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Circulating exosomes delivering microRNAs are involved in the occurrence and development of cardiovascular diseases. How are the circulating exosomes involved in the repair of endothelial injury in acute myocardial infarction (AMI) convalescence (3‐7 days) was still not clear. In this study, circulating exosomes from AMI patients (AMI‐Exo) and healthy controls (Normal‐Exo) were extracted. In vitro and in vivo, our study showed that circulating exosomes protected endothelial cells (HUVECs) from oxidative stress damage; meanwhile, Normal‐Exo showed better protective effects. Through the application of related inhibitors, we found that circulating exosomes shuttled between HUVECs via dynamin. Microarry analysis and qRT‐PCR of circulating exosomes showed higher expression of miR‐193a‐5p in Normal‐Exo. Our study showed that miR‐193a‐5p was the key factor on protecting endothelial cells in vitro and in vivo. Bioinformatics analyses found that activin A receptor type I (ACVR1) was the potential downstream target of miR‐193a‐5p, which was confirmed by ACVR1 expression and dual‐luciferase report. Inhibitor of ACVR1 showed similar protective effects as miR‐193a‐5p. While overexpression of ACVR1 could attenuate protective effects of miR‐193a‐5p. To sum up, these findings suggest that circulating exosomes could shuttle between cells through dynamin and deliver miR‐193a‐5p to protect endothelial cells from oxidative stress damage via ACVR1.

As emerging therapeutic factors, extracellular vesicles (EVs) offer significant potential for myocardial infarction (MI) treatment. Current delivery approaches for EVs involve either intra-myocardial or intravenous injection, where both have inherent limitations for downstream clinical applications such as secondary tissue injury and low delivery efficiency. Herein, an injection-free approach for delivering EVs onto the heart surface to treat MI is proposed. By spraying a mixture of EVs, gelatin methacryloyl (GelMA) precursors, and photoinitiators followed by visible light irradiation for 30 s, EVs are physically entrapped within the GelMA hydrogel network covering the surface of the heart, resulting in an enhanced retention rate. Moreover, EVs are gradually released from the hydrogel network through a combination of diffusion and/or enzymatic degradation of the hydrogel, and they are effectively taken up by the sprayed tissue area. More importantly, the released EVs further migrate deep into myocardium tissue, which exerts an improved therapeutic effect. In an MI-induced mice model, the group treated with EVs-laden GelMA hydrogels shows significant recovery in cardiac function after 4 weeks. The work demonstrates a new strategy for delivering EVs into cardiac tissues for MI treatment in a localized manner with high retention.

The purpose of this study is to prepare porous Zn-Ni coating with high infrared emissivity at a lower current density (1 A/cm2) by using dynamic hydrogen bubble template (DHBT) method. Three types of ceramic micro-particles (Al2O3, SiO2 and TiO2) are introduced into the electrolyte to investigate their effects on the surface morphology and infrared emissivity of Zn-Ni coating. The results show that uniform porous coatings can be obtained when these micro-particles are added into the electrolyte. The suspended micro-particles in electrolyte can prevent the H2 bubbles from rising up and escaping from the cathode, which is beneficial to the formation of porous structure, especially the insulating micro-particles, Al2O3 and SiO2. The uniform porous structure containing ceramic micro-particles is beneficial to improve infrared emissivity. In addition, the infrared emissivity of porous composite coating is also significantly dependents on the type of ceramic particles inside pores. Among the three types of micro-particles, TiO2 micro-particles have the greatest effect on the improvement of infrared emissivity which is increased from 0.83 to 0.91 when TiO2 micro-particles are deposited into the Zn-Ni coating.

Background The development of novel oral anticoagulants (NOACs) has changed the landscape of non-valvular atrial fibrillation (NVAF) management. In this study, the effectiveness and the safety of several NOACs were evaluated in a real-world setting among Asian patients with NVAF. Methods The literature search was conducted crossing different databases including Embase, MEDLINE, and the Cochrane Library from inception through March 1, 2019, for studies which included real-world perspectives comparing the individual NOACs with each other or with warfarin among Asians with NVAF. The primary outcomes were defined as stroke or systemic embolism (SSE) and major bleeding; ischemic stroke, all-cause death as well as intracranial bleeding were classified as the secondary outcomes. Results From sixteen real-world studies, a total of 312,827 Asian patients were included in this analysis. In comparison with warfarin, the utilization of apixaban, dabigatran, and rivaroxaban significantly lowered the risk of major bleeding (apixaban: HR 0.47, 95%CI 0.35–0.63; dabigatran: HR 0.59, 95%CI 0.47–0.73; rivaroxaban: HR 0.66, 95%CI 0.52–0.83) and lessened the all-cause death rate (apixaban: HR 0.29, 95%CI 0.16–0.52; dabigatran: HR 0.40, 95%CI 0.27–0.60; rivaroxaban: HR 0.42, 95%CI 0.28–0.65). Apixaban (HR 0.59; 95%CI 0.40–0.85) reduced the possibility of ischemic stroke when compared against dabigatran. Rivaroxaban showed a higher chance of causing an ischemic stroke (HR 1.61; 95%CI 1.08–2.41) and major bleeding (HR 1.39; 95%CI 1.02–1.90) than Apixaban. Conclusions Apixaban, dabigatran and rivaroxaban were more effective than warfarin on reducing the risks of stroke and haemorrhage; meanwhile, apixaban was likely to lower the risk of major bleeding comparing to rivaroxaban. Trial registration PROSPERO registry number: CRD42018086914. Electronic supplementary material The online version of this article (10.1186/s12872-019-1165-5) contains supplementary material, which is available to authorized users.

In recent years, deep learning methods bring incredible progress to the field of object detection. However, in the field of remote sensing image processing, existing methods neglect the relationship between imaging configuration and detection performance, and do not take into account the importance of detection performance feedback for improving image quality. Therefore, detection performance is limited by the passive nature of the conventional object detection framework. In order to solve the above limitations, this paper takes adaptive brightness adjustment and scale adjustment as examples, and proposes an active object detection method based on deep reinforcement learning. The goal of adaptive image attribute learning is to maximize the detection performance. With the help of active object detection and image attribute adjustment strategies, low-quality images can be converted into high-quality images, and the overall performance is improved without retraining the detector., Comment: Accepted in 25th International Conference on Pattern Recognition (ICPR), (Milan, Italy), January 2021

Cholesterol metabolism is tightly associated with colorectal cancer (CRC). Nevertheless, the clinical benefit of statins, the inhibitor of cholesterol biogenesis mevalonate (MVA) pathway, is inconclusive, possibly because of a lack of patient stratification criteria. Here, we describe that YAP-mediated zinc finger MYND-type containing 8 (ZMYND8) expression sensitizes intestinal tumors to the inhibition of the MVA pathway. We show that the oncogenic activity of YAP relies largely on ZMYND8 to enhance intracellular de novo cholesterol biogenesis. Disruption of the ZMYND8-dependent MVA pathway greatly restricts the self-renewal capacity of Lgr5+ intestinal stem cells (ISCs) and intestinal tumorigenesis. Mechanistically, ZMYND8 and SREBP2 drive the enhancer-promoter interaction to facilitate the recruitment of Mediator complex, thus upregulating MVA pathway genes. Together, our results establish that the epigenetic reader ZMYND8 endows YAP-high intestinal cancer with metabolic vulnerability.

Cardiovascular diseases (CVDs) are a major health problem worldwide, and health professionals are still actively seeking new and effective approaches for CVDs treatment. Presently, extracellular vesicles, particularly exosomes, have gained its popularity for CVDs treatment because of their function as messengers for inter‐ and extra‐cellular communications to promote cellular functions in cardiovascular system. However, as a newly developed field, researchers are still trying to fully understand the role of exosomes, and their mechanism in mediating cardiac repair process. Therefore, a comprehensive review of this topic can be timely and favourable. In this review, we summarized the basic biogenesis and characterization of exosomes and then further extended the focus on the circulating exosomes in cellular communication and stem cell‐derived exosomes in cardiac disease treatment. In addition, we covered interactions between the heart and other organs through exosomes, leading to the diagnostic characteristics of exosomes in CVDs. Future perspectives and limitations of exosomes in CVDs were also discussed with a special focus on exploring the potential delivery routes, targeting the injured tissue and engineering novel exosomes, as well as its potential as one novel target in the metabolism‐related puzzle.

Lung cancer (LC) is the leading cause of cancer-related death worldwide due to its late diagnosis and poor outcomes. As has been found for other types of tumors, there is increasing evidence that myeloid-derived suppressor cells (MDSCs) play important roles in the promotion and progression of LC. Here, we briefly introduce the definition of MDSCs and their immunosuppressive functions. We next specifically discuss the multiple roles of MDSCs in the lung tumor microenvironment, including those in tumor growth and progression mediated by inhibiting antitumor immunity, and the associations of MDSCs with a poor prognosis and increased resistance to chemotherapy and immunotherapy. Finally, we also discuss preclinical and clinical treatment strategies targeting MDSCs, which may have the potential to enhance the efficacy of immunotherapy.

A distributed energy system (DES), which combines hybrid energy storage into fully utilized renewable energies, is feasible in creating a nearly zero-energy community. Improving the design, optimization, and operation of DESs is conducive to improving system performance. Therefore, a novel DES is proposed to combine a new solar energy utilization technology and hybrid energy storage (i.e., heat storage, ice storage, and electricity storage). In addition, a new operational strategy is put forward. Subsequently, based on nearly zero-energy community and buildings, the DES configuration is optimized in relation to its environment, economy, and net interaction. Its performance and operating characteristics are compared and analysed. Then, a new indicator is proposed to evaluate the potential of the DES to achieve zero-energy. Finally, a sensitivity analysis on the carbon tax, electricity price, and equipment price is carried out. The results show that the annual carbon emissions and net interaction of the novel DES are reduced by 51.7%–73.2% and 33.5%–63.6%, respectively, compared to the reference system. Herein, the nearly zero-energy office buildings have a better zero-energy potential at 91.1%. The novel DES and corresponding multi-objective optimization method can reference a nearly zero-energy community energy supply design.

In this paper, a large number of geotechnical engineering survey data are collected in hilly and plain region along the Yangtze River in Anhui Province. Based on the statistical analysis and calculation of the experimental data of physical and mechanical properties of cohesive soils (the main quaternary soil layers in the area), the correlation between the liquidity index and water content and other physical and mechanical properties indexes are analyzed, and the fitting regression is carried out respectively. The results show that the liquidity index (IL)) and water content (w) are highly correlated with cohesion (C), compression modulus (Es), compression coefficient (α), natural density (ρ), void ratio (e), and the regression equations have high goodness of fit and good fitting effect; In addition, the fitting regression equations of water content, void ratio and natural density are compared with the theoretical calculation formula, it is found that the calculation results are close, which proves that the fitting regression equations are reliable and can be used in engineering practice.

Currently, many scholars have researched distributed energy systems (DES) from different dimensions. However, the load forecasting on both source-side and load-side, the optimal design of DES, and the multi-attribute decision making need further research. Therefore, a novel DES combining solar photovoltaic and hybrid energy storage is proposed. Combining the Monte Carlo method and improved K-means clustering is presented to predict the load on the source-side and load-side. Then, an optimal design method considering system independence and solar energy utilization scale is proposed, and the novel system is optimized. The entropy method and TOPSIS method are combined to make the multi-attribute decision on the optimization results of the system. The novel system is used to supply energy to nearly zero-energy communities (NZEC) in different scenarios. The research results show that the proposed load forecasting method can more accurately reflect the actual load demand of users. When “cost - external energy dependence - solar fraction” is taken as the target, the comprehensive energy import rate with nearly zero-energy office communities is only 36.7%, showing excellent independence. Finally, this paper can provide a method for load forecasting of NZECs, and provide certain theories for the optimization and decision-making of DESs.

The purpose of this study is to investigate the effect of sodium dodecyl sulphate (SDS) concentration on the surface morphology as well as infrared emissivity of porous Ni film prepared through the method of dynamic hydrogen bubble template (DHBT). The results indicate that the addition of SDS can enhance the hydrogen evolution reaction and increase the volume of evolving hydrogen bubbles during electrodeposition process, resulting in the increase of pore density, depth and diameter of Ni film. These factors affect the roughness greatly and the relationship between roughness and infrared emissivity has been inferred. A wide range of infrared emissivity (0.36–0.80) of porous Ni film was obtained through control of the concentration of SDS. It is concluded that the addition of SDS has a significant effect on the improvement of roughness of the porous Ni film and is beneficial for the film to obtaining high thermal emission.

In this paper, a circularly polarized retrodirective array for far field wireless power transfer (WPT) is presented. By using phase conjugation, the retransmitted wave can adjust the direction to the source automatically. A receiver is also used to show the WPT process. From the experiment, the proposed system can be a good candidate for WPT applications.

The application of hybrid energy storage to distributed energy systems can significantly improve energy efficiency and reduce the investment operating cost of the system. However, inadequate efforts are found focusing on the investigation of the integration of the two systems and optimization configuration and operation strategy of systems. Therefore, a novel distributed energy system combining hybrid energy storage was proposed, and the system optimization configuration and operation strategy of the novel system were considered simultaneously. The hybrid system contained heat storage and two power storage forms, i.e., supercapacitors and lithium battery. The influence of hybrid energy storage on distributed energy systems was fully considered. Subsequently, a two-layer collaborative optimization method for the novel system considering energy efficiency, economy, and environmental protection was presented. The novel system was applied to a nearly zero-energy community. The results indicate that the primary energy-saving and pollutant equivalent emission reduction rates of the novel system are evaluated to be 54.8% and 63.6%, respectively, under the low-pass filter operation strategy combined with the secondary feedback adjustment of the supercapacitor charge state. The system configuration and operation strategy can be optimized simultaneously by the two-layer collaborative optimization method.

Plasma exosomes derived from healthy people have been shown to be beneficial in terms of protecting against ischemia-reperfusion injury or acute myocardial infarction (AMI). However, a pathological condition may severely affect the constitution and biological activity of exosomes. In our study, we isolated plasma exosomes from healthy volunteers and convalescent AMI patients (3–7 d after onset). Compared to exosomes from healthy controls (Nor-Exo), exosomes from convalescent AMI patients (AMI-Exo) exhibited an impaired ability to repair damaged cardiomyocytes both in vitro and in vivo. miRNA sequencing and PCR analysis indicated that miR-342-3p was significantly downregulated in AMI-Exo. Moreover, miR-342-3p alleviated H2O2-induced injury and reduced apoptosis and autophagy in H9c2 cardiomyocytes, while in vivo restoration of miR-342-3p expression enhanced the reparative function of AMI-Exo. Further mechanistic studies revealed that the SOX6 and TFEB genes were two direct and functional targets of miR-342-3p. Taken together, during the early convalescent phase after AMI, dysregulated miR-342-3p in plasma exosomes might be responsible for their impaired cardioprotective potential. miR-342-3p contributed to exosome-mediated heart repair by inhibiting cardiomyocyte apoptosis and autophagy through targeting SOX6 and TFEB, respectively. Our work provided novel insights on the role of plasma exosomes in the natural process of cardiac repair after AMI and suggestions for therapy development.

Coupling electric vehicles (EV) and hybrid energy storage (HES) with the distributed energy system (DES) can improve energy-saving and emission reduction efficiency and reduce system investment operating costs. However, the system modeling, optimization design, application site, and comprehensive performance analysis of the novel DES need to be further studied. Therefore, this paper combines photovoltaic technology, HES with P2G technology, and EVs with DESs to form a DES that combines HES. Taking the annual net energy import volume and annual cost as targets, a two-layer collaborative optimization method considering both system optimal configuration and operation strategy is used. The novel system will be used to supply energy to a nearly zero-energy community. The influence of various parameters is discussed through parameter analysis. The results show that under the operation strategy in charging during the daytime, the annual net energy import and annual value cost of the novel system are 2170772 kWh and 2272786 yuan, respectively; compared with the multi-parameter collaborative optimization method, it decreased by 3.1% and 5.0%, respectively. Finally, the two-layer collaborative optimization method of this paper is also applicable to the collaborative optimization design of other complex energy systems. The proposed operation strategy is also suitable for other energy systems with source, load, and storage.

A Zn-Ni coating with both high electrical conductivity and infrared emissivity was prepared by hydrogen evolution method in order to satisfy the demand of thermal control in space. The maximum infrared emissivity of 0.91 was obtained, meanwhile the electrical resistivity is lower than 0.01 mΩ/cm. The infrared emissivity of the coating obtained from the experimental result is proportional to the projected area of pores per unit area in the coating. The addition of NH4SCN in the bath can obviously increase the projected area of pores per unit area in the coating and lead to the formation of NiO and ZnO compounds, which further increase the infrared emissivity of the coating. The porous hierarchical structure of Zn-Ni coating can further improve the infrared emissivity, and the infrared emissivity can be tuned by changing the projected area of pores in the coating. Based on the experimental results, a mathematical relationship between infrared emissivity and the projected area of pores per unit area is established. The bond strength and the mass of volatiles of the design of coatings satisfy the technical standard demanded by the satellites in space.

Despite the long history and prominence of addition polymerizations in alkene chemistry, addition polymerizations of the heavier main group analogs of alkenes are in their infancy. Herein, the detailed structural and end group analyses of polysilenes (polycarbosilanes) and polygermenes (polycarbogermanes) derived from the anionic polymerization of kinetically-stabilized silenes and germenes, respectively, are reported. The end groups were identified using ESI-TOF mass spectrometry. Careful examination of the C- H HSQC NMR spectra of both polymers confirmed the regular, alternating structure consistent with an addition polymerization with no significant amount of intramolecular rearrangement or back-biting. These results are in contrast to what has been observed during the synthesis of the analogous polyphosphenes. 13 1

Table S2. Evidence Quality Assessment in the Included Studies. (DOCX 21 kb)

The combination of a distributed energy system and multi-energy storage system has the potential to use renewable energy on a large scale and to further improve the system’s energy efficiency. Therefore, a new type of distributed energy system that combines multi-energy storage is proposed in this paper. Its novelty is that the three types of energy storage, i.e., cold, heat and electricity, are considered simultaneously, and the electric vehicle load is also included in the distributed energy system in combination with the multi-energy storage system, which allows full consideration of the effect of multi-energy storage on the distributed energy system. Three operation modes are proposed to give full play to the advantages of the new system according to the charging mode for electric vehicles. Subsequently, a two-phase collaborative optimization method for system configuration and operation optimization is proposed, and it is applied to a nearly zero energy community. The results show that the primary energy savings rate of the distributed energy system that combines multi-energy storage is 53.5% when the electric vehicle charging load is provided by the new system, which is 17.5% higher than that of the traditional distributed energy system, while the annual cost savings rate increased by only 8.3%. In addition, the hourly operating cost of the distributed energy system that combines multi-energy storage is also significantly reduced compared with the separated production system. Therefore, the method of two-phase collaborative optimization in the new system proposed in this paper can be used to realize the optimal system configuration and operation design for energy savings and consumption reduction. Finally, the new system can provide a feasible scheme for the energy supply of a nearly zero energy community in the future.

Background Thymosin alpha-1 (TA) has been reported to inhibit tumor growth as an immunomodulator. However, its mechanism of action in immunosuppressive cells is unclear. The purpose of this study was to investigate whether TA can reshape the immune microenvironment by inhibiting the function of myeloid-derived suppressor cells (MDSCs) in non-small cell lung carcinoma (NSCLC). Methods The effects of TA on peripheral blood monocytic MDSCs (M-MDSCs) in patients with NSCLC and on the apoptosis and migration of M-MDSCs were studied. A mouse subcutaneous xenograft tumor model was constructed, and the effect of TA on M-MDSC migration was evaluated. Quantitative real-time PCR, Western blotting, flow cytometry and immunohistochemistry were used to examine the mechanism by which TA affects M-MDSCs. Results TA not only promoted the apoptosis of M-MDSCs by reducing the Bcl-2/BAX ratio but also and more importantly inhibited the migration of MDSCs to the tumor microenvironment by suppressing the production of vascular endothelial growth factor (VEGF) through the downregulation of hypoxia-inducible factor (HIF)-1α in tumor cells. Conclusions TA may have a novel antitumor effect mediated by decreasing M-MDSC accumulation in the tumor microenvironment through reduced VEGF production.

The effects of glycine on the mechanism of electrodeposition of Ni–Mn alloy film prepared in ChCl–urea ionic liquid were studied in order to control the composition, microstructure and properties of the film. The cyclic voltammograms revealed that the presence of glycine in the ionic liquid can inhibit the reduction of Ni 2+ ions but promote the reduction of Mn 2+ ions in the cathodic scan. However, it promoted the dissolution of both Ni and Mn deposits in the ChCl–urea ionic liquids during the reverse scan. Glycine changed the mode of Ni–Mn film growth from Volmer–Weber mode into Stranski–Krastanov mode. The Mn content in the Ni–Mn film increased with the increase of concentration of glycine and current density. The Ni–Mn alloy film with 3.1 at.% Mn exhibited the lowest corrosion current density of 3 × 10 −7 A/cm 2 compared with other films prepared and exhibited better corrosion resistance than pure Ni film in 3.5 wt.% NaCl solution.

Nowadays, with the rapid development of the Internet of things (IoT) technology, various smart complex software systems (Smart CSS) are becoming important software paradigms for realizing the integration of human-cyber-physical ternary world. However, the characteristics of Smart CSS, including members heterogeneous, boundary openness, behavioral emergence, and continuous evolution, make the existing software analysis and design methods difficult to adapt to their development requirements. This paper proposed a data oriented analysis and design (DOAD) method for Smart CSS of IoT. It focuses on data closed loop of perception - analysis - decision - execution, including basic digital virtual objects (VO) data model design, the metadata design and standard for data exchange and catalog management, and the design of subject domain master data model. Through the implementation of DOAD Framework and its practice in the Smart CSS analysis and design of Smart City, it is demonstrated that this method can effectively help the development team to solve the existing data island and system silos problems, and improve the complexity management capability and resources reusability of the design team. In the future, we will continue to optimize it in practice by applying the DOAD method to the analysis and design of more Smart CSS of IoT.

Frequency modulated continuous wave (FMCW) radar technique has been widely used in tracking system, e.g., WiTrack System. In this paper, based on fourth order statistic, i.e., Kurtosis (KD), we propose a non-coherent CFAR detection method for FMCW indoor positioning. We develop mathematical model, investigate impacts of parameters and conduct performance evaluations. Our results show the proposed Kurtosis based detection outperforms the conventional FMCW detection technique under additive white Gaussian noise (AWGN), line-of-sight (LOS) and non-line-of-sight channel conditions. The detection probability with the proposed method can be twice better than the conventional method.

Experiments were designed to investigate the influence of controlling sintering mechanism on electrical properties of multilayer PTCR chip. During the preparation process, heating rate, sintering temperature, high-temperature holding time and cooling method were respectively regulated to prepare multilayer PTCR chip with good performance. After the process of organic casting, the casting PTCR green films were sintered at 1 260-1 280 °C for 0.5 h at reduction atmosphere, which was heated at the rate of 400 °C/h. Then selecting 300 °C/h as the cooling rate, the ceramics were oxidated at 850 °C for 1 h. The prepared multilayer PTCR chips exhibited room temperature resistivity of below 100 Ω·cm, and resistance rising rate more than 104 unit through the Curie temperature.

Electroless nickel plating on AZ91D substrate with a new and eco-friendly pretreatment process based on tuning an electrochemical homogeneous surface was investigated. The morphology, deposition process, chemical composition and microstructure of Ni–P coating were studied. It is indicated that β phases are selectively removed, producing a microstructural homogeneous surface and the subsequent uniform and compact Zn immersion layer. A defect-free and well adhesive Ni–P coating can be successfully obtained due to its uniform nucleation and growth based on such pretreatment. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests reveal that Ni–P coating could significantly improve the corrosion resistance of AZ91D substrate.

UAV main propulsion motor is required the small mass and Colliers energy density (torque density and power density), so it needs more optimal motor to achieve the purpose. The constraint condition of the main propulsion motor is a complex nonlinear continuous function, and the general Particle Swarm Optimization (PSO) algorithm is used to solve the problem when the multiple objectives are converted into different weights, and then converted to a single target for processing. And the weight of different targets is given based on experience, but the weight of the new motor is often difficult to determine the weight. In this paper, a new particle swarm optimization algorithm is proposed, which can optimize the two sub populations, and then exchange the optimal solutions of the two subgroups. Experiments show that this algorithm is applicable to main propulsion motor quality and efficiency of optimization, and the optimization results and general algorithm are compared. It is proved that the algorithm has high accuracy and fast convergence speed and is suitable for solving the similar problems.

A variety of alkyllithium (R = Me, Bu, t-Bu) reagents and potassium tert-butoxide were added to the highly reactive silene Mes2Si=CHCH2t-Bu (1) and the germene Mes2Ge=CHCH2t-Bu (4) in diethyl ether. 1,2-Addition products were obtained regioselectively and in good yield after treatment with a weak acid with no evidence for any rearrangement products and no polymerization observed. The reactivity of the silene 1 and germene 4 toward organometallic reagents is compared to previous studies of analogous silenes and germenes. (Chemical Equation Presented).

The addition of nitromethane to tetramesityldisilene and tetramesityldigermene leads to the formation of the novel 1,3,2,4,5-dioxazadisil- and digermolidine ring systems, respectively. The 1,3,2,4,5-dioxazadisilolidine isomerizes to the 1,4,2,3,5-dioxazadisilolidine ring system, whereas the 1,3,2,4,5-dioxazadigermolidine undergoes ring opening to the isomeric oxime. The preferential formation of the 1,3,2,4,5-dioxazadisilolidine, and its rearrangement to a 1,4,2,3,5-dioxazadisilolidine, provides support for the suggested reaction pathway between nitromethane and the Si(100) 2×1 reconstructed surface.

Some nanoparticles, such as quantum dots (QDs), are widely used in the biological and biomedical fields due to their unique optical properties. However, little is currently known about the interaction between these nanoparticles and biomolecules. Herein, we systemically investigated the interaction between chaperonin GroEL and water-soluble CdTe QDs based on fluorescence correlation spectroscopy (FCS), capillary electrophoresis, and fluorescence spectrometry. We observed that some water-soluble CdTe QDs were able to enter the inner cavity of GroEL and formed an inclusion complex after the activation of chaperonin GroEL with ATP. The inclusion of GroEL was size-selective to QDs and only small QDs were able to enter the inner cavity. The inclusion could suppress the fluorescence quenching of the QDs. Meanwhile, we evaluated the association constant between chaperonin GroEL and CdTe QDs by FCS. Our results further demonstrated that FCS was a very useful tool for study of the interaction of QDs and biomolecules.