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Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

The application of thermosensitive fluorescent supramolecular polymers in advanced optical materials, chemical sensors, artificial optical devices, and external stimulus responses remains underdeveloped. In this study, we introduced a novel method for constructing a mechanically interlocked fluorescent supramolecular polymer utilizing host–guest interactions, including C–H···π interactions and π–π stacking. This polymer exhibits outstanding temperature-sensitive fluorescence properties and is environmentally friendly due to its recyclability. Leveraging the polymer’s fluorescence response at critical temperature ranges, we developed a high-temperature warning device. This device utilizes the temperature-sensitive fluorescence characteristic of the polymer to indicate dangerous temperature levels, thereby demonstrating its potential in practical safety applications.

The Global Justice Index is a multiyear research project based at Fudan Institute for Advanced Study in Social Sciences that assesses the contributions made by each country to achieving greater global justice. We have published results for yeas from 2010 to 2020 in Global Justice Index Reportfrom 2019 to 2022, and are now presenting our fifth year of results, covering data from 2021 in Global Justice Index Report 2023, which is an updated version of previous years’ reports. But, we have been improving our index year by year to with changes that have taken place globally. We have also refined our imputation methodology to better address the challenge of missing data. The report consists of four sections: introduction, findings, main results, and conclusion. In the introduction, we discuss the development of the conceptual framework and evaluative principles to justify our selection of the dimensions and indicators for measurement. Next, in the findings section, we report the data, indicators, and our results for each country for each of the 10 issues we identify, and provide regional comparisons for Asia, Europe, North America, Latin America, Africa, and Oceania. In the following section, we present the main results for the global justice indices, and report the ranking of each country’s contribution to achieving greater global justice. In the final section, we discuss the applications and limitations of the index and potential further research trajectories.

As one of the main components of a high-precision time measurement system, the time-to-digital converter (TDC) is widely used in many scientific research fields. A two-stage high-precision and wide-range TDC application-specified integrated circuit (ASIC) based on a differential delay line using delay-locked loop (DLL) technology is presented. The TDC ASIC consists of a coarse measurement stage for expanding the measurement range and a fine measurement stage for high-precision measurement. The coarse stage is achieved by two binary counters with dual edges sampling to avoid the metastable state. The fine stage is achieved by a voltage-controlled delay line (VCDL). The VCDL utilizes differential delay cells to mitigate the susceptibility to the power supply noise and the substrate noise. A DLL is adopted to compensate for variations in process, voltage, and temperature (PVT). The TDC AISC has been fabricated in a 180-nm CMOS technology and tested. A dynamic measurement range of $6.55~\mu $ s and a time resolution of 200 ps are achieved with a reference clock of 312.5 MHz. Test results show that the precision is 65.6-ps root-mean-square (rms), and the differential nonlinearity is within -0.34–0.40 LSB.

Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.

Factor analysis is widely utilized to identify latent factors underlying the observed variables. This paper presents a comprehensive comparative study of two widely used methods for determining the optimal number of factors in factor analysis, the K1 rule, and parallel analysis, along with a more recently developed method, the bass-ackward method. We provide an in-depth exploration of these techniques, discussing their historical development, advantages, and limitations. Using a series of Monte Carlo simulations, we assess the efficacy of these methods in accurately determining the appropriate number of factors. Specifically, we examine two cessation criteria within the bass-ackward framework: BA-maxLoading and BA-cutoff. Our findings offer nuanced insights into the performance of these methods under various conditions, illuminating their respective advantages and potential pitfalls. To enhance accessibility, we create an online visualization tool tailored to the factor structures generated by the bass-ackward method. This research enriches the understanding of factor analysis methodology, assists researchers in method selection, and facilitates comprehensive interpretation of latent factor structures.

Heterogeneity is a major obstacle to the success of CAR-T therapy in treating solid tumors. The complex tumor microenvironment and varying phenotypes of tumor cells might result in antigen escape, drug resistance, and tumor recurrence. To address this issue, we proposed to use lipid-modified fluorescein isothiocyanate (Lip-FITC) as an artificial ligand to normalize the phenotypes of solid tumor cells. In murine cutaneous melanoma and colon adenocarcinoma that prefer to utilize exogenous long-chain fatty acids, we observed much more uptake of Lip-FITC and significantly increased FITC fluorescence on tumor cell membranes than normal cells. This specific exogenous labeling with FITC enhanced the recognition and selectivity of CART cells in solid tumors, bypassing the limitations derived from antigen expression differences in adoptive cell therapies. Lipid metabolism analysis and in vitroexperiments demonstrated the sufficient uptake of long-chain fatty acid (LCFAs)-modified Lip-FITC by solid tumor cells, as well as satisfactory ligand assembly on cell membranes. In solid tumor model, the treatment induced the recognition and initiation of CART cells and successfully suppressed tumor progression through T-cell immunity.

Photocatalytic [3 + 2] cycloadditions and control of stereochemistry have remained a substantial challenge, particularly in the context of heterocycle synthesis; sporadic successful examples have involved enantioselective [3 + 2] photocycloaddition between redox-active direct group-containing cyclopropanes and alkenes for creation of cyclopentanes. Herein, we report a cooperative catalytic system comprising a chiral nickel Lewis acid catalyst and an organic photocatalyst fueled by visible-light irradiation that allows for the hitherto elusive asymmetric [3 + 2] photocycloaddition of β-keto esters with vinyl azides under redox-neutral conditions. This protocol enables highly enantioselective construction of polycyclic densely substituted 3,4-dihydro-2H-pyrrole heterocycles featuring two contiguous tetrasubstituted carbon stereocenters, including a useful chiral N,O-ketal motif that is not easily accessible with other catalytic methods. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of dual roles of nickel catalysts by the catalytic formation of the substrate/Ni complex, assisting both photoredox event and enantioselective radical addition.

The Global Justice Index is a multiyear research project based at Fudan Institute for Advanced Study in Social Sciences that assesses the contributions made by each country to achieving greater global justice. We have published results from 2010 to 2019 in Global Justice Index Report, Global Justice Index Report 2020, Global Justice Index Report 2021, and we are now presenting our fourth-year results for 2020 in Global Justice Index Report 2022, which is an updated version of previous years’ reports. This year, we take into account changes to global justice influenced by the COVID-19 pandemic. The report consists of four sections: introduction, findings, main results, and conclusion. In the introduction, we discuss the development of the conceptual framework and evaluative principles to justify our selection of the dimensions and indicators for measurement. Next, in the findings section, we report the data, indicators, and our results for each country for each of the 10 issues we identify, and provide regional comparisons for Asia, Europe, North America, Latin America, Africa, and Oceania. In the following section, we present the main results for the global justice indices, and report the ranking of each country’s contribution to achieving greater global justice. In the final section, we discuss the applications and limitations of the index and potential further research trajectories.

Oligo[n]rotaxanes are one of the most extensively studied categories of mechanically bonded macromolecules. In this study, a supramolecular oligo[2]rotaxane is successfully constructed driven by platinum(II) metallacycle and pillar[5]arene-based host–guest interactions in an orthogonal way. The supramolecular oligo[2]rotaxane is further applied in fabricating a light harvesting system.

Dosage forms with multiple APIs pose greater analytical difficulties than single-API dosage forms. This study evaluates near-infrared analysis of tablets nominally containing 4 mg of chlorpheniramine maleate and 10 mg [...]

Research on information technology (IT) outsourcing adoption has been confined to a single-country perspective. The understanding of how country-specific variables influence the adoption of IT outsourcing is limited. This study uses new institutional economics to build a framework that links country-level-factors to the adoption of IT domestic outsourcing. The authors suggest that country-level factors, such as the maturity of the IT-related legal system, social trust, uncertainty avoidance, Internet penetration, and the maturity of the IT outsourcing market, affect the opportunism costs and coordination costs involved in domestic IT outsourcing and influence its adoption among firms. The results show that the maturity of the IT-related legal system, social trust, and the maturity of the IT outsourcing market are positively associated with IT outsourcing adoption. The authors conclude the paper with a discussion of the study's implications for practice and future research. Keywords: Coordination Costs, Country Environments, IT Adoption, IT Outsourcing, Opportunism Costs, INTRODUCTION Since the landmark decision by Eastman Kodak to hand over IT functions to IBM, Businessland, and DEC, the practice of outsourcing a firm's IT facilities and services to outside [...]

Near-infrared (NIR) assay and content uniformity of tablets provide fast, accurate means of monitoring tablet production that are in step with FDA's process analytical technology initiative. The authors discuss the [...]

Enzyme-responsive nanomaterials are emerging as important candidates for bioanalytical and biomedical applications due to their good biocompatibilities and sensitivities. However, the lack of promising operation platforms compatible with enzyme responsiveness greatly limits the scope and functionality of smart materials. Herein, we report the design and synthesis of a naphthalene-functionalized organoplatinum(II) metallacycle 1by means of coordination-driven self-assembly, which is subsequently exploited as the organometallic platform to enable enzyme-responsive supramolecular materials. Specifically, a [2 + 2] self-assembled metallacycle 1first self-assembles into nanosheets in aqueous solution, which can further transform into vesicles with the introduction of β-cyclodextrin (β-CD) because of the formation of a bola-type supramolecular amphiphile β-CD-1. Interestingly, these vesicles show rare α-amylase responsiveness, as demonstrated by structurally transforming back into nanosheets after the addition of α-amylase to their solutions due to the enzyme-induced degradation of cyclodextrins. We also demonstrate the potential application of the self-assembled vesicles in amylase-responsive controlled release.

The characteristics of the solid phase, namely the volume fraction, particle size, and morphology, are dominant variables that can determine the viscosity of the semi-solid slurry. However, particle size and morphology were always being ignored and the solid fraction was simply determined using the temperature in the conventional power-law viscosity, resulting in a disagreement in the viscosity values in different researches. To make the power-law viscosity model more accurate for predicting the filling process of semi-solid die casting, it is essential to modify this viscosity model based on particle characteristics. Therefore, there is a fundamental demand to prepare semi-solid slurries with different α-Al phase features at first. This is achieved in this study by two kinds of heat history controlling methods: remelting and solidification, which can get slurries with spherical structure and dendric structure, respectively. The semi-solid 357.0 slurries with 0.11-0.43 solid fraction, 137-182μm particle size, and 0.81-0.90 shape factor were prepared in the remelting process, while dendritic structures (shape factor<0.5) with 0.1 and 0.3 solid fractions were obtained by solidification controlling from the full liquid state. Besides, the effect of parameters on the evolution of the α-Al phase has been discussed. These slurries with different solid features will be further used to quantify the influence of primary phase characteristics on rheological behavior and make the power-law viscosity model more accurate for simulation.

Following the rapid growth of the automotive and communication industries, components with high quality and low cost are eagerly desired in China. Various technologies have been developed in China to meet the demand, while semi-solid processing (SSP) of alloys and composites is one of the most successfully developed and practically applied technologies. The major SSP applied in China is the rheocasting in terms of the Swirled Enthalpy Equilibration Device (SEED) process. In this review, we start with a brief reviewing some common slurry preparation methods and recent innovations of the SEED process. Subsequently, we describe the general situation and some recent examples of successful development and applications of SSP in China. Lastly, the future directions in SSP of alloys and composites are highlighted in this frontier research field at the end of this review.

The flow behavior of semi-solid slurry determines the quality of the castings produced by the semi-solid forming process. Many studies have done to investigate the flow behavior of slurry under different conditions, and results show that the rheological behavior of slurry with dendritic structure is inappropriate for semi-solid forming. In this study, slurries with varying morphologies of grain for the same alloy with the same fraction solid have tested using a partial filling method. The SEED process was employed, and the pouring temperature adjusted to prepare semi-solid slurries with different grain morphologies. The flow pattern, entrapped air during the filling process, and also microstructure of the samples were examined to characterize the macro and micro flow behavior. The results show that a turbulent macro-flow, leading to entrapped air, and severe segregation appeared in the sample using slurry of Tpour ≥ 660 °C . For the slurry of Tpour < 660 °C, none of the three phenomena found in the sample. This investigation further showed that the detriment of dendrite on the semi-solid forming process, and implied that large size dendrite in semi-solid slurry must avoided.

Spherical morphology is the typical characteristic of the microstructure in semi-solid slurries, while the formation mechanism of these spherical grains is still unclear, especially the migration of the solid-liquid interface under different process conditions. This study will focus on the effect of pouring temperature and swirling on the morphology of grains. A phase field-lattice-Boltzmann method using parallel computing and adaptive mesh refinement (Para-AMR) was employed to study the FCC α-Al phase evolution in binary Al-Si aluminum alloy. Study results represent that the pouring temperature has a significant influence on the morphology of the α-Al grains. Low pouring temperature is a benefit for the formation of spherical microstructures. And the swirling can refine the microstructure under high pouring temperature.

Owing to its low cost, short process and low energy consumption, semi-solid processing (SSP) of aluminum (Al) and magnesium (Mg) alloys has been considered as a competitive approach to fabricate complicated components with excellent performance. Over the past decade, significant progress has been achieved in deeply understanding the SSP process, the microstructure and performance of the fabricated components in China. This paper starts with a retrospective overview of some common slurry preparation methods, followed by presenting the performance and the underlying mechanisms of SSP fabricated alloys. Then, the mainstream opinions on the microstructure evolution and rheological flow behavior of semi-solid slurry are discussed. Subsequently, the general situation and some recent examples of industrial applications of SSP are presented. Finally, special attention is paid to the unresolved issues and the future directions in SSP of Al and Mg alloys in China.

Background: Cuscutae Semen (CS) is reported to show a hepatoprotective effect. Chlorogenic acid, hyperoside and astragalin are three major biologically active components from CS. Objective: A sensitive method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated to quantify the three components in rat plasma and was successfully used to study pharmacokineticsin liver injury rats. Methods: Plasma samples were prepared with protein precipitation by acetonitrile. Chromatographic separation was achieved on ACQUITY-XBridge BEH C18 column with gradient elution using the mobile phase containing 0.05% formic acid in water (A) and acetonitrile (B). The three components were quantified using Electrospray Ionization (ESI) source in the negative multiple Reaction Monitoring (MRM) mode. Results: Calibration curves of each analyte showed good linearity with correlation coefficients over 0.99. Accuracies (RE%) and precisions (RSD%) were within 15%. The method was stable. Recovery of the target compounds in plasma samples ranged from 87.00% to 102.29%. No matrix effect was found to influence the quantitative method. Conclusion: The UPLC-MS/MS method met the acceptance criteria and was successfully applied to the simultaneous determination of chlorogenic acid, hyperoside and astragalin in rat plasma for the first time. It is suitable for pharmacokinetic application in liver injury rats. It provides the foundation for further development and utilization of the hepatoprotective effect of cuscutae semen.

The phase compositions of surface and interior in Ti-32Nb-4Sn metastable b alloy were investigated. It was found that this alloy exhibits surface effect significantly different from the effects reported in Ti-10V-2Fe-3Al, Ti-22Nb-9Zr and the other titanium alloys. The surface of Ti-32Nb-4Sn specimen quenched from single b phase region was characterized by dominant b phase and a few of α″ and ω phase. While in the interior of the alloy, a large amount of α² martensite phase was observed in addition to b phase The orientation relationship between the α″ martensite and β phase is (110)β∥(002)α″, (020)β∥(022)α″ and [001]β∥[100]α″.

Supplemental Digital Content is available in the text.Identifying outcome predictors for ischemic stroke is beneficial for choosing correct intervention protocols. Thus, it is necessary to systemically evaluate histological outcome-associated changes such as hemodynamics, behavior, and body weight during the early phase of ischemia. Here, 50 mice were subjected to 45-min middle cerebral artery occlusion (MCAO) using Longa’s method. Hemodynamic changes were monitored by Doppler laser probe, and behaviors were evaluated by scales while the tissues were visualized by staining. The results by correlation analysis demonstrated that with a probe located near the posterior boundary zone of MCA territory, the latency of anoxic depolarization, as well as the cerebral blood flow reduction during MCAO were confirmed to be predictors for the infarct volume on day 3 post-ischemia; histology showed that the risk of a space-occupying secondary hemorrhage was significantly correlated with the increase of infarct volume versus the traditional Bederson’s neurological deficit scale, a renewed combined behavioral scoring method performed nicely to reflect the severity of tissue lesions. Weight loss was a valuable metric for the enlargement of both infarct volume and secondary hemorrhage. Monitoring changes during early-phase ischemia may benefit the optimization of ischemia models and the discovery of potential intervention targets.See Video Abstract, http:/links.lww.com/WNR/A601).

A new method was developed to optimize the microwave heating thickness of the spent automobile catalyst in order to improve the uniform distribution of the temperature field. The average penetration depth and the microwave heating thickness of the spent automobile catalyst were calculated by Gauss model and numerical calculation based on dielectric loss tangent and reflection loss. The results showed that the spent automobile catalyst was a medium loss material. The average penetration depth was 1.11 m from room temperature to 800 °C. The optimum microwave heating thickness of the spent automobile catalyst was about 0.83 m or 0.75 times of the average penetration depth. Industrial application analysis indicated that the optimization of heating thickness could improve the uniform distribution of the temperature field and reduce energy consumption.

The SEED (Swirled Enthalpy Equilibrium Device) process was used to produce semi-solid slurries. One of the factors that controls whether or not a slug can be used to produce high quality castings is the solid fraction distribution within the slug, and the solid fraction distribution is strongly dependent upon the temperature distribution. In this study, a model has been developed using ProCAST to investigate the relationship between process parameters and the temperature distribution within slugs. The parameters examined included the heat transfer coefficient between the crucible and slug, the heat transfer coefficient between the crucible and air, the slug diameter, and the initial melt temperature (pouring temperature). It was found that the most important parameters controlling the temperature distribution within slugs were the crucible size and the heat transfer coefficient between crucible and air. Adjustment of other parameters had little influence on the temperature distribution. Processing parameters will be discussed in order to allow the SEED process to be used for the production of large diameter slugs (>100 mm), and for narrow freezing range (0.3<fs<0.5, fs is fraction solid) alloys such as 6063.

Macrocyclic arenes have emerged as pivotal scaffolds in supramolecular chemistry. Despite their significant contributions to molecular recognition and diverse applications, challenges persist in the development of macrocyclic arene-based crystalline materials, particularly in achieving porosity and addressing limitations in adsorption efficiency resulting from the small cavity sizes of existing macrocyclic arenes. In this study, we present the design and synthesis of a novel macrocyclic arene, clamparene (CLP), featuring a rigid backbone, easy synthesis, and a sizable cavity. CLPself-assembles into one-dimensional sub-nanotubes that further organize into a three-dimensional porous framework in the solid state. The crystalline solid of CLPexhibits potential as a porous crystalline adsorbent for various benzene-based contaminants with rapid adsorption kinetics, large uptake amounts, and good recyclability.

In the field of material production and application, strength and hardness are the two most common properties of metallic materials. It’s one familiar phenomenon that the hardness of one certain alloy has positive relationship with its strength in conventional dendritic alloys. When it comes to non-dendritic semi-solid alloys, it’s unclear that the relationship is still right or not. In this paper, the molecular mechanics, as well as finite element simulation and experimental verification were combined to study the internal deformation regularity of metallic material and the correlation between the two parameters was illustrated. Firstly, the displacement of solid atom in metallic crystal cell was well described in the view of energy cost. Secondly, the total strain amount under local indenting deformation (resistant boundary) and overall impressing deformation (free boundary) were compared to study the correlation between hardness and compression strength in semi-solid globule grain alloy. Finally, the data collected in semi-solid processed products was applied to be compared against traditional casting and wrought aluminum alloys.

Semi-solid aluminum slurries have globular grains, different from traditional dendritic solidification microstructures. The mechanism responsible for the formation of these globular grains is still in dispute. Some researchers suggest that the globular grains are formed by fractured dendrites, while others report it is due to copious nucleation. This study will model the growth of the α-Al phase during the production of semi-solid slurries using the swirled equilibrium enthalpy device (SEED) process, where liquid alloy with a low superheat is poured into a steel crucible and swirled within the semi-solid region. Experimental observations have shown that the final microstructure of the slurry produced by the SEED process is relatively non-uniform, with large dendrites at surface and fine spherical particles at the center. Open source code for the phase field method has been adopted to simulate the different microstructural evolution for semi-solid alloy 357.0. The effect of localized temperatures under isothermal condition on the morphology of the α-Al particles has been investigated according to the special conditions of the SEED process. In addition, suggestions for modifying the slurry production to achieve more uniform microstructure are discussed.

Controlling the morphology of the microstructure of the slurry is important during semi-solid die casting. For this project, semi-solid slugs were produced using the SEED (Swirled Enthalpy Equilibrium Device) process, where a fully liquid metal is poured into a steel crucible and cooled into the semi-solid temperature range, and the crucible and slurry are then swirled and cooled to the appropriate temperature (and solid fraction) for semi-solid casting. The pouring temperature of the melt into the crucible during SEED processing has been shown to influence the morphology and size of the aluminum solid particles within the slurry, which can influence the distribution and segregation of the solid particles during die casting. In this study, a specially-designed die with a serpentine-shaped flow channel has been used to study the distribution of the solid particles during semi-solid die casting. The experimental results show that a dendritic structure is formed when the liquid is poured from a high temperature, while a globular semi-solid morphology is more easily formed when poured from a low superheat. The current results also show that a dendritic structure leads to severe segregation during die casting.

BackgroundEmerging evidence suggests that DNA methylation in maternal blood is a promising target for intrauterine growth retardation (IUGR) screening, a common developmental toxicity. Here, we aimed to screen out IUGR-related DNA methylation status in maternal blood via high-throughput profiling.MethodsPregnant Wistar rats were subcutaneously administered nicotine (1 mg/kg) twice per day from gestational day (GD) 11 to GD20 to establish the IUGR model. MeDIP array assays and the following GO analysis were used to evaluate DNA methylation status in maternal blood. One placental development-associated gene was selected for further confirmation.ResultsGenes regulating the development of multiple organs and major body systems had changed DNA methylation frequencies in the maternal blood of IUGR rats. Placental development, which can affect the development of multiple fetal organs and induce IUGR, is a hypermethylated cluster consisting of four significantly changed genes, including syncytin b (Synb), Lrrc15, Met, and Tex19.1. With the most significant change, Synb hypermethylation in maternal blood was confirmed by bisulfite-sequencing PCR (BSP). Moreover, decreased Synb expression and histological changes were observed in IUGR placentae.ConclusionThe IUGR-associated DNA methylation profile in maternal blood, such as placenta-related Synb hypermethylation, provides evidence for further studies on possible IUGR biomarkers.

With the growing popularity of multimodal data on the Web, cross-modal retrieval on large-scale multimedia databases has become an important research topic. Cross-modal retrieval methods based on hashing assume that there is a latent space shared by multimodal features. To model the relationship among heterogeneous data, most existing methods embed the data into a joint abstraction space by linear projections. However, these approaches are sensitive to noise in the data and are unable to make use of unlabeled data and multi-modal data with missing values in real-world applications. To address these challenges, we proposed a novel multimodal deep-learning-based hash (MDLH) algorithm. In particular, MDLH uses a deep neural network to encode heterogeneous features into a compact common representation and learns the hash functions based on the common representation. The parameters of the whole model are fine-tuned in a supervised training stage. Experiments on two standard datasets show that the method achieves more effective results than other methods in cross-modal retrieval. 随着网络上多模态数据的普及, 海量多媒体数据库上的跨模态检索成为研究的热点。跨模态检索方法假设多个模态的数据特征之间存在一个共享的潜在特征空间。因此, 为了建立多模态数据之间的关联, 大部分已有方法通过线性映射将多模态数据分别映射到同一个共享特征空间。但是, 该类方法对于数据中的噪声比较敏感, 并且也无法使用现实场景中的无标记的数据或缺失模态的数据。针对该问题本文提出了一种新的基于多模态深度学习的哈希算法。该方法使用深度神经网络结构将异构特征映射为一个共同的压缩表示, 并在此表示的基础上学习哈希函数。整个模型的参数通过有监督的方式进行训练。在两个标准数据集上的实验结果显示本文的方法能够有效的完成跨模态检索的任务。

Immunity is a balanced status with adequate biological defenses to recognize and fight “non-self”, as well as adequate tolerance to recognize “self”. To maintain this immune homeostasis, a well-organized T cell immune network is required, which in part depends on the well-controlled development of alternative effector T cells, with different cytokine repertoires. Recent researches have pointed that developing fetal T cells network is a remarkably sensitive toxicological target for adverse factors in early life. Epidemiological and experimental studies showed an inseparable relationship between T cell developmental toxicity and immune diseases in adults. Considering that the inflammatory and immune disorders have become a growing health problem worldwide, increasing attention is now being paid to the T cell developmental toxicity. We propose that adverse factors may have programming effects on the crucial functions of immune system during early life which is critical for fetal T cell development and the establishment of the distinct T cell repertoires balance. The permanently disturbed intrathymic or peripheral T cell development may in turn lead to the immune disorders in later life. In this manuscript, we reviewed how adverse factors affected T cell development in early-life with the consequence of the immune dysfunction and immune diseases, and further elucidate the mechanisms. These mechanisms will be helpful in prevention and treatment of the increased prevalence of immune diseases by interfering those pathways.

The development of sensors for selective detection of cyanide ion (CN−) is an important mission to accomplish because of the versatility and toxicity of CN−. In the present work, an “ensemble”-based colorimetric and fluorescent sensor (L2-Zn2+) for CN−ion has been developed. The addition of cyanide ions removed Zn2+from the ensemble (L2-Zn2+) in aqueous medium, resulting in a color change of the solution from red to buff and a “turn-on” fluorescent response. Also, the sensitivity of both the fluorescence- and colorimetric-based assay is below the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. In addition, test strips, which served as convenient and efficient CN−test kits, were fabricated based on the sensor. Notably, the selective detection of cyanide with L2-Zn2+for practical application was also performed in sprouting potatoes.

To understand biosafety’s current situation in laboratory animal research and risk factors affecting occupational health. Compliance surveys were conducted by questionnaire via Questionnaire Star (an application app on the Internet) in Chinese. Thirty-nine anonymous questionnaires were collected. The surveyed institution has established 24 types of ABSL(Animal Biosafety Laboratory) and biosafety management organizations and systems equipped with safety equipment. Our study also suggests that the principal of the laboratory establishment fails to perform supervision and inspection responsibilities, the inappropriate design of the animal biosafety laboratory, non-standardized personnel training and health management, non-strict waste management, and insufficient emergency management. The administrative department and work units should address certain safety and occupational health risks in laboratory animal research. The author proposes control strategies based on organizational guarantee, personnel management, emergency management, etc., to help prevent risks and ensure occupational health. Due to regional limitations and small sample size, the results may not be generalisable to all parts of the world. However, some of the key common issues may also be present in other regions, so we believe that this research still has some relevance.

Considerable progress in the construction of efficient fluorescence-resonance energy transfer (FRET) systems has promoted the development of artificial energy transfer materials. However, despite recent advances, the exploration of efficient and easy strategies to fabricate novel supramolecular systems with FRET activities is still a challenge. Here, we report that a two-step FRET system was successfully achieved, driven by platinum metallacycle based host–guest interactions. The two-step FRET system is used for the preparation of a white-light-emitting diode and serves as a nanoreactor for the photosynthetic process. This work offers a strategy for the fabrication of FRET systems and opens opportunities for functional materials constructed by platinum(II) metallacycle based host–guest interactions.

Supramolecular chemistry has received considerable attention in host-guest recognition. The structure-response relationship of host-guest recognition system is a meaningful issue. Herein, a series of tripodal nitrogen mustard derivatives (TMs) have been developed in this paper. By rationally design the intramolecular alkyl chain lengths of host, the host-guest binding model have been successfully tuned, which underwent a transformation from π-πto multiple hydrogen bonds. This process enhances the host-guest binding force and recognition efficiency.

Semi-solid alloy slurries with different temperature distributions have diverse flow patterns of the slurries during die casting filling process. This different flow patterns can lead to various degrees of front separation of the slurry metal from the die cavity during die filling process. This separation can result in air entrapment, which is one of the origins for gas porosities and blisters occurred during followed heat treatment. Therefore, in this paper, the effects of slurry temperature distribution on filling patterns during die casting process were investigated. Based on partial filling experiments, positive and negative gradient temperature distribution, together with two homogeneous conditions 575°C, 579°C were compared by computer simulation. The results indicate that the positive gradient temperature condition of 357.0 slurry is more suitable for the semi-solid die casting of the connector, and 7 °C temperature gradient in slurry is appropriate for good filling.

One-phase modelling is widely used as an optimization and design tool for semi-solid casting process. By this approach, semi-solid alloy is taken as a homogeneous fluid and flow behaviours are represented by using the rheological properties of the mixture. A single set of conservation equations is solved to simulate the mould filling, without considering the different motilities between the liquid and the solid phase. Therefore, defects due to phase segregation cannot be predicted and particle tracking cannot be carried out. This study is focused on multiphase (i.e. a liquid-particle-air system) modelling during the semi-solid filling process of a thin-walled component. By using this approach, the solid phase is treated as a power law fluid and the phase interactions among the phases are introduced for the semi-solid alloy system. Practical semi-solid die casting is carried out for verification of phase segregation. The final distribution of air is calculated and proved by practical blistering examination. The simulation results are verified to be accurate in a reasonable range, indicating an approach for modelling semi-solid filling including the formation (and avoidance) of blisters.

Asphaltene supermolecules extracted from coal consist of highly condensed polyaromatic units and peripheral aliphatic chains, which is a natural source with high carbon content. In this study, we demonstrate that the asphaltene can be used as an ideal supermolecular carbon precursor for the fabrication of carbon nanosheets by self-assembly via π–π and hydrogen bonding interactions with a sheet-structure-directing agent of graphene oxide. The overall thickness of the obtained asphaltene based carbon nanosheets can be tuned from 13 ± 3 to 41 ± 5 nm. These carbon nanosheets show an electrical conductivity of ca. 450 S m–1. When they are used as electrode materials for supercapacitors, the carbon nanosheets demonstrate a specific capacitance of 163 F g–1even at a current density of 30 A g–1tested in a three-electrode system, due to high electrically conductive networks and short diffusive paths. The maximum specific gravimetric capacitance and surface area-normalized capacitance in two-electrode system are 191 F g–1and 43 μF cm–2, respectively, indicating very high utilization of the available surface area. These results prove that asphaltene is a promising molecular precursor for the preparation of energy materials, further displaying an efficient route for staged conversion of coal that is abundant in nature.

One pumping unit corresponding to one well is the principal oil production pattern for cluster well at the present time. When oil exploitation comes into mid-later period, reducing of permeability will result in falling of oil output and production efficiency as well as increasing of energy cost. Therefore, the production pattern of one well-one pumping unit has been unsuitable to satisfy the demand of cluster well production technology. This paper presents a novel cluster well pumping unit based on slider-crank mechanism. Well load pairing balance way was adopted in our design, and therefore the weight of pumping unit drops greatly. A dynamics model of the unit was established, and contrastive analysis with the beam pumping unit was performed. At the present time, the practical prototype has been used in Chinese oil field and it runs efficiently.

Aimed at the serious problem of N80 tubing failure in the drainage of CBM (Coal bed methane) well, it can define the failure into two types: eccentric failure wear and the corrosion failure, through analyzing the well space structure, the stress and the chemical reaction on the tube in the coal bed water. The main reason is well deviation, instability of rod string and rod vibration. It makes sucker rod contacts with the N80 tube, when the sucker rod is up and down, the friction exists between the sucker rod and the tube, which leads to the tube wear out. Corrosion failure may happened in the condition that there are some acid anions in the coal seam water, such as HS-, S2-, Cl-, HCO3-, SO42-, CO32-, etc. These ions react with N80 tubing that corrodes and destroys the N80 tube. In this paper, we suggest to replace the N80 tube with the UHMWPE (ultra-high molecular weight polyethylene) liner tube. This is capable to reduce the wear and corrosion rate effectively. The field tests show that it is still useful over 600 days, which means that the serving life of UHMWPE liner tube can be increased over 50 percent than others. Therefore, it has a significant meaning to popularize UHMWPE liner tube in the CBM well.

Two clearly Tgbeing observed in DSC thermogram indicated a micro-phase separation in PU-I. The corresponding PU films showed excellent mechanical properties with a tensile strength of 27.5MPa and an elongation at break of 996%.

Existing non-destructive test methods are usually ineffective in detection of surface breaking cracks with large depths in concrete structure. This paper introduces a method suitable for detection of deep cracks based on surface wave time reversal theory. A numerical simulation based on the finite element model is performed to investigate surface cracks detection. A damage index was defined based on the correlation coefficient between the actuated and the reconstructed wave signals. The results demonstrated that the presence of crack had a significant influence on the propagation characteristics of surface waves along concrete. Cracks in different sizes were introduced and correlated with the damage index. Enlarging the crack depth resulted in an increase in the distortion of reconstructed signals, and a higher damage index was obtained. The results illustrated the effectiveness of the surface wave time-reversal process in identifying cracks in concrete structures.

Chilling is a cost-effective and safe method of immobilising flies in Drosophilaexperiments. However, should condensation form on the plate, it would be fatal to the flies. Here we describe a modified cooling method using reusable commercial ice pack(s) (ca. 400 ml, 2–3 cm tall) rather than crushed ice. The ice pack is covered with a piece of filter paper which absorbs the condensed water formed on the cold surface, and the moistened filter paper does not wet the wings of flies inverted onto it. An ice pack (ca. 400 ml) takes effect in at least 1 h, and its height is shorter than the maximum specimen height of a dissecting microscope, so that flies can be checked while they remain on the cold surface. This method overcomes the disadvantages of the indigenous cooling anaesthetising approach and makes it practically feasible. We also describe an easy-to-make fly-transferring toolkit which will greatly facilitate fly transferral when it is combined with our chilling method. In our design, the flies were directed out of a vial by a blue pipette tip, which is inserted in a foam stopper and channelled down into another vial by a glass funnel inserted in another foam stopper which is escape-proof.

Roles, their emotion, and interactions between them are three key elements for semantic content understanding of movies. In this paper, we proposed a novel movie summarization method to capture the semantic content in movies based on a string of IE-RoleNets. An IE-RoleNet (interaction and emotion rolenet) models the emotion and interactions of roles in a shot of the movie. The whole movie is represented as a string of IE-RoleNets. Summarization of a movie is transformed into finding an optimal substring with user-specified summarization ratio. Hierarchical substring mining is conducted to find an optimal substring of the whole movie. We have conducted objective and subjective experiments on our method. Experimental results show the ability of our method to capture the semantic content of movies.