Search

Dendronized polymers (DPs) consist of a linear polymeric backbone with dendritic side chains. Fine-tuning of the functional groups in the side chains enriches the structural versatility of the DPs and imparts a variety of novel physical properties. Herein, the first on-surface synthesis of DPs is achieved via the postfunctionalization of polymers on Au(111), in which the surface-confinement-induced planar conformation and chiral configurations were unambiguously characterized. While the dendronized monomer was synthesized

In digital online advertising, advertisers procure ad impressions simultaneously on multiple platforms, or so-called channels, such as Google Ads, Meta Ads Manager, etc., each of which consists of numerous ad auctions. We study how an advertiser maximizes total conversion (e.g. ad clicks) while satisfying aggregate return-on-investment (ROI) and budget constraints across all channels. In practice, an advertiser does not have control over, and thus cannot globally optimize, which individual ad auctions she participates in for each channel, and instead authorizes a channel to procure impressions on her behalf: the advertiser can only utilize two levers on each channel, namely setting a per-channel budget and per-channel target ROI. In this work, we first analyze the effectiveness of each of these levers for solving the advertiser's global multi-channel problem. We show that when an advertiser only optimizes over per-channel ROIs, her total conversion can be arbitrarily worse than what she could have obtained in the global problem. Further, we show that the advertiser can achieve the global optimal conversion when she only optimizes over per-channel budgets. In light of this finding, under a bandit feedback setting that mimics real-world scenarios where advertisers have limited information on ad auctions in each channels and how channels procure ads, we present an efficient learning algorithm that produces per-channel budgets whose resulting conversion approximates that of the global optimal problem. Finally, we argue that all our results hold for both single-item and multi-item auctions from which channels procure impressions on advertisers' behalf.

This is a retrospective case–control study to ascertain the factors influencing nosocomial infection (NI) in elderly patients with hip fractures. A total of 80,174 patients (≥ 60 years) who suffered hip fractures between 2006 and 2017 were identified through a national inquiry of 94 hospitals. The patients were divided into an NI group and control group according to the occurrence or lack of occurrence of NI within 48 hours after surgery, respectively. Age, gender, hip fracture pattern, whether to operate, surgical treatments, and comorbidities were recorded as variables. A total of 9806 elderly hip fracture patients (60 years) were included, 1977 of whom were patients diagnosed with NI. The control group consisted of randomly drawn cases from the 9806 patients from different hospitals with a rate of one NI patient: four patients without NI. Patient gender, age, and in particular the number of comorbidities were associated with occurrence of NI. Using regression models to predict infection outcomes based on the number of comorbidities had an area under the curve (AUC) of 0.714, while using the Charlson comorbidity index (CCI) yielded a smaller value of 0.694. The most common comorbidities of this elderly cohort were chronic respiratory disease, hypertension, diabetes mellitus, cerebrovascular disease, and coronary heart disease. Older age, male gender, and greater number of comorbidities were found to be associated with the occurrence of NI. In particular, the number of comorbidities was the most accurate predictor of NI occurrence, and when used to build a regression model, it had greater predictive capability than CCI to predict NI in elderly hip fracture patients. Additionally, the common diseases of the elderly should be primarily considered when investigating the relationship between comorbidities and NI in older patients.

The direct C-H activation without directing groups can realize the para-selectivity, which is a powerful and concise approach for functionalization of arenes. Utilizing the strategy, a C5-olefination of methyleneindolinones has been successfully developed by palladium-catalyzed direct C-H activation, which provides an expeditious access to 5-vinylindolin-2-ones with high regioselectivity. The protocol is distinguished by a mild reaction system avoiding ligand and high temperature. The kinetic isotope experiments indicate that the C-H bond cleavage is the rate-limiting step.

Although post-functionalization is extensively used to introduce diverse functional groups into supramolecular polymers (SPs) in solution, post-functionalization of SPs on surfaces still remains unexplored. Here we achieved the on-surface post-functionalization of two SPs derived from 5,10,15-tri-(4-pyridyl)-20-bromophenyl porphyrin (Br-TPyP) via cross-coupling reactions on Au(111). The ladder-shaped, Cu-coordinated SPs preformed from Br-TPyP were functionalized through Heck reaction with 4-vinyl-1,1'-biphenyl. In the absence of Cu, Br-TPyP formed chiral SPs as two enantiomers via self-assembly, which were functionalized via divergent cross-coupling reaction with 4-isocyano-1,1'-biphenyl (ICBP). Surprisingly, this reaction was discovered as an enantioselective on-surface reaction induced by the chirality of SPs. Mechanistic analysis and DFT calculations indicated that after debromination of Br-TPyP and the first addition of ICBP, only one attack direction of ICBP to the chiral SP intermediate is permissive in the second addition step due to the steric hindrance, which guaranteed the high enantioselectivity of the reaction.

It has been documented that processing L2 and L1 engages a very similar brain network in bilingual adults. However, it is not known whether this similarity is evident in bilingual children as well or it develops with learning from children to adults. In the current study, we compared brain activation in Chinese-English bilingual children and adults during L1 and L2 processing. We found greater similarity between L1 and L2 in adults than in children, supporting the convergence hypothesis which argues that when the proficiency of L2 increases, the L2’s brain network converges to the L1’s brain network. We also found greater differences between adults and children in the brain for L2 processing than L1 processing, even though there were comparable increase in proficiency from children to adults in L1 and L2. It suggests an elongated developmental course for L2. This study provides important insights about developmental changes in the bilingual brain.

Aiming at the problems of brightness attenuation and contrast reduction in the target image caused by underwater low-visibility environments, a metal target detection method based on split-focus plane polarization imaging is proposed. Firstly, a hybrid enhancement method is proposed to clarify the degraded polarization image. In this study, the GrayWorld method is improved to compensate the attenuation difference of the total light intensity of the polarization image. Variational contrast and saturation enhancement algorithms are used to reduce the underwater scattering effect; secondly, a split-focus plane polarization imaging system is built to complete the control of camera parameters, polarization image acquisition and information processing. Under different underwater low-visibility conditions, polarization imaging of targets with different materials can be realized; finally, an image quality evaluation system is constructed to compare the light intensity and degree of polarization images that are collected by the focal plane polarization imaging system. The polarization characteristics of metal and nonmetal target plates are analyzed. The results show that under the condition of low visibility, the obtained polarization image contrast of the metal target is relatively high, and its EME, information entropy and average gradient are increased by 183.82%, 53.46% and 586.22% on average relative to the image of light intensity. In an underwater low-visibility scene, the method of focal plane polarization imaging proposed in this paper can reduce the difficulty of metal target detection.

Involucrella lithophila from the limestone area of Guangxi, China, is described and illustrated here. It is most similar to Hedyotis kurzii and Involucrella chereevensis in having tetragonal stems, slender pedicels and loculicidally dehiscent capsules, but it differs from the former by its 3–5 (–7)-lobed stipules, heterostylous and white flowers and depressed seeds, and from the latter by its 2–4 secondary leaf veins and heterostylous flowers. The molecular phylogenetic analysis revealed that this new species was embedded in the Involucrella clade and closely related to I. chereevensis. It is evaluated as Least Concern according to IUCN Red List Categories and Criteria.

In order to reveal the shale oil production mechanism and production efficiency under the energy-depleted development mode, experiments on expulsion oil based on imbibition and elastic energy release under high temperature and pressure were carried out, and nuclear magnetic resonance on-line monitoring was used to observe the production characteristics of shale oil. The experimental results show that the imbibition-expulsion oil mainly occurs in the small-size pore-throat system. Under the condition of high temperature and pressure, the oil-expulsion efficiency is generally less than 2% affected by pore pressure, which is significantly different from the conventional imbibition experiment results. Although elastic-energy expulsion oil occurs in different sizes of pore-throat systems, the oil-expulsion efficiency in large size pore-throat systems is more sensitive to temperature. Overall, the total elastic-energy oil-expulsion efficiency is significantly positively correlated with reservoir physical properties, production differential pressure and temperature, and negatively correlated with crude oil viscosity. Comprehensively considering various geological factors affecting oil-expulsion efficiency, the shale oil production efficiency evaluation model under the energy-depleted development mode is constructed, and the movable oil porosity of shale oil development section in the study area is evaluated. The results show that there is a good positive correlation between movable oil porosity and oil production intensity. The movable oil porosity of dry layer is generally lower than 0.5% and that of poor oil layer is between 0.5% and 1.5%. When the movable oil porosity is between 1.5 and 2.5%, it can be determined as the type II oil layer, and for more than 2.5%, it is the type I oil layer. The single-well evaluation results show that the shale oil “sweet spots” of the Lucaogou Formation in Jimsar Sag are mainly distributed in P2l22−1∼ P2l22−3 and P2l12−1∼ P2l12−3, which is in good agreement with the current development status.

[3]Radialenes are the smallest carbocyclic structures with unusual topologies and cross-conjugated π-electronic structures. Here, we report a novel [1+1+1] cycloaddition reaction for the synthesis of aza[3]radialenes on the Ag(111) surface, where the steric hindrance of the chlorine substituents guides the selective and orientational assembling of the isocyanide precursors. By combining scanning tunneling microscopy, non-contact atomic force microscopy, and time-of-flight secondary ion mass spectrometry, we determined the atomic structure of the produced aza[3]radialenes. Furthermore, two reaction pathways including synergistic and stepwise are proposed based on density functional theory calculations, which reveal the role of the chlorine substituents in the activation of the isocyano groups via electrostatic interaction.

Transarterial radioembolization (TARE) is an emerging treatment for patients with unresectable hepatocellular carcinoma (HCC). This study successfully developed radiometal-labeled chitosan microspheres (111In/177Lu-DTPA-CMS) with a diameter of 36.5 ± 5.3 μm for TARE. The radiochemical yields of 111In/177Lu-DTPA-CMS were greater than 90% with high radiochemical purities (>98%). Most of the 111In/177Lu-DTPA-CMS were retained in the hepatoma and liver at 1 h after intraarterial (i.a.) administration. Except for liver accumulation, radioactivity in each normal organ was less than 1% of the injected radioactivity (%IA) at 72 h after injection. At 10 days after injection of 177Lu-DTPA-CMS (18.6 ± 1.3 MBq), the size of the hepatoma was significantly reduced by around 81%, while that of the rats in the control group continued to grow. This study demonstrated the effectiveness of 177Lu-DTPA-CMS in the treatment of N1-S1 hepatoma. 111In/177Lu-DTPA-CMS have the potential to be a superior theranostic pair for the treatment of clinical hepatoma.

Additional file 1: Table S1. Summary of the main genetic studies reported on human head and body lice. Table S2. Species of head lice and body lice included in mt cytb gene phylogenetic analysis.

Additional file 1: Table S1. Relative abundance of microflora at the genus level of the five sampled ticks. Table S2. Relative abundance of the bacterial species of the five tick samples with the exception of the 35 most abundant species.

Quantum spins, referred to the spin operator preserved by full SU(2) symmetry in the absence of the magnetic anistropy, have been proposed to host exotic interactions with superconductivity4. However, spin orbit coupling and crystal field splitting normally cause a significant magnetic anisotropy for d/f-shell spins on surfaces6,9, breaking SU(2) symmetry and fabricating the spins with Ising properties10. Recently, magnetic nanographenes have been proven to host intrinsic quantum magnetism due to their negligible spin orbital coupling and crystal field splitting. Here, we fabricate three atomically precise nanographenes with the same magnetic ground state of spin S=1/2 on Pb(111) through engineering sublattice imbalance in graphene honeycomb lattice. Scanning tunneling spectroscopy reveals the coexistence of magnetic bound states and Kondo screening in such hybridized system. Through engineering the magnetic exchange strength between the unpaired spin in nanographenes and cooper pairs, quantum phase transition from the singlet to the doublet state has been observed, in consistent with quantum models of spins on superconductors. Our work demonstrates delocalized graphene magnetism host highly tunable magnetic bound states with cooper pairs, which can be further developed to study the Majorana bound states and other rich quantum physics of low-dimensional quantum spins on superconductors., Comment: 13 pages, 4figures

The increasing availability of real-time data has fueled the prevalence of algorithmic bidding (or autobidding) in online advertising markets, and has enabled online ad platforms to produce signals through machine learning techniques (i.e., ML advice) on advertisers' true perceived values for ad conversions. Previous works have studied the auction design problem while incorporating ML advice through various forms to improve total welfare of advertisers. Yet, such improvements could come at the cost of individual bidders' welfare, consequently eroding fairness of the ad platform. Motivated by this, we study how ad platforms can utilize ML advice to improve welfare guarantees and fairness on the individual bidder level in the autobidding world. We focus on a practical setting where ML advice takes the form of lower confidence bounds (or confidence intervals). We motivate a simple approach that directly sets such advice as personalized reserve prices when the platform consists of value-maximizing autobidders who are subject to return-on-ad spent (ROAS) constraints competing in multiple parallel auctions. Under parallel VCG auctions with ML advice-based reserves, we present a worst-case welfare lower-bound guarantee for individual agents, and show that platform fairness is positively correlated with ML advice quality. We also present an instance that demonstrates our welfare guarantee is tight. Further, we prove an impossibility result showing that no truthful, and possibly randomized mechanism with anonymous allocations and ML advice as personalized reserves can achieve universally better fairness guarantees than VCG when coupled with ML advice of the same quality. Finally, we extend our fairness guarantees with ML advice to generalized first price (GFP) and generalized second price (GSP) auctions.

We study the price of anarchy of the first-price auction in the autobidding world, where bidders can be either utility maximizers (i.e., traditional bidders) or value maximizers (i.e., autobidders). We show that with autobidders only, the price of anarchy of the first-price auction is $1/2$, and with both kinds of bidders, the price of anarchy degrades to about $0.457$ (the precise number is given by an optimization). These results complement the recent result by Jin and Lu [2022] showing that the price of anarchy of the first-price auction with traditional bidders only is $1 - 1/e^2$. We further investigate a setting where the seller can utilize machine-learned advice to improve the efficiency of the auctions. There, we show that as the accuracy of the advice increases, the price of anarchy improves smoothly from about $0.457$ to $1$.

Additional file 5: Table S1 PCR primers used to verify the mitochondrial genome of human flea Pulex irritans. Table S2 PCR primers used to amplify dog flea Ctenocephalides canis mitochondrial genome. Table S3 Mitochondrial genome sequences of Endopterygota insects used for phylogenetic analysis in the present study.

This paper is dedicated to developing high-efficiency face detection and tracking method for big dynamic crowds or numerous pedestrians. Three modules constitute the proposed method, i.e., face candidate generation, face candidate verification, and face target tracking. In this work, face candidates are localized using the features of the face area, edge information, and skin color. Non-face parts in the face candidates are further verified by the C-SVM learning model and then removed, by which the face targets can be generated with lower computation-complexity and satisfactory accuracy than other approaches. Finally, the face targets are tracked by an efficient and reliable searching scheme for improving the effective face detection rate. Experimental results show that the average face detection rate (FDR) of 85%, average effective FDR of 95%, a frame rate of 28–66 frames per second (fps), and about 30 faces detected per frame are obtained from various test videos with big dynamic crowds or numerous pedestrians, indicating the feasibility of the proposed method to achieve unconstrained face detection with high-efficiency and cost-effectiveness. This result makes the proposed method more attractive for the video surveillance system as compared to other approaches, especially in the high computational complexity-based methods.

Vinylethylene carbonates have been extensively used to trigger [3 + n] or [5 + n] cycloaddition via the formation of η3-allylic intermediates, while the important [4 + n] cycloaddition has not been explored yet. Here, we report a new strategy to convert vinylethylene carbonates into 4-(trimethylsilyl)but-2-en-1-ols, which can readily undergo [4 + 2] cycloaddition by in situ formation of 1,3-dienes. This novel reaction involves [PdII]-catalyzed decarboxylative silylation, [FeIII]-catalyzed vinylogous Peterson elimination, and subsequent [4 + 2] cycloaddition to afford a multisubstituted cyclohexa-1,4-diene skeleton.

The applications in high-power fields of white light-emitting diodes (WLEDs) are restricted due to their poor thermal stability. Transparent Y3Al5O12:Ce3+ phosphor-in-glass (YAG-PiG) provides an efficient way to resolve this problem. In this work, novel transparent Te/Pb-free YAG-PiGs are successfully prepared via a facile screen-printing route. It is revealed that 5 mol% Eu2O3 optimizes the concentration in substrate glass. Slight erosion of YAG particles occurs in the as-prepared samples. With increasing YAG concentration and film thickness, the intensities of photoluminescence spectra of YAG-PiGs increase. The energy transfer from Eu3+ to Ce3+ is greatly suppressed. Superior thermal stability and high quantum efficiency are obtained. The optimal optical performance values in terms of a luminous efficiency of 117.2 lm/W, a correlated color temperature of 5859 K and a color rendering index of 77.2 are achieved in YAG-PiGs. All of the results reveal that the as-prepared YAG-PiGs are promising candidates for high-power WLEDs.

We report a step-economic strategy for the direct synthesis of bridged polycyclic skeletons by merging oxidative C-H annulation and cascade cycloaddition. In the protocol, spiro[cyclopentane-1,3'-indoline]-2,4-dien-2'-ones were first synthesized by oxidative C-H annulation of ethylideneoxindoles with alkynes. Subsequent cascade [4 + 2] cycloaddition with dienophiles gave the bridged bicyclo[2.2.1]quinolin-2(1

Molecular adsorption conformations and arrangement configurations on surfaces are important structural aspects of surface stereochemistry, but their roles in steering the structures of metal-organic networks (MONs) remain vague and unexplored. In this study, we constructed MONs by the coordination self-assembly of isocyanides on Cu(111) and Ag(111) surfaces and demonstrated that the MON structures can be steered by surface stereochemistry, including the adsorption conformations of the isocyanide molecules and the arrangement configurations of the coordination nodes and subunits. The coordination self-assembly of 1,4-phenylene diisocyanobenzene afforded a honeycomb MON consisting of 3-fold (isocyano)3-Cu motifs on a Cu(111) surface. In contrast, geometrically different chevron-shaped 1,3-phenylene diisocyanobenzene (m-DICB) failed to generate a MON, which is ascribable to its standing conformation on the Cu(111) surface. However, m-DICB was adsorbed in a flat conformation on a Ag(111) surface, which has a larger lattice constant than a Cu(111) surface, and smoothly underwent coordination self-assembly to form a MON consisting of (isocyano)3-Ag motifs. Interestingly, only C3-Ag nodes with heterotactic configurations could grow into larger subunits; those subunits with heterotactic configurations further grew into Sierpinski triangle fractals (up to fourth order), while subunits with homotactic configurations afforded a triangular MON.

Ladder phenylenes (LPs) composed of alternating fused benzene and cyclobutadiene rings have been synthesized in solution with a maximum length no longer than five units. Longer polymeric LPs have not been obtained so far because of their poor stability and insolubility. Here, we report the synthesis of linear LP chains on the Au(111) surface via dehalogenative [2+2] cycloaddition, in which the steric hindrance of the methyl groups in the 1,2,4,5-tetrabromo-3,6-dimethylbenzene precursor improves the chemoselectivity as well as the orientation orderliness. By combining scanning tunneling microscopy and noncontact atomic force microscopy, we determined the atomic structure and the electronic properties of the LP chains on the metallic substrate and NaCl/Au(111). The tunneling spectroscopy measurements revealed the charged state of chains on the NaCl layer, and this finding is supported by density functional theory calculations, which predict an indirect bandgap and antiferromagnetism in the polymeric LP chains.

The complexity of enterprises’ annual reports has increased significantly under supervision. Although the interactive relations of enterprises attracted interest both among scholars and practitioners, however, the decision support information is scattered in heterogeneous and enormous data. Here introduces a new learnable deep network—which implements an inference for entity- and relation-centric representations of multilayer, dynamical but sparse system. The results show the approach supporting accurate predictions from real data extracted from financial reports. Indeed, the method shows robustness with incomplete data, thus representing a valuable tool for gaining insights on privacy-protected financial systems.

Conducting field research in Taiwan can be challenging because of the abundance of steep slopes. This study aimed to establish an automatic interpretation procedure applicable to exploring images o...

Additional file 16: Note S1. More information about inferring ancient monocot karyotypes and evolutionary trajectories to form extant chromosomes.

Additional file 4: Table S3. Meta-regression showing the possible source of heterogeneity of meta-analysis.

In classic auction theory, reserve prices are known to be effective for improving revenue for the auctioneer against quasi-linear utility maximizing bidders. The introduction of reserve prices, however, usually do not help improve total welfare of the auctioneer and the bidders. In this paper, we focus on value maximizing bidders with return on spend constraints -- a paradigm that has drawn considerable attention recently as more advertisers adopt auto-bidding algorithms in advertising platforms -- and show that the introduction of reserve prices has a novel impact on the market. Namely, by choosing reserve prices appropriately the auctioneer can improve not only the total revenue but also the total welfare. Our results also demonstrate that reserve prices are robust to bidder types, i.e., reserve prices work well for different bidder types, such as value maximizers and utility maximizers, without using bidder type information. We generalize these results for a variety of auction mechanisms such as VCG, GSP, and first-price auctions. Moreover, we show how to combine these results with additive boosts to improve the welfare of the outcomes of the auction further. Finally, we complement our theoretical observations with an empirical study confirming the effectiveness of these ideas using data from online advertising auctions.

Additional file 1: Table S1. PRISMA 2009 Checklist.

Additional file 1: Figs. S1-S20. Fig. S1. Images and genome size of coconut. Fig. S2. Heatmaps for Hi-C assembly in Cn. tall. Fig. S3. Heatmaps for Hi-C assembly in Cn. dwarf. Fig. S4. Cn. tall and Cn. dwarf Hi-C. Fig. S5. Distribution and divergence of TEs and associated PAVs. Fig. S6. Genome duplication, Ks distribution, and evolutionary dating. Fig. S7. Homologous dotplots within each Arecaceae genome. Fig. S8. Homologous gene dotploting between coconut and the other Arecaceae genomes. Fig. S9. Ks of collinear genes within each Arecaceae genome. Fig. S10. GO enrichment analysis of expansive and contracted gene families. Fig. S11. Analysis of coconut and other species gene family. Fig. S12. Homologous genes plot of coconut. Fig. S13. Homologous gene plots. Fig. S14. The inferred evolutionary trajectories to form extant Spirodela polyrhiza chromosomes. Fig. S15. The inferred evolutionary trajectories to form extant Ananas comosus chromosomes. Fig. S16. Genome variation between Cn. tall and Cn. dwarf. Fig. S17. Enrichment analysis of specific genes. Fig. S18. The expression pattern of CESA gene in different tissues of coconut. Fig. S19. Quantile-quantile plot for height phenotype. Fig. S20. Statistics on change fold of GA20ox expression on Chr. 12 with Cn.tall compare Cn.dwarf.

Additional file 5: Fig. S10. Sensitivity analyses: a) survival rate, b) pulmonary fibrosis scores.

Additional file 1: Fig. S1 Nucleotide acid and deduced amino acid sequence of DcBCH1 from ‘Kurodagosun’. Fig. S2 Nucleotide acid and deduced amino acid sequence of DcBCH1 from ‘Junchuanhong’. Fig. S3 The expression level of DcBCH1 in ‘Junchuanhong’ and ‘Kurodagosun’.

Additional file 2: Table S2. The detailed search strategy.

Additional file 2: Fig. S4 The original gel image for PCR amplification of DcBCH1 from cDNA of non-transgenic (WT) and transgenic plants (OE-3, OE-10, OE-13).

Additional file 6: Fig. S11. Funnel plots for (a) survival rate, (b) pulmonary fibrosis scores.

Additional file 24. Review history.

Additional file 3: Figure S1. Forest plot summarizing the relationship between PF models and pulmonary fibrosis scores in preclinical models of PF. Figure S2. Forest plot summarizing the relationship between MSC type and pulmonary fibrosis scores in preclinical models of PF. Figure S3. Forest plot summarizing the relationship between MSC dose and pulmonary fibrosis scores in preclinical models of PF. Figure S4. Forest plot summarizing the relationship between MSC route and pulmonary fibrosis scores in preclinical models of PF. Figure S5. Forest plot summarizing the relationship between transplant type and pulmonary fibrosis scores in preclinical models of PF. Figure S6. Forest plot summarizing the relationship between timing of MSC therapy after PF and pulmonary fibrosis scores in preclinical models of PF. Figure S7. Forest plot summarizing the relationship between geographic location and pulmonary fibrosis scores in preclinical models of PF. Figure S8. Forest plot summarizing the relationship between BMSC dose and pulmonary fibrosis scores in preclinical models of PF. Figure S9. Forest plot summarizing the relationship between ADMSC dose and pulmonary fibrosis scores in preclinical models of PF.

Drink-driving is one of the key behavioral risk factors in road traffic safety. The main purposes of this study are the identification of the influence of drivers’ subjective and objective factors on drink-driving behavior and the correlation between subjective and objective factors to design targeted measures for the prevention and control of drink-driving behavior. To analysis the influence of the subjective and objective factors on the behavior of alcohol value simultaneously. A Bayesian structural equation model is conducted with the data collected via questionnaire issued on the Internet in China. The results using the Bayesian structural equation model reveals that the subjective factors (e.g., drivers’ behavior intention and perceived behavioral control) and objective factors (e.g., age, gender, and driving years of drivers) significantly affect drink-driving behaviors. Drivers’ behavior intention is the strongest predictor, and perceived behavioral control also has a significant influence on drink-driving. Drivers who are male, older, lower driving years, driving a motorcycle or car and noncommercial vehicle have a higher probability in drink-driving. The results also suggest that there is a certain correlation between the driver's subjective and objective factors. For instance, male drivers have a more positive attitude toward drink-driving behaviors, drivers over thirty years old more cling to the region's alcohol culture and feel less guilty about drink-driving than youngsters, and truck or bus drivers perceived more disapproval of drink-driving behavior from their significant others. A more nuanced understanding of the influence of drivers to drink-driving behavior can be found in these results. These results about the influence mechanism of subjective and objective factors on drink-driving behavior of this study have implications for governments and other interested bodies for better targeting and delivery of public education campaigns and interventions.

Purpose γ-Cyclodextrin glycosyltransferase (γ-CGTase) catalyzes the biotransformation of low-cost starch into valuable γ-cyclodextrin (γ-CD), which is widely applied in biotechnology, food, and pharmaceutical industries. However, the low specificity and activity of soluble γ-CGTase increase the production cost of γ-CD, thereby limiting its applications. Therefore, the present study aimed at optimizing an economical medium for high production of γ-CGTase by the recombinant Escherichia coli (E. coli) BL21 (DE3) and evaluating its enzymatic properties and product specificity. Methods The γ-CGTase production was optimized using the combination of Plackett-Burman experimental design (PBD) and Box-Behnken design-response surface methodology (BBD-RSM). The hydrolysis and cyclization properties of γ-CGTase were detected under the standard assay conditions with buffers of various pHs and different reaction temperatures. The product specificity of γ-CGTase was investigated by high-performance liquid chromatography (HPLC) analysis of three CDs (α-, β-, γ-CD) in the biotransformation product of cassava starch. Results The γ-CGTase activity achieved 53992.10 U mL−1 under the optimum conditions with the significant factors (yeast extract 38.51 g L−1, MgSO4 4.19 mmol L−1, NiSO4 0.90 mmol L−1) optimized by the combination of PBD and BBD-RSM. The recombinant γ-CGTase exhibited favorable stability in a wide pH and temperature range and maintained both the hydrolysis and cyclization activity under the pH 9.0 and 50 °C. Further analysis of the products from cassava starch catalyzed by the γ-CGTase reported that the majority (90.44%) of product CDs was the γ form, which was nearly 11% higher than the wild enzyme. Cyclododecanone added to the transformation system could enhance the γ-CD purity to 98.72%, which is the highest purity value during the transformation process reported so far. Conclusion The yield of γ-CGTase activity obtained from the optimized medium was 2.83-fold greater than the unoptimized medium, and the recombinant γ-CGTase exhibited a favorable thermal and pH stability, and higher γ-cyclization specificity. These results will provide a fundamental basis for the high productivity and purity of γ-CD in the industrial scale.

Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity1-4. Sparse taxon sampling has previously been proposed to confound phylogenetic inference5, and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363genomes from 92.4% of bird families-including 267newly sequenced genomes produced for phaseII of the Bird 10,000Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species.

A transition-metal-free double addition/double rearrangement domino reaction affording CF3-substituted pyrimidines was developed, which enables the one-pot construction of five new bonds, namely three C-C bonds and two C-N bonds. The keys to achieve this highly efficient reaction include the delicate design of the bis-nucleophiles in situ generated from the dimerization of alkyl nitriles and the use of trifluoroacetimidoyl nitriles containing C[double bond, length as m-dash]N, C[triple bond, length as m-dash]N, and CF3 groups as the reactant. The mechanistic studies by the experiments and DFT calculations reveal that the transformation involves two addition and two unprecedented rearrangement processes.

In the motor-driven high-voltage circuit breaker, as the power executive part of the operating mechanism, the performance of motor plays a decisive role in the opening and closing speed of the high-voltage circuit breaker. Therefore, the design of a high-power permanent magnet synchronous motor (PMSM) with high torque density and low torque ripple is the basis for the stable operation of high-voltage circuit breakers. According to the current use of PMSM, it is found that the cogging torque caused by the interaction between the permanent magnet field and the cogging of stator, it will cause oscillation at the end position of circuit breaker. According to the practical problems, the method of rotor slanting pole and opening hole is adopted. Through electromagnetic simulation calculation and actual product test, finally, we can get the optimal solution of the cogging design of PMSM for high-voltage circuit breaker.