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Structurally diverse silicon-incorporated indolines were synthesized via a silyl radical-triggered radical addition–translocation–cyclization (RATC) process.

Via subtle control of solution pH, the sizes of MONs have been tuned from nano- to micro-scale, accompanied by a continuous decrease in surface sensitivity, providing a simple and feasible strategy for morphological control and functional adjustment for various applications.

By confinement into a hygroscopic sponge, reversible spin-state switching and color variation has been triggered by naturally occurring humidity capture/release cycles, providing a prototype for molecular switches mediated by natural energy.

Efficient atmospheric water harvesting has been a focal point in the broad spectrum of water collection sources, to alleviate the challenges caused by water shortage.

ConspectusThe past decades have witnessed tremendous progress on radical reactions. However, in comparison with carbon, nitrogen, oxygen, and other main group element centered radicals, the synthetic chemistry of boron centered radicals was less studied, mainly due to the high electron-deficiency and instability of such 3-center-5-electron species. In the 1980s, Roberts and co-workers found that the coordination of a Lewis base (amines or phosphines) with the boron center could form 4-center-7-electron boryl radicals (Lewis base-boryl radicals, LBRs) that are found to be more stable. However, only limited synthetic applications were developed. In 2008, Curran and co-workers achieved a breakthrough with the discovery of

To clarify the impact of new transport services on consumers’ shopping behaviors and shopping-related transport emissions, a back-propagation neural network shopping channel choice model is established to estimate the number of times that consumers engage in online and offline shopping. A brick-and-mortar store choice model and travel mode choice model are developed, and a method to measure the quality of life of consumers is established to evaluate the impact of new transport services on shopping behaviors and the corresponding shopping transport emissions. The findings reveal that a new passenger transport service increases the number of times that consumers shop in brick-and-mortar stores and correspondingly shopping transport emissions; a new commodity transport service reduces the number of times that consumers shop in brick-and-mortar stores and in turn shopping transport emissions. In a scenario with both new commodity services and new passenger transport services, although online shopping is convenient, consumers are still willing to pay travel expenses for offline shopping; in a scenario with the new commodity transport service but without the new passenger transport service, the emissions from shopping-related transport are the lowest.

The construction of diversely substituted all-carbon quaternary centers has been a longstanding challenge in organic synthesis. Methods that add three alkyl substituents to a simple C(sp

This study proposes on-demand bus services for remote areas with low transit demand, incorporating travelers’ willingness to pay and values of time. To jointly optimize the on-demand service of overlapping bus routes, we construct a bi-level model. The upper-level model (UM) optimizes bus departure frequency in different time windows and ticket prices of on-demand services to minimize the total generalized cost, subject to travelers’ willingness to pay for on-demand services. The lower-level model (LM) calculates the probability of travelers choosing on-demand stops. A numerical analysis based on Meishan Island data in Ningbo indicates that with on-demand bus services, the total generalized cost incurred by buses and travelers can be reduced by 30.36% and 15.35% during rush and off-rush hours, respectively. Additionally, the waiting time at an on-demand bus stop is only 4.3 min during rush hours and 6.8 min during off-rush hours.

With the increased incidence of wine fraud, a fast and reliable method for wine certification has become a necessary prerequisite for the vigorous development of the global wine industry. In this study, a classification strategy based on three-dimensional fluorescence spectroscopy combined with chemometrics was proposed for oak-barrel and stainless steel tanks with oak chips aged wines. Principal component analysis (PCA), partial least squares analysis (PLS-DA), and Fisher discriminant analysis (FDA) were used to distinguish and evaluate the data matrix of the three-dimensional fluorescence spectra of wines. The results showed that FDA was superior to PCA and PLS-DA in classifying oak-barrel and stainless steel tanks with oak chips aged wines. As a general conclusion, three-dimensional fluorescence spectroscopy can provide valuable fingerprint information for the identification of oak-barrel and stainless steel tanks with oak chips aged wines, while the study will provide some theoretical references and standards for the quality control and quality assessment of oak-barrel aged wines.

Background Patients with developmental dysplasia of the hip (DDH) have complex proximal femoral deformities, and orthopedic surgery lacks objectivity. Expectations for surgical outcomes are often not achieved, and postoperative problems are common. Using 3D-printed technology in orthopedics offers a novel approach to precise and individualized treatment in modern orthopedics. The aim of this study was to investigate the value of the application of 3D-printed osteotomy guide plates in femoral osteotomy. The clinical indices of femoral osteotomy in children with DDH using 3D-printed osteotomy guide plates were compared with those of traditional osteotomy. Methods The clinical data of children with DDH who underwent open reduction and Salter pelvic osteotomy combined with femoral osteotomy from September 2010 to September 2020 were retrospectively collected and analyzed. Based on the inclusion and exclusion criteria, a total of 36 patients were included in the study: 16 in the guide plate group and 20 in the conventional group. Operation time (total), operation time (femoral side), X-ray fluoroscopy times (total), X-ray fluoroscopy times (femoral side) and intraoperative blood loss were analyzed and compared between the two groups. Comparison of treatment-related indicators such as postoperative neck-shaft angle, postoperative anteversion angle, hospitalization time, and hospitalization expenses is made between the two groups. The two groups of patients were evaluated at the last follow-up using the McKay clinical evaluation criteria. Results Between the two groups, there were significant differences in operation time (total), operation time (femoral side), X-ray fluoroscopy times (total), X-ray fluoroscopy times (femoral side) and intraoperative blood loss (P P > 0.05). The MacKay clinical evaluation did not significantly differ at the most recent follow-up (P > 0.05). Conclusions Children with DDH undergoing proximal femoral osteotomy using 3D-printed osteotomy guide plates benefit from a simpler surgical procedure, shorter operative time, less bleeding and less radiation exposure during surgery. This technique is of great clinical value.

Spin-center shift (SCS) is a radical process involving 1,2-radical translocation along with a two-electron ionic movement, such as elimination of an adjacent leaving group. Such a process was initially observed in some important biochemical transformations, and the unique property has also attracted considerable interest in synthetic chemistry. Experimental, kinetic, as well as computational studies have been performed, and a series of useful radical transformations have been developed and applied in organic synthesis based on SCS processes in the last 20 years. This Perspective is an overview of radical transformations involving the SCS mechanism.

Background: CAD (Coronary Artery Disease) is a complex disease that influenced by environment and genetic factors. In this study, we aim to investigate the relationship between rare nonsynonymous variants in lipid metabolism related genes and CAD in Chinese Han population. Methods: A total of 252 samples were recruited in this study, including 120 CAD cases and 132 normal health controls. Rare variants were detected via NGS based targeted sequencing. Pathogenicity prediction were performed with SIFT and Polyphen-2. Results: The present study identified 33 nonsynonymous rare variants including two novel variants located in ANGPTL4 (G47E) and SCARB1 (L233F) gene, respectively. Association analysis showed CAD patients carried more nonsynonymous variants in all mutation sets, but did not reach statistically significant. Conclusions: Targeted sequencing was a powerful tool to uncover rare variants in coronary artery disease. Clinical relevance of rare variants in CAD etiology needs to be investigated in future larger sample sizes.

Selective functionalization of C–F bonds in trifluoromethyl groups has recently received a growing interest, as it offers atom- and step-economic pathways to access highly valuable mono- and difluoroalkyl-substituted organic molecules using simple and inexpensive trifluoromethyl sources as the starting materials. In this regard, impressive progress has been made on the defluorinative functionalization reactions that proceed via radical intermediates. Nevertheless, it is still a great challenge to precisely control the defluorination process, due to the continuous decrease of the C–F bond strength after the replacement of one or two fluorine atoms with various functionalities. This review article is aimed to provide a brief overview of recently reported methods used to functionalize C–F bonds of CF3 groups via radical intermediates. An emphasis is placed on the discussion of mechanistic aspects and synthetic applications

Parcel lockers offer a service for last-mile delivery in urban logistics. To price this service, we identified its values to consignees not at receiving sites and to couriers when delivering parcels to lockers instead of consignees. A travel salesman problem (TSP) model is built to analyze the cost change of last-mile delivery corresponding to the availability of consignees at designated receiving sites. Based on cost evaluation, fees that consignees and couriers should pay respectively are determined based on beneficiary-pay principle. The results of our empirical analyses show that the value of the locker service varies with the terms of express delivery and the availability uncertainty of whether consignees are present at the designated receiving sites, which provides a fundamental pricing basis for locker service providers to charge the couriers or the consignees.

Remifentanil combined with sevoflurane is a standard protocol for obstetric general anesthesia (GA).In this study, we performed a randomized clinical trial to evaluate whether remifentanil has an effect on the median effective concentration (EC50) of sevoflurane and compare anesthetic outcomes of them in cesarean section with Supreme™ laryngeal mask airway (SLMA) under narcotrend monitoring. Ninety parturients with singleton births undergoing elective cesarean delivery (CD) with initial inhaled 1.0 minimum alveolar concentration (MAC) sevoflurane for anesthesia maintenance were assigned to three groups randomly and evenly: Group A (0.05 µg·kg-1·min-1 remifentanil combined with sevoflurane), Group B (0.1 µg·kg-1·min-1 remifentanil combined with sevoflurane), and Group C (normal saline combined with sevoflurane). Narcotrend was used to monitor the depth of anesthesia during the operation, with the level of anesthesia depth controlled within the D-E stage. The EC50 of sevoflurane was determined by Dixon's sequential method. The Narcotrend index, amount of bleeding, neonatal Apgar score, and corresponding treatment measures in the three groups were recorded.The results showed that the estimated EC50 of sevoflurane for obstetric GA was 0.80 MAC (95% CI: 0.63-0.95 MAC) in group A, 0.82 MAC (95% CI: 0.63-0.96 MAC) in group B, and 0.80 MAC (95% CI: 0.63-0.95 MAC) in group C. There was no statistically significant difference in the estimated EC50 of sevoflurane, time to wakefulness, Apgar score, amount of intraoperative bleeding, and postoperative bleeding within 24 hours between the three groups (all P0.05).The addition of remifentanil at 0.05-0.1 µg·kg-1·min-1 did not change the EC50 of sevoflurane and anesthetic quality. The concentration of inhaled anesthetics can be minimized with Narcotrend monitoring.Chinese Clinical Trial Registry ChiCTR2000034512.

A boundary element method (BEM) is implemented and applied to compute the band structures of phononic crystals taking account of three different kinds of imperfect interface layers. By using the Bloch theorem and the interface conditions the eigenvalue equations related to the wave vector are derived. The influences of the spring-interface model, mass-interface model and spring-mass-interface model on the dispersion curves and the band-gaps are investigated by comparing with that of the perfect interfaces. For different interface models, the effects of various interface parameters and mass density ratios on the lower edge, upper edge and width of the first complete band-gap are analyzed and discussed. It will be shown that a weak interface imperfection would not affect the dispersion curves, but a relatively strong interface imperfection may significantly affect the band structures of phononic crystals and it cannot be ignored. Moreover, the three interface models have different influences on the wave propagation and band-gap characteristics of the phononic crystals.

Background The shortening length of the lower extremity after the proximal femoral osteotomy is an important issue to be considered in preoperative planning of developmental dysplasia of the hip (DDH) in children. There is still a lack of research on shortening the length of the lower extremities in different proximal femoral osteotomy varus styles. We aimed to verify the relationship between the shortening length after “point-to-face” and “face-to-face” varus osteotomy and proposed a formula for calculating the difference in shortening length and verified its feasibility. Methods Fifty-five children with unilateral DDH were enrolled. The preoperative hip CT data were imported into mimics 21, 3-Matic 10 (Materialise, Leuven, Belgium) for femoral reconstruction and simulated osteotomy, and the difference (t) was calculated by directly measuring the length of the proximal femur after osteotomy. d* sinθ was measured in a three-dimensional environment to calculate the difference in femoral shortening length between the two osteotomy methods (t'). Results The results of the direct measurement method and the formula measurement method are shown in the table; the differences in the results of the femoral shortening length difference were not statistically significant (P > 0.05). The limits of agreement (95%) of the difference values using Bland–Altman analysis were between − 0.50 and 0.46 mm, with a mean of − 0.02 mm, indicating a high agreement between the two methods. r = 0.99 (P Conclusions The derived formula can accurately calculate the difference in the shortening length of the proximal femur after “point-to-face” and “face-to-face” varus osteotomy in children with DDH, which is suitable for clinical application.

The uncertainty of noise statistics in dynamic systems is one of the most important issues in engineering applications, and significantly affects the performance of state estimation. The optimal Bayesian Kalman filter (OBKF) is an important approach to solve this problem, as it is optimal over the posterior distribution of unknown noise parameters. However, it is not suitable for online estimation because the posterior distribution of unknown noise parameters at each time is derived from its prior distribution by incorporating the whole measurement sequence, which is computationally expensive. Additionally, when the system is subjected to large disturbances, its response is slow and the estimation accuracy deteriorates. To solve the problem, we improve the OBKF mainly in two aspects. The first is the calculation of the posterior distribution of unknown noise parameters. We derive it from the posterior distribution at a previous time rather than the prior distribution at the initial time. Instead of the whole measurement sequence, only the nearest fixed number of measurements are used to update the posterior distribution of unknown noise parameters. Using the sliding window technique reduces the computational complexity of the OBKF and enhances its robustness to jump noise. The second aspect is the estimation of unknown noise parameters. The posterior distribution of an unknown noise parameter is represented by a large number of samples by the Markov chain Monte Carlo approach. In the OBKF, all samples are equivalent and the noise parameter is estimated by averaging the samples. In our approach, the weights of samples, which are proportional to their likelihood function values, are taken into account to improve the estimation accuracy of the noise parameter. Finally, simulation results show the effectiveness of the proposed method.

Sparse reward long horizon task is a major challenge for deep reinforcement learning algorithm. One of the key barriers is data-inefficiency. Even in the simulation environment, it usually takes weeks to training the agent. In this study, a data-efficiency training framework is proposed, where a curriculum learning is design for the agent in the simulation scenario. Different distributions of the initial state are set for the agent to get more informative reward during the whole training process. A fine-tuning of the parameters in the output layer of the neural network for value function is conduct to bridge the gap between sim-to-real. An experiment of UAV maneuver control is conducted in the proposed training framework to verify the method more efficient. We demonstrate that data-efficiency is different for the same data in different training stages.

Environmental pollution and resistance in animals are major concerns for the application of synthetic pesticides. Diallyl trisulfide (DAT), an active compound in garlic essential oil, is a novel tool for active and safe control of agricultural insect pests. In this study, we analysed the effects of DAT (0.01 μL/L) on the protein content in male reproductive tissues (accessory glands, ejaculatory ducts, and testis), and juvenile hormone (JH) and ecdysone titres in a highly detrimental pest of stored products, Sitotroga cerealella. Evaluation of the expression profile of JH and ecdysone pathway-related genes in various tissues indicated that the accessory gland protein and ecdysone titres were markedly decreased after DAT fumigation, whereas the testis protein content and JH titre were increased. However, the protein content of the ejaculatory ducts remained unchanged between the treated and control groups. Further investigation revealed that DAT disrupted the mRNA expression of key enzymes involved in JH and ecdysone pathways. While increased mRNA levels of juvenile hormone acid O-methyltransferase (JHMAT) and Kruppel homologue 1 (Kr-h1) were observed after 4 and 7 h of DAT fumigation, the levels of juvenile hormone epoxide hydrolase (JHEH) were substantially reduced 3 h post-fumigation. mRNA levels of the ecdysone-responsive gene, FTZF1, and cytochrome P450 enzyme, CYP315A1, were notably decreased at 7 h and 4 h, respectively, post-fumigation, whereas CYP314A1 and CYP302A1 mRNA levels decreased after 3 h and 4 h, respectively. While DAT fumigation disrupted sperm number in the testis, ejaculatory ducts, and seminal vesicles, topical application of the 20-hydroxyecdysone (20E) analogue also lowered sperm number in the ejaculatory ducts. Topical application of methoprene, a JH analogue, increased the protein content in the testes, but not in the accessory glands or ejaculatory ducts. However, the survival rate was not affected by the topical application of methoprene or 20E. These data suggest that DAT regulates JH and ecdysone via its molecular pathway genes and modulates endocrine secretion during the male reproductive process.

The classical Kalman filter is a very important state estimation approach, which has been widely used in many engineering applications. The Kalman filter is optimal for linear dynamic systems with independent Gaussian noises. However, the independence and Gaussian assumptions may not be satisfied in practice. On the one hand, modeling physical systems usually results in discrete-time state-space models with correlated process and measurement noises. On the other hand, the noise is non-Gaussian when the system is disturbed by heavy-tailed noise. In this case, the performance of the Kalman filter will deteriorate, or even diverge. This paper is devoted to addressing the state estimation problem of linear dynamic systems with high-order autoregressive moving average (ARMA) non-Gaussian noise. First, a triplet Markov model is introduced to model the system with high-order ARMA noise, since this model relaxes the independence assumption of the hidden Markov model. Then, a new filter is derived based on correntropy, instead of the commonly used minimum mean square error (MMSE), to deal with non-Gaussian noise. Unlike the MMSE, which uses only second-order statistics of error, correntropy can capture second-order and higher-order statistics. Finally, simulation results verify the effectiveness of the proposed algorithm.

The present study is concerned with the buckling, vibration and sound transmission characteristics of the simply supported sandwich plate with trapezoidal corrugated core in thermal environment bas...

Lei Yang, Song Xue, Mingjun Du, Feng Lian Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, People’s Republic of ChinaCorrespondence: Feng Lian Email dr.lianfeng@hotmail.comIntroduction: The reprogramming of induced cardiomyocytes (iCMs) is of particular significance in regenerative medicine; however, it remains a great challenge to fabricate an efficient and safe gene delivery system to induce reprogramming of iCMs for therapeutic applications in heart injury. Here, we report branched polyethyleneimine (BP) coated nitrogen-enriched carbon dots (BP-NCDs) as highly efficient nanocarriers loaded with microRNAs-combo (BP-NCDs/MC) for cardiac reprogramming.Methods: The BP-NCDs nanocarriers were prepared and characterized by several analytical techniques.Results: The BP-NCDs nanocarriers showed good microRNAs-combo binding affinity, negligible cytotoxicity, and long-term microRNAs expression. Importantly, BP-NCDs/MC nanocomplexes led to the efficient direct reprogramming of fibroblasts into iCMs without genomic integration and resulting in effective recovery of cardiac function after myocardial infarction (MI).Conclusion: This study offers a novel strategy to provide safe and effective microRNAs-delivery nanoplatforms based on carbon dots for promising cardiac regeneration and disease therapy.Keywords: nitrogen-enriched carbon dots, branched polyethyleneimine, microRNAs, direct reprogramming, induced cardiomyocytes

To compete with online e-commerce, traditional retailing is implementing a new retail mode that combines online sales with physical stores, which may change the channel, transport mode and logistics cost of retail commodities from manufacturers to end consumers. In this context, it is necessary for physical retailers to relocate their shopping centers in order to maximize profits. This paper develops a location optimization model for physical shopping centers based on consumer shopping choices (platform choices and store choices), carbon tax policy and the economic scale of transport under the new retail mode. This model is applied to optimize the number and scale of physical shopping centers and corresponding locations with the objective of maximizing the retail profit under the new retail mode. The results show that under the new retail mode, the number of shopping centers, the scale of an individual physical store and the total retail logistics cost decrease, while the retail profit increases. This work lays a theoretical basis for retailers to build online and offline retail systems and rationally determines the spatial distribution of shopping centers in a city.