5 ppb for CO detection.

Globo H is a tumor-associated carbohydrate antigen (TACA), which serves as a valuable target for antitumor vaccine or cancer immunotherapies. However, most TACAs are T-cell-independent, and they cannot induce powerful immune response due to their poor immunogenicity. To address this problem, herein, several Globo H analogues with modification on the N-acyl group were prepared through a preactivation-based glycosylation strategy from the non-reducing end to the reducing end. These modified Globo H derivatives were then conjugated with carrier protein CRM197 to form glycoconjugates as anticancer vaccine candidates, which were used in combination with adjuvant glycolipid C34 for immunological studies. The immunological effects of these synthetic vaccine candidates were evaluated on Balb/c mice. The results showed that the fluorine-modified N-acyl Globo H conjugates can induce higher titers of IgG antibodies that can recognize the naturally occurring Globo H antigen on the surface of cancer cells and can eliminate cancer cells in the presence of a complement, indicating the potential of these synthetic glycoconjugates as anticancer vaccine candidates.

A new glycosylation method promoted by visible light with 3,5-dimethoxyphenyl glycoside as the donor was developed. This protocol delivers both O-glycosides and N-glycosides in moderate to excellent yields using a wide range of O-nucleophiles and nucleobases as the glycosyl acceptors.

In Automatic Speech Recognition (ASR), transcribed data take substantial effort to obtain. It is worthwhile to explore how to selective the samples with more information from un-transcribed datapool to get a better model with the limited cost. Therefore, active learning in ASR becomes a research topic. In this manuscript, we proposed two new methods of active learning. One is Signal-Model Committee Approach (SMCA) and the other is LM-based Certainty Approach (LMCA). These two methods respectively evaluate the information amount of samples from different angles and can be applied together for joint sampling in some scenarios. We conducted many comparative experiments on Listen, Attend and Spell (LAS) model according to different demands. In experiments, we compared our approach with the random sampling and another state-of-the-art committee-based approach: heterogeneous neural networks (HNN) based approach. We examined our approach in CER in Chinese Mandarin speech recognition task. The results show that proposed approach is not only simple to use, but also has the best performance.

Submarine or sub-lacustrine lobe deposits are important reservoirs, but the fan fringe deposits form heterogeneities within deep water fan deposits. Fan fringe facies records the complex sediment gravity flow types. By understanding of the bed types and flow mechanisms, we can identify the fan fringe deposit, which aids in the reconstruction of deep water fan and reservoir evaluations. The Jiucaiyuanzi and Dalongkou sections in the West Bogda Mountains preserve well-exposed 536-m and 171-m thick successions, respectively, of a deep water lacustrine depositional system from the Middle Permian Lucaogou Formation. Bed types of the Lucaogou Formation include high-density turbidite, low-density turbidite, incomplete Bouma-type turbidite, hybrid event beds, and slump deposits. The Lucaogou Formation is interpreted here as a fan fringe facies due to the thin bed thickness that characterize turbidites and hybrid event beds, as well as the predominance of the isolated sheet architecture. Previous studies suggest that these deposits were considered as deposited in a deep water setting due to the absence of wave-related structures. The presence of abundant mud clasts in massive medium-coarse grained sandstone beds reflects the significant erosional capability and interactions between high-density turbidity currents and lake floor. The fan fringe facies here contains amalgamated and thick-bedded homolithic facies (~ 30%) and thin-bedded heterolithic facies (~ 70%). The examination of the bed type is of wider significance for facies prediction and reservoir heterogeneity in the sub-lacustrine fan fringe facies.

Antimicrobial resistance (AMR) is one of the significant global issues to public health. Compared to other aquatic environments, research on AMR in groundwater is scarce. In the study, a meta-analysis was conducted to explore the characteristics and risks of antibiotics and antibiotic resistance genes (ARGs) in global groundwater, using a data set of antibiotic concentrations collected from publications during 2000-2021 and a large-scale metagenomes of groundwater samples (n = 330). The ecotoxicological risks of antibiotics in the global groundwater were evaluated using mixture risk quotient with concentration addition model to consider the synergistic effects of multiple antibiotics. Bioinformatic annotations identified 1413 ARGs belonging to 37 ARG types in the global groundwater, dominated by rifamycin, polyketide, and quinolone resistance genes and including some emerging ARGs such as mcr-family and carbapenem genes. Relatively, the level of ARGs in the groundwater from spring was significantly higher (ANOVA, p0.01) than those from the riparian zone, sand and deep aquifer. Similarly, metal resistance genes (MRGs) were prevalent in the global groundwater, and network analysis suggested the MRGs presented non-random co-occurrence with the ARGs in such environments. Taxonomic annotations showed Proteobacteria, Actinobacteria, Eukaryota, Acidobacteria and Thaumarchaeota were the dominant phylum in the groundwater, and the microbial community largely shaped profile of ARGs in the environment. Notably, the ARGs presented co-occurrence with mobile genetic elements, virulence factors and human bacterial pathogens, indicating potential dissemination risk of ARGs in the groundwater. Furthermore, an omics-based approach was used for health risk assessment of antibiotic resistome and screened out 152 risk ARGs in the global groundwater. Comparatively, spring and cold creek presented higher risk index, which deserves more attention to ensure the safety of water supply.

The increasing instrumentation of physical and computing processes has given us unprecedented capabilities to collect massive volumes of time series. Power data is a typical kind of time series. Considering that the original time series data has ineluctable limitations such as uneven distribution, non-uniform length, poor sampling rate and noisy, we propose a learning=based similarity join for power data consisting of RNN encoder and matrix model. In addition, we develop the partition techniques by grouping process nodes following the matrix join model, ensuring the accuracy and efficiency of similarity join for data series. We conduct experiments on real data-set to evaluate the performance of our approach, demonstrating the effectiveness and scalability of our method.

Highly efficient emission has been a long-lasting pursuit for carbon dots (CDs) owing to their enormous potential in optoelectronic applications. Nevertheless, their room-temperature phosphorescence (RTP) performance still largely lags behind their outstanding fluorescence emission, especially in the blue spectral region. Herein, high-efficiency blue RTP CDs have been designed and constructed via a simple molecular engineering strategy, enabling CDs with an unprecedented phosphorescence quantum efficiency of to 50.17% and a long lifetime of 2.03 s. This treating route facilitates the formation of high-density (n, π*) configurations in the CD π-π conjugate system through the introduction of abundant functional groups, which can evoke a strong spin-orbit coupling and further promote the intersystem crossing from singlet to triplet excited states and radiative recombination from triplet excited states to ground state. With blue phosphorescent CDs as triplet donors, green, red, and white afterglow composites are successfully fabricated via effective phosphorescence Förster resonance energy transfer. Importantly, the color temperature of the white afterglow emission can be widely and facilely tuned from cool white to pure white and warm white. Moreover, advanced information encryption, light illumination, and afterglow/dynamic visual display have been demonstrated when using these multicolor-emitting CD-based afterglow systems.

Carbyne, as the truly one-dimensional carbon allotrope with sp-hybridization, has attracted significant interest in recent years, showing potential applications in next-generation molecular devices due to its ultimate one-atom thinness. Various excellent properties of carbyne have been predicted, however, free-standing carbyne sample is extremely unstable and the corresponding experimental researches and modifications are under-developed compared to other known carbon allotropes. The synthesis of carbyne has been slowly developed for the past decades. Recently, there have been several breakthroughs in in-situ synthesis and measurement of carbyne related materials, as well as the preparation of ultra-long carbon chains toward infinite carbyne. These progresses have aroused widespread discussion in the academic community. In this review, the latest approaches in the synthesis of sp carbon are summarized. We then discuss its extraordinary properties, including mechanical, electronic, magnetic, and optical properties, especially focusing on the regulations of these properties. Finally, we provide a perspective on the development of carbyne.

Carbohydrates play important roles in life science, but their synthesis is always hampered by their complicated chemical structures. Scientists have never stopped trying to solve the problem of glycan synthesis from various aspects. Here a brief overview of recent progress in glycan synthesis, including chemical approaches, chemoenzymatic approaches, and automated synthesis, will be discussed, focusing on the efficiency of new glycosylation methods, the stereoselectivity of coupled products, and their applications in the assembly of complex glycan chains.

The Keap1 (Kelch-like ECH-associated protein 1)-Nrf2 (nuclear factor erythroid 2-related factor 2)-ARE (antioxidant response element) pathway is the major defending mechanism against oxidative stresses, and directly disrupting the Keap1-Nrf2 protein-protein interaction (PPI) has been an attractive strategy to target oxidative stress-related diseases, including cardiovascular diseases. Here, we describe the design, synthesis, and structure-activity relationships (SARs) of indoline-based compounds as potent Keap1-Nrf2 PPI inhibitors. Comprehensive SAR analysis and thermodynamics-guided optimization identified 19a as the most potent inhibitor in this series, with an IC50 of 22 nM in a competitive fluorescence polarization assay. Further evaluation indicated the proper drug-like properties of 19a. Compound 19a dose-dependently upregulated genes and protein level of Nrf2 as well as its downstream markers and showed protective effects against lipopolysaccharide-induced injury in both H9c2 cardiac cells and mouse models. Collectively, we reported here a novel indoline-based Keap1-Nrf2 PPI inhibitor as a potential cardioprotective agent.

The photoinitiated intramolecular hydroetherification of alkenols has been used to form C-O bonds, but the intermolecular hydroetherification of alkenes with alcohols remains an unsolved challenge. We herein report the visible-light-promoted 2-deoxyglycosylation of alcohols with glycals. The glycosylation reaction was completed within 2 min in a high quantum yield (ϕ=28.6). This method was suitable for a wide array of substrates and displayed good reaction yields and excellent stereoselectivity. The value of this protocol was further demonstrated by the iterative synthesis of 2-deoxyglycans with α-2-deoxyglycosidic linkages up to a 20-mer in length and digoxin with β-2-deoxyglycosidic linkages. Mechanistic studies indicated that this reaction involved a glycosyl radical cation intermediate and a photoinitiated chain process.

Carbon dots (CDs), as one new class of carbon nanomaterials with various structure and extraordinary physicochemical properties, have attracted tremendous interest for their potential applications in tumor theranostics, especially in targeted bioimaging and therapy. In these areas, CDs and its derivatives have been employed as highly efficient imaging agent for photoluminescence bioimaging of tumors cells. With unique structure, optical and/or dose attention properties, CDs have been harnessed in various nanotheranostic strategies for diverse tumors through integrating with other functional nanoparticles or utilizing their inherent physical properties. Up to now, CDs have been approved as novel biomaterials by their excellent performances in precise targeted bioimaging and therapy for tumors. Herein, the latest progress in the development of CDs in targeted bioimaging and tumor therapy are reviewed. Meanwhile, the challenges and future prospects of the application of CDs in promising nanotheranostic strategies are discussed and proposed.

This article presents an experimentally validated electromechanical beam model for a representative cymbal-like piezocomposite active segment of a bioinspired piezocomposite aquatic propulsor/pump. The proposed concept is a self-contained propulsion/pumping system involving a series of piezoactive soft cymbal-like segments that are connected by passive soft connective segments. A series of phased excitations in expansion and contraction applied to active segments create a traveling wave along the axis of the pump, which in return propels the fluid. A parametric analysis is conducted using the proposed model to understand the effectiveness of the cymbal-like piezocomposite active segment as a function of critical structural parameters. Area change of the cymbal-like actuators, which is correlated to the propulsion power, is studied based on the analysis of the induced moment, curvature, and area change due to piezoelectric excitation. Objective functions and criteria are proposed and evaluated to understand the effectiveness, and to identify the optimal structural parameters of the piezocomposite pump. The influence of a sealant layer for waterproofing is also examined. Both bimorph and unimorph configurations are analyzed, and the results are compared.

Two-dimensional (2D) layered semiconductor materials have emerged as prospective channel materials in flexible thin-film field effect transistors (TFTs) recently because of their unique electrical ...

A novel transformation from rhamnose-type C-glycosides to 2-cyclopentenones is described. With the promotion of fluoroboric acid, C-glycosides underwent ring opening and subsequent Nazarov cyclization to afford 2-cyclopentenones in good to excellent yields. The solvent and the concentration of acid are crucial to the yield of this transformation.

We report a novel and highly stereoselective electro-2-deoxyglycosylation from glycals. This method features excellent stereoselectivity, scope, and functional-group tolerance. This process can also be applied to the modification of a wide range of natural products and drugs. Furthermore, a scalable synthesis of glycosylated podophyllotoxin and a one-pot trisaccharide synthesis through iterative electroglycosylations were achieved.

In order to further promote the optimization of the rural settlement pattern in the plateau and mountainous multi-ethnic gathering areas, and provide a basis for the protection and development of plateau mountainous ethnic settlements in the new period, the landscape pattern index method and ArcGIS spatial analysis method were used to quantitatively analyze the horizontal and vertical spatial distribution characteristics of rural settlements and their influencing factors in the multi-ethnic gathering area of the plateau and mountainous areas based on the 2017 remote sensing digital image data. The results show that: (1) The overall rural settlements in Longyang District on the horizontal space pattern show a small scale. The Han, Yi, Bai and Dai village settlements are mainly small settlements and small settlements. The Bai people are mainly medium-sized settlements. Their present the characteristics of cluster distribution. The Yi ethnic group has the highest degree of aggregation, and the Dai ethnic group has the lowest degree of aggregation. The spatial distribution and aggregation of different ethnic groups have significant differences in the level of spatial distribution. (2) Affected by geographical conditions on the vertical gradient, the settlements have a normal distribution overall, and the Bai settlements are the most obvious. (3) The spatial distribution characteristics of rural settlements in Longyang District are related to terrain, water system, transportation, and urban built-up areas, but there are certain differences between different ethnic groups. The optimization of the rural settlement pattern in the multi-ethnic gathering areas of the plateau and mountains should be based on different terrain conditions and different national cultures to suit local conditions, ensure ecological security, and promote national unity.

Prenatal stress (PNS) has a prolonged and adverse effect on offspring, leading to a significantly increased vulnerability to developing depression in their later life. Traditional therapies have delayed onset and limited efficacy; thus, it remains an urgent need to find novel medications with fast-onset and high-efficacy potentials. Crocin, with its structure clearly examined, has shown antidepressant-like effects. However, few studies extensively investigated its effect especially in mice exposed to PNS. Using an established PNS model, we tested whether crocin could have a rapid and persistent antidepressant-like effect in PNS mice. Growth hormone secretagogue receptor (GHSR) and phosphoinositide 3-kinase (PI3K) inhibitors were used to test their effects in antidepressant-like effect of crocin. Hippocampal GHSR-PI3K signaling was examined both in PNS mice treated with a single dose of crocin and in combination of GHSR inhibitor. PNS mice showed depression-like behaviors at juvenile and adulthood, and crocin induced an instant and persistent antidepressant-like response in PNS mice in a dose-dependent manner. Moreover, crocin increased the expression of hippocampal synaptic plasticity-associated proteins through the restoration of GHSR-PI3K signaling. Inhibitions of both GHSR and PI3K abolished the effect of crocin in alleviating depressive-like behaviors. More importantly, GHSR inhibitor JMV2959 blocked the enhanced expression of hippocampal plasticity-related proteins induced by crocin. The present study demonstrated that crocin induced a fast-onset and prolonged antidepressant effect in PNS mice and suggested that GHSR-PI3K signaling may play a key role in crocin's effect at least partially by a restoration of hippocampal synaptic plasticity-associated proteins.

Terminal α-2,6-sialylation of N-glycans is a humanized glycosylation that affects the properties and efficacy of therapeutic glycoproteins. Fc di-sialylation (a biantennary N-glycan with two α-2,6-linked sialic acids) of IgG antibodies imparts them with enhanced anti-inflammatory activity and other roles. However, the microheterogeneity of N-glycoforms presents a challenge for therapeutic development. Therefore, controlled sialylation has drawn considerable attention, but direct access to well-defined di-sialylated antibodies remains limited. Herein, a one-pot three-enzyme protocol was developed by engineering a bacterial sialyltransferase to facilitate the modification of therapeutic antibodies with N-acetylneuraminic acid or its derivatives towards optimized glycosylation. To overcome the low proficiency of bacterial sialyltransferase in antibody remodeling, the Photobacterium sp. JT-ISH-224 α-2,6-sialyltransferase (Psp2,6ST) was genetically engineered by terminal truncation and site-directed mutagenesis based on its protein crystal structure. With the optimized reaction conditions and using activity-based screening of various Psp2,6ST variants, a truncated mutant Psp2,6ST (111-511)-His6 A235M/A366G was shown to effectively improve the catalytic efficiency of antibody di-sialylation. Herceptin and the donor substrate promiscuity allow the introduction of bioorthogonal modifications of N-acetylneuraminic acid into antibodies for site-specific conjugation. 2-AB hydrophilic interaction chromatography analysis of the released N-glycans and intact mass characterization confirmed the high di-sialylation of Herceptin via the optimized one-pot three-enzyme reaction. This study established a versatile enzymatic approach for producing highly di-sialylated IgG antibodies. It provides new insights into engineering bacterial sialyltransferase for adaptation to the enzymatic glycoengineering of therapeutic antibodies and the glycosite-specific conjugation of antibodies.

The C-glycosylation of C-nucleophiles including allyltrimethylsilane, silyl enol ethers and phenols with N-(glycosyloxy)acetamides as glycosyl donors has been realized. This protocol provides a convenient and practical route for the synthesis of alkyl C-glycosides and aryl 2-deoxy-β-C-glycosides under mild reaction conditions.