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The robust unit commitment (UC) is of paramount importance for achieving reliable operations considering the uncertainty of renewable realizations. The typical affine decision rule method and the robust feasible region method may achieve uneconomic dispatches as the dispatch decisions just rely on the current-stage information. Through approximating the future cost-to-go functions, the dual dynamic programming based methods have been shown adaptive to the multistage robust optimization problems, while suffering from high computational complexity. Thus, we propose the robust approximate dynamic programming (RADP) method to promote the computational speed and the economic performance for large-scale robust UC problems. RADP initializes the candidate points for guaranteeing the feasibility of upper bounding the value functions, solves the alternating calculation based bilinear programming to obtain the worst cases, and combines the primal and dual updates for the two-phase robust UC decision-making problem to achieve fast convergence. The finite termination guarantee of the RADP method is verified by the analyses for the multistage robust optimization problems with achieving suboptimal solutions. Numerical tests on 118-bus and 2383-bus transmission systems have demonstrated that RADP can approach the suboptimal economic performance at significantly improved computational efficiency. Note to Practitioners—This paper was motivated by solving the large-scale robust UC problem embedded with the multistage economic dispatch with improved computational and economical performance. Compared to the existing methods, this work suggests a RADP-based approach, which is inspired by the robust dual dynamic programming (RDDP) scheme. The proposed RADP owns lower computational complexity when compared with RDDP. As the problem in this work is formulated in a general form, the proposed RADP can be applied to other robust optimization problems such as the inventory management problem with uncertain demands. To apply the method to large-scale decision-making problems, one needs to solve linear programming problems to obtain the finite upper/lower bounds first, and then initialize the upper-bound points based on the feasible region limits of the decision variables. Conduct the forward pass to generate the candidate points and the backward pass to refine the cost-to-go functions. If the application problems have discrete decision variables as in the two-phase UC, one can solve the nonanticipativity constrained problem to obtain discrete solutions before doing the RADP scheme. The analyses and numerical experiments suggest that this approach can achieve suboptimal solutions. In future research, we will address the accelerated multistage robust decision-making with achieving optimal solutions.

A ligand-controlled regiodivergent and enantioselective ring expansion of benzosilacyclobutenes with internal naphthyl alkynes has been achieved by adjusting the ligand cavity size. The ligand (S)-8H-binaphthyl phosphoramidite, featuring small methyl groups on its arms, provides a spacious cavity that favors sterically demanding Si–Csp3ring expansion, predominantly yielding axially chiral (S)-1-silacyclohexenyl arenes. In contrast, the ligand (R)-spiro phosphoramidite, with bulky t-Bu groups on its arms, offers a compact cavity that facilitates less sterically demanding Si–Csp2ring expansion, leading primarily to axially chiral (S)-2-silacyclohexenyl arenes. Density functional theory calculations delineate distinct mechanistic pathways for each ring expansion route and elucidate their regio- and enantioselectivity.

The impedance-based interoperability evaluation is a commonly used testing method to guarantee interconnection and interoperability among different wireless charging devices. Its advantage lies in using reference devices to avoid extensive cross testing. However, the manufacturing tolerances and the parameter drift of the reference devices often result in deviations of the tested values from the standard, increasing misjudgment rates. This incurs in the need of determining boundaries and tolerance zones to characterize the uncertainty of test results, which still lacks clear methods. To solve this problem, this letter introduces a characterization model for the correlation between port impedance and interoperability according to volt–ampere requirements for coils and power electronics. Then, a method for determining tolerance zones through error transfer functions is proposed. Finally, the effectiveness of the proposed tolerance zones in identifying the uncertainty propagation from parameter drift to test results is verified by the designed experiment. Given a manufacturing tolerance or parameter drift of ±2%, the interoperability evaluation indicated by the proposed tolerance zones can provide a more precise classification assessment for 20% of interoperable devices.

Sigma-1 receptor (s1R) is an intracellular protein implicated in a spectrum of neurodegenerative conditions, notably Alzheimer’s disease (AD). Positron emission tomography (PET) imaging of brain s1R could provide a powerful tool for better understanding the underlying pathomechanism of s1R in AD. In this study, we successfully developed a 18F-labeled s1R radiotracer [18F]CNY-05 via an innovative ruthenium (Ru)-mediated 18F-deoxyfluorination method. [18F]CNY-05 exhibited preferable brain uptake, high specific binding, and slightly reversible pharmacokinetics within the PET scanning time window. PET imaging of [18F]CNY-05 in nonhuman primates (NHP) indicated brain permeability, metabolic stability, and safety. Moreover, autoradiography and PET studies of [18F]CNY-05 in the AD mouse model found a significantly decreased brain uptake compared to that in wild-type mice. Collectively, we have provided a novel 18F-radiolabeled s1R PET probe, which enables visualizing brain s1R in health and neurological diseases.

Unraveling the mechanism of chirality transfer across length scales is crucial to the rational development of functional materials with hierarchical chirality. The key obstacle is the lack of structural information, especially at the mesoscopic level. We report herein the structural identification of helical covalent organic frameworks (heliCOFs) with hierarchical chirality, which integrate molecular chirality, channel chirality, and morphology chirality into one crystalline entity. Specifically, benefiting from the highly ordered structure of heliCOFs, the existence of chiral channels at the mesoscopic level has been confirmed by electron crystallography, and the handedness of these chiral channels has been directly determined through the stereopair imaging technique. Accordingly, the chirality transfer in heliCOFs from microscopic to macroscopic levels could be rationalized with a layer-rotating model that has been supported by both crystal structure analysis and theoretical calculations. Observation of chiral channels in heliCOFs not only provides unprecedented data for the understanding of the chirality transfer process but also sheds new light on the rational construction of highly ordered polymeric materials with hierarchical chirality.

ABSTRACTThe COVID-19 pandemic has had a profound impact worldwide and continues to spread due to various mutations of the virus. Many governmental and nonprofit agencies at different levels have quickly developed COVID-19 dashboards to disseminate information on the pandemic to the public. However, most of these systems have mainly distributed “plain” information (e.g. cases, death counts, vaccination), and rarely provided insights that can be gained from spatiotemporal analyses, such as the detection of emerging clusters. The results from these analyses hold tremendous potential for health policymakers as they try to identify ways to slow down transmission. We present a web-based geographic framework to detect and visualize space-time clusters of COVID-19. Our tightly coupled framework integrates the prospective space-time scan statistics and local indicators of spatial association (LISA) with novel 2D and 3D interactive visuals in a cyber environment (http://159.223.164.41/app/). We illustrate the applicability of our approach using COVID-19 data for the continental US. Our framework is portable to other regions that may experience infectious diseases but is also flexible to handle data of different spatial and temporal granularities. This paper fits within an effort to integrate space-time analytics for the monitoring of infectious diseases in web environment, ultimately improving health surveillance systems.

Asymmetric catalysis enables the synthesis of optically active compounds, often requiring the differentiation between two substituents on prochiral substrates1. Despite decades of development of mainly noble metal catalysts, achieving differentiation between substituents with similar steric and electronic properties remains a notable challenge2,3. Here we introduce a class of Earth-abundant manganese catalysts for the asymmetric hydrogenation of dialkyl ketimines to give a range of chiral amine products. These catalysts distinguish between pairs of minimally differentiated alkyl groups bound to the ketimine, such as methyl and ethyl, and even subtler distinctions, such as ethyl and n-propyl. The degree of enantioselectivity can be adjusted by modifying the components of the chiral manganese catalyst. This reaction demonstrates a wide substrate scope and achieves a turnover number of up to 107,800. Our mechanistic studies indicate that exceptional stereoselectivity arises from the modular assembly of confined chiral catalysts and cooperative non-covalent interactions between the catalyst and the substrate.

Aiming at achieving wideband and filtering performance with high out-of-band suppression, this article presents a method of designing a millimeter-wave (mmWave) filtering magnetoelectric (ME) dipole antenna. Different from most previous works, antiphase electric and magnetic currents are generated simultaneously by parasitic symmetric split rings and suspended straight strips, respectively, canceling the radiation of the ME dipole in the stopband. Furthermore, the bifunctional $\Pi $ -shaped feeding probe excites the ME dipole by capacitive coupling to realize a wide bandwidth and generates an out-of-band bandstop resonance mode to enhance the filtering performance. Therefore, multiple radiation nulls can be generated to achieve a high roll-off rate and wide stopband. The proposed antenna realizes a suppression level of over 33 dB in the stopband and an in-band efficiency of over 95%. The measured results show that the implemented $1\times 4$ filtering array has a wide bandwidth of 21.6–31.5 GHz (37.3%). The measured average gain is about 12.9 dBi, and the out-of-band rejection level exceeds 26 dB in the stopband.

Catalytic cleavage of C=C double bonds in alkenes is highly important to convert feedstocks into high-value compounds. However, these approaches are mainly limited to oxidative cleavage of alkenes with excess oxidants and redox-neutral alkene metathesis. In contrast, reductive C=C double bond cleavage and functionalization have not been reported. Herein, we report a novel visible-light photoredox-catalyzed carboxylation of styrenes with CO2viareductive C=C double bond cleavage. The use of dicyclohexylmethylamine as scission reagent is the key to the success. Different from previous homologation reactions with CO2, this protocol enabled exchange of the carbon of styrenes with CO2, affording important aryl acetic acids viaC=C double bond cleavage. Moreover, preliminary mechanistic investigation and DFT calculations shed light on the reaction mechanism, disclosing aminomethyl-carboxylation intermediate, benzylic radicals and carbanions as key intermediates in the reaction.

Tongxie Yaofang (TXYF) has therapeutic effect on the ulcerative colitis (UC) with liver depression and spleen deficiency syndrome. This study investigated the changes in the gut microbiota of UC rats treated with TXYF. Wistar rats were divided into three groups: Control, dinitrobenzene sulfonic acid (DNBS)-colitis, and DNBS + TXYF (n = 8 per group). UC model was constructed via intrarectally injection of DNBS (25 mg DNBS and 0.25 mL 50% ethanol); rats in DNBS + TXYF group were administered with TXYF (20.8 g/kg) for 21 days. Physiological parameters were measured. Five samples from each group were selected for metagenomic analysis. TXYF treatment significantly reduced disease activity index, colon mucosal damage index, and tumor necrosis factor-alpha level. TXYF treatment prevented DNBS-induced dysregulation of gut microbial communities. Compared with DNBS-colitis group, the abundance of Firmicutesincreased significantly and that of Bacteroidetesand Proteobacteriadecreased in DNBS + TXYF group. Pathways such as protein processing in the endoplasmic reticulum pathway was enriched in the DNBS-colitis group, whereas it was decreased in the DNBS + TXYF group. Thus, TXYF treatment could effectively restore the dysregulation of intestinal flora induced by UC.

This paper concerns with efficient projection onto the ordered weighted ℓ1norm ball, which is equivalent to the problem of finding projector onto the intersection of the monotone nonnegative cone and an affine subspace. Based on Lagrangian relaxation and secant approximation method, we propose an easily implementable yet efficient algorithm to solve the projection problem which is proved to terminate after a finite number of iterations. Furthermore, we design efficient implementations for our algorithm and compare it with a semismooth Newton (Ssn) algorithm and a root-finding (Root-F) algorithm. Numerical results on a diversity of test problems show that our algorithm is superior than Ssnand Root-F.

Prior to the generation of hematopoietic stem cells (HSCs) from the hemogenic endothelial cells (HECs) mainly in the dorsal aorta in midgestational mouse embryos, multiple hematopoietic progenitors including erythro-myeloid progenitors and lymphoid progenitors are generated from yolk sac HECs. These HSC-independent hematopoietic progenitors have recently been identified as major contributors to functional blood cell production until birth. However, little is known about yolk sac HECs. Here, combining integrative analyses of multiple single-cell RNA-sequencing datasets and functional assays, we reveal that Neurl3-EGFP, in addition to marking the continuum throughout the ontogeny of HSCs from HECs, can also serve as a single enrichment marker for yolk sac HECs. Moreover, while yolk sac HECs have much weaker arterial characteristics than either arterial endothelial cells in the yolk sac or HECs within the embryo proper, the lymphoid potential of yolk sac HECs is largely confined to the arterial-biased subpopulation featured by the Unc5bexpression. Interestingly, the B lymphoid potential of hematopoietic progenitors, but not for myeloid potentials, is exclusively detected in Neurl3-negative subpopulations in midgestational embryos. Taken together, these findings enhance our understanding of blood birth from yolk sac HECs and provide theoretical basis and candidate reporters for monitoring step-wise hematopoietic differentiation.

Bridged frameworks are of high chemical and biological significance, being ubiquitous in pharmaceutical molecules and natural products. Specific structures are usually preformed to build these rigid segments at the middle or late stage in the synthesis of polycyclic molecules, resulting in decreased synthetic efficiency and target-specific syntheses. As a logically distinct synthetic strategy, we constructed an allene/ketone-equipped morphan core at the outset through an enantioselective α-allenylation of ketones. Experimental and theoretical results revealed that the high reactivity and enantioselectivity of this reaction are attributed to the cooperative effects of the organocatalyst and metal catalyst. The bridged backbone generated was employed as a structural platform to guide and facilitate the assembly of up to five fusing rings, and the allene and ketone groups thereon were used to precisely install various functionalities at C16 and C20 at the late stage, leading to a concise, collective total synthesis of nine strychnan alkaloids.

Difunctionalizing carboxylation of alkynes with CO2is a sustainable and important strategy to generate valuable acrylate derivatives from both readily available starting materials. Such protocols, however, always suffer from the use of excess metallic reagents and transition metal residue. Herein, we report the first thio-carboxylation of alkynes with thiophenols and CO2, which is a visible-light-driven and transition metal-free process. In contrast to previous carboxylations of alkynes viatwo-electron activation of CO2, mechanistic and computational investigations suggest that the single-electron activation of CO2is involved in the thio-carboxylation, rendering unique β-carboxylation. The following cyclizing acylation affords important thiochromones efficiently. Moreover, the one-pot method features mild reaction conditions (room temperature, 1 atmosphere of CO2), high chemo- and regio-selectivity, easy scalability and facile derivatization of products to bioactive compounds.

Over the past decades, many efficient methodologies have been developed that allow for the enantioselective synthesis of chiral sulfinyl compounds. However, the enantioselective deoxygenation of hexavalent sulfones for the formation of chiral sulfinyl compounds still remains one of the major challenges in the fields of asymmetric synthesis and organosulfur chemistry. Here we have demonstrated that a synergistic combination of organocatalysis and the incorporation of a cyano group into the sulfone generates a chiral sulfinic species as an active intermediate. A wide range of chiral sulfinates with high enantioselectivities could then be acquired using alcohols as nucleophiles, and the subsequent transformations allowed the collective preparation of a variety of chiral sulfinyl compounds. Density functional theory calculations revealed that the catalytic cycle involves a quinuclidine-assisted stepwise 1,2-cyano group transfer, base-assisted intermolecular substitution with alcohol and regeneration of the active catalyst. The enantioselectivity was determined by the cyano migration step.

AbstractPacked beds play an important role in many engineering fields, with their applications in nuclear energy being driven by the development of next-generation reactors utilizing pebble fuel. The random nature of a packed pebble bed creates a flow field that is complex and difficult to predict. Porous media models are an attractive option for modeling pebble-bed reactors (PBRs), as they provide intermediate fidelity results and are computationally efficient. Porous media models, however, rely on the use of correlations to estimate the effect of complicated flow features on the pressure drop and heat transfer in the system. Existing correlations were developed to predict the average behavior of the bed, but they are inaccurate in the near-wall region where the presence of the wall affects the pebble packing.This work aims to investigate the accuracy of a porous media model using the Kerntechnischer Ausschuss (KTA) correlation, the most common pressure drop correlation for PBRs compared to the high-fidelity large eddy simulation (LES). A bed of 1568 pebbles is investigated at Reynolds numbers from 625 to 10 000. The bed is divided into five concentric subdomains to compare the average velocity, friction losses, and form losses between the porous media and LES codes. The comparison between the LES simulation and the KTA correlation revealed that the KTA correlation largely underpredicts the form losses in the near-wall region, leading to an overprediction of the velocity near the wall by nearly 30%. An investigation of the form losses across the range of Reynolds numbers in the LES results provided additional insight into how the KTA correlation may be improved to better predict these spatial effects in a pebble bed. These data suggest that the form coefficient near the wall must be increased by 48% while decreasing the form coefficient of the inner bulk region of the bed by 15%. The implementation of these improvements to the KTA correlation in a porous media model produced a radial velocity profile that saw significantly improved agreement with the LES results.

The multistage economic dispatch solution is of paramount importance for achieving the optimal unit commitment and the optimal decentralized decision-making in smart grid operations. Through the approximations of the optimal expected cost-to-go functions, the stochastic dual dynamic programming (SDDP) has been shown effective to obtain the optimum for the multistage stochastic programming (SP) problem, while without finite termination guarantee. Thus, we propose a fast stochastic dual dynamic programming (FSDDP) method to accelerate the convergence rate of the SDDP, including updating the candidate points based on the case with the maximum difference between the upper and lower bounds of the optimal value functions, adding a backward-forward-backward inner scheme in the backward pass, and initializing the bounds with finite constant values. We can verify that the FSDDP method enjoys a nice property with a finite convergence guarantee for the multistage SP problems. Numerical tests on 4-, 33-, 34-, 69-, 118- and 123-bus distribution systems have demonstrated that FSDDP can approach the optimal economic performance at significantly improved computational efficiency.

The use of the flipped classroom approach in chemistry courses has rapidly increased over the past decade, and it appears that this type of learning environment will play an essential role in improving student success. However, it's crucial to note that the majority of these studies were carried out in higher education environments. There hasn’t been much research comparing flipped to traditional classrooms in K-12 institutions. The majority of comparisons between flipped and non-flipped groups were taught by different teachers, and typically conducted over a brief period of time, often a few weeks. The purpose of this study is to examine the impacts of the flipped classroom on student performance and problem solving skills in chemistry courses. A two-stage experiment was conducted in a secondary school in the Northwestern part of China with the flipped classroom group including 46 students, 20 males and 26 females and the non-flipped classroom group consisting of 50 students, 30 males and 20 females. Both groups were taught by the same chemistry teacher with eight years of teaching experience. Independent t-tests showed that the flipped classroom significantly improved student academic performance compared to the non-flipped classroom, and this effect lasted for at least one year. The study also found that flipped classrooms have a more progressive impact on students’ problem solving skills, which always take a long teaching period. Meanwhile, the research findings revealed that most students preferred or strongly preferred the flipped classroom approach after they experienced it. However, as the duration of the teaching experiment grows, students’ attitudes toward the flipped classroom approach tend to polarize.

Human spermatogenesis is a highly ordered process; however, the roles of DNA methylation and chromatin accessibility in this process remain largely unknown. Here by simultaneously investigating the chromatin accessibility, DNA methylome and transcriptome landscapes using the modified single-cell chromatin overall omic-scale landscape sequencing approach, we revealed that the transcriptional changes throughout human spermatogenesis were correlated with chromatin accessibility changes. In particular, we identified a set of transcription factors and ciselements with potential functions. A round of DNA demethylation was uncovered upon meiosis initiation in human spermatogenesis, which was associated with male meiotic recombination and conserved between human and mouse. Aberrant DNA hypermethylation could be detected in leptotene spermatocytes of certain nonobstructive azoospermia patients. Functionally, the intervention of DNA demethylation affected male meiotic recombination and fertility. Our work provides multi-omics landscapes of human spermatogenesis at single-cell resolution and offers insights into the association between DNA demethylation and male meiotic recombination.

We describe a novel triazole-phosphine Pd(II) (TPP) complex-catalyzed dehydrogenation reaction of alcohols or amines by using iodobenzene as the oxidant, in which a unique butterfly TPPdimer is first prepared via a three-component reaction of 1,2,3-triazole, P(Cy)3, and PdCl2and the competitive cross-coupling reaction of iodobenzene with alcohols or amines could be avoided under TPPcatalysis. In particular, the primary alcohols and imines can be further oxidized into acids or nitriles in a tunable manner, respectively. Preliminary mechanistic results by density functional theory calculation suggest that this reaction follows the Pd(II)–Pd(IV) catalytic pathway and the process of TPP-catalyzed oxidation dehydrogenation of alcohol or amine to form unsaturated bonds and Pd(II)–H species generated before the oxidative addition of TPPwith iodobenzene, thereby avoiding competitive cross-coupling.

Artificial intelligence (AI) solutions that automatically extract information from digital histology images have shown great promise for improving pathological diagnosis. Prior to routine use, it is important to evaluate their predictive performance and obtain regulatory approval. This assessment requires appropriate test datasets. However, compiling such datasets is challenging and specific recommendations are missing. A committee of various stakeholders, including commercial AI developers, pathologists, and researchers, discussed key aspects and conducted extensive literature reviews on test datasets in pathology. Here, we summarize the results and derive general recommendations on compiling test datasets. We address several questions: Which and how many images are needed? How to deal with low-prevalence subsets? How can potential bias be detected? How should datasets be reported? What are the regulatory requirements in different countries? The recommendations are intended to help AI developers demonstrate the utility of their products and to help pathologists and regulatory agencies verify reported performance measures. Further research is needed to formulate criteria for sufficiently representative test datasets so that AI solutions can operate with less user intervention and better support diagnostic workflows in the future.

Multistage stochastic economic dispatch (ED) solutions play a crucial role in obtaining reliable and cost-effective operations. The stochastic dual dynamic programming (SDDP) has been proposed to achieve optimal solutions for multistage stochastic programming (SP) problems under the probabilistic convergence rate. The fast SDDP (FSDDP) method can guarantee finite convergence by solving bilevel problems for generating deterministic updates while suffering from the high computational complexity of large-scale decision-making systems. Thus, we leverage the recent advances in the primal–dual reformulation method of solving bilevel problems, which allows for first-order gradient descent/ascent (GDA) updates. Based on the primal–dual bilevel optimizer (PDBO), we propose the gradient-accelerated SDDP (GA-SDDP) for solving stochastic ED problems. Taking advantage of the finite termination of PDBO for solving bilevel problems, the finite convergence of GA-SDDP is verified by the analysis. Numerical tests on the IEEE 33-bus, 69-bus, and 123-bus systems have shown that GA-SDDP can achieve finite termination compared to SDDP and improved computational performance over FSDDP.

Improving the power and efficiency of 9xx-nm broad-area laser diodes has a great help in reducing the cost of laser systems and expanding applications. This letter presents an optimized epitaxial structure with high power and conversion efficiency. Laser diodes with 230 $\mu \text{m}$ emitter width and 5 mm cavity length deliver continuous-wave output power up to 48.5 W at 48 A, 30 °C, the highest power reported for 9xx-nm single emitter lasers so far. The slope efficiency is as high as 1.23 W/A due to a low internal optical loss of 0.31 cm−1 and a high internal efficiency of 96%. The maximum power conversion efficiency reaches 72.6% at 15.3 W and 67.3% at the operating power of 30 W under a heatsink temperature of 25 °C. Life test results show no failure in 1000 hours for 55 laser diodes.

High‐risk papillary thyroid carcinoma (PTC) patients with BRAFmutation have lymph node and distant metastases and poor prognosis. Therefore, this study aims to develop a targeted ultrasound contrast agent for the BRAFV600Emutation to screen high‐risk PTC at early stage. The targeted lipid nanobubbles carrying BRAFV600Eantibody were prepared using thin film hydration‐sonication and avidin‐biotin binding methods. The physicochemical properties and stability of the targeted nanobubbles were detected by transmission electron microscopy, atomic force microscopy, and confocal laser scanning microscopy. The target binding abilities of the targeted nanobubbles in the PTC cells (B‐CPAP) overexpressed mutant BRAFV600Ewere evaluated by immunofluorescence staining, quantitative real‐time polymerase chain reaction, western blot, and fluorescence microscopy. After PTC tumor models overexpressed mutant BRAFV600Ewere established, the enhanced images of targeted lipid nanobubbles and untargeted lipid nanobubbles on PTC tumors in nude mice were observed using contrast‐enhanced ultrasound imaging. The targeted lipid nanobubbles revealed uniform, round morphology, and good stability with a nanoscale size. Besides, BRAFV600Emonoclonal antibody was observed to be combined on the surface of lipid nanobubbles. Furthermore, the targeted nanobubbles had a good targeting diagnosis ability in PTC cells with BRAFV600Eoverexpression. Moreover, the targeted nanobubbles had better ultrasound enhancement and peak intensity of the time‐intensity curve (P< .001) in PTC tumors with BRAFV600Eoverexpression as compared to the untargeted lipid nanobubbles. The targeted lipid nanobubbles carrying BRAFV600Eantibody could be regarded as a potential targeted ultrasound contrast agent for the diagnosis of high‐risk PTC. Access the CME test hereand search by article title.

Periocular infantile hemangioma (pIH) is associated with a risk of vision loss and requires urgent medical intervention. We evaluated the outcomes of the comprehensive management of 44 pIH patients (aged 2–6 months) with superficial (n = 11), deep (n = 15), and mixed (n = 18) subtypes, treated with a standard propranolol dose (2 mg kg−1d−1) without any obvious side effects. Obvious and slight improvements were observed in 70.5% and 29.5% of patients, respectively. Obvious improvement was found in 96.3% of patients 3 months or younger but only 29.4% of patients older than 3 months (P= 0.036) after 4 weeks of treatment. Thirteen patients demonstrated slight improvement and were treated with an increased propranolol dose (3 mg kg−1d−1) in combination with corticosteroid injections or plastic surgery, which led to good outcomes. The patients were followed up for 12 to 18 months, with no cases of amblyopia or ametropia. Oral propranolol was effective in the treatment of pIH. Earlier propranolol use was associated with better outcomes. An increased propranolol dose combined with corticosteroid injections or plastic surgery is appropriate for patients with propranolol resistance.

It is generally accepted that N-heterocyclic carbene (NHC)-catalyzed imine transformations are initiated by a nucleophilic attack (NA) by NHC. However, due to significant nucleophilicity of the iminyl nitrogen atom in imines, the electrophilic attack (EA) by electrophiles onto imine would also be a possible mechanism of these kinds of reactions. Therefore, we use the quantum mechanical approach to disclose that both the NA and EA modes could be switchable for a wide range of NHC-catalyzed transformations of imines.

To investigate the relationship between ocular fundus abnormalities and cytokines in patients with severe viral pneumonia, aiming to provide targeted diagnostic recommendations.

In this paper, we develop a computable general equilibrium (CGE) model to shed quantitative light on the implications of a scenario of deeper economic integration between Canada and the United States, where the barriers for foreign direct investment are preferentially eliminated. Our model distinguishes between the activities of domestic and foreign-owned firms at the microeconomic level, both in terms of demand and production characteristics. Overall our findings suggest that further investment liberalization between the two countries will accelerate the shaping of Canada's industrial structure, as manifested by recent trends. Keywords FDI * Free trade * Canada-USA * CGE JEL F10 * O50, Introduction On January 1, 1989, Canada and the United States of America (USA) signed a free trade agreement (FTA), the Canadian-United States Free Trade Agreement (CUSFTA). Virtually all tariffs on [...]

A long-term (6-year), one-off application of biochar was conducted in a highly saline-alkali paddy field.Biochar consistently decreased soil BD, increased Tp, Ks, and improved soil aggregates.Biochar showed a sustained ability to alleviate saline-alkali stress.The continuous improvement of soil functions acted on the increase of rice yield.

Collaborative learning methods which emphasize peer interaction have been widely applied to increase the intensity and effectiveness of EFL reading programs. However, simply grouping students heterogeneously and assigning them group […]

A multisubstituted tetrahydrofuran building block bearing three vicinal chiral carbon centers widely exists in a broad spectrum of bioactive natural products, and the development of efficient and convenient methods to establish this skeleton remains a challenging task. Herein, we have developed an efficient method for the construction of significant tetrahydrofuran scaffolds bearing three vicinal and α-quaternary chiral carbon stereocenters through Pd-catalyzed asymmetric [3 + 2] annulation of vinylethylene carbonates with alkenes installed on cyclic N-sulfonyl imines. A series of multisubstituted tetrahydrofuran derivatives are obtained in high efficiencies with excellent enantioselectivities and diastereoselectivities. Density functional theory (DFT) studies are accomplished to rationalize the stereocontrol of the annulation process and disclose that methanol could be applied to stabilize the reactive zwitterionic π-allylpalladium via the H-bond interaction.

Arteriogenesis rather than unspecialized capillary expansion is critical for restoring effective circulation to compromised tissues in patients. Deciphering the origin and specification of arterial endothelial cells during embryonic development will shed light on the understanding of adult arteriogenesis. However, during early embryonic angiogenesis, the process of endothelial diversification and molecular events underlying arteriovenous fate settling remain largely unresolved in mammals. Here, we constructed the single-cell transcriptomic landscape of vascular endothelial cells (VECs) during the time window for the occurrence of key vasculogenic and angiogenic events in both mouse and human embryos. We uncovered two distinct arterial VEC types, the major artery VECs and arterial plexus VECs, and unexpectedly divergent arteriovenous characteristics among VECs that are located in morphologically undistinguishable vascular plexus intra-embryonically. Using computational prediction and further lineage tracing of venous-featured VECs with a newly developed Nr2f2CrexERmouse model and a dual recombinase-mediated intersectional genetic approach, we revealed early and widespread arterialization from the capillaries with considerable venous characteristics. Altogether, our findings provide unprecedented and comprehensive details of endothelial heterogeneity and lineage relationships at early angiogenesis stages, and establish a new model regarding the arteriogenesis behaviors of early intra-embryonic vasculatures.

Synthetic procyanidins-metallic compounds study the infrared spectral properties and ultraviolet spectral properties of mates, to study the free radical scavenging ability of procyanidins and the antioxidant ability of procyanidins complexes under different pH buffer solutions, provide a certain theoretical basis for future research and application of procyanidins. In addition to antibacterial, anti-radiation, anti-allergy and other functions, proanthocyanidins can also inhibit tumor. However, few people have studied the coordination reaction of procyanidins with Bovine serum albumin and metal ions, so it has great research value. In this paper, the optical activity of the complex will be preliminarily studied, which will lay a theoretical foundation for the development of drug fluorescence probe in the future.

Diradical generation followed by radical–radical cross-coupling is a powerful synthetic tool, but its detailed mechanism has yet to be established. Herein, we proposed and confirmed a new model named relayed proton-coupled electron transfer (relayed-PCET) for diradical generation, which could open a door for new radical–radical cross-coupling reactions. Quantum mechanics calculations were performed on a selected carbene-mediated diradical cross-coupling reaction model and a designed model, and the exact electronic structural changes during the radical processes have been observed for the first time.

The catalytic asymmetric dearomatization reaction of non-functionalized arenes poses a long-standing synthetic challenge to organic chemists because of the relative ease of rearomatization via the departure of a proton. In this work, the direct dearomatization of non-functionalized 1-naphthols was achieved through a phosphoric acid-catalyzed asymmetric (3+2) annulation reaction with azoalkenes. The reported convergent method allows the use of readily available simple 1-naphthols without pre-functionalization under mild conditions, furnishing a variety of tricyclic hexahydrobenz[e]indole derivatives in good yields and excellent enantioselectivities (75%–96% yields and 92%–99% ee). Density functional theory (DFT) calculations were performed to gain insights into the origins of the observed chemo-, regio-, and enantioselectivities. It is noteworthy that using azoalkenes as 1,3-dipole surrogates, in combination with powerful chiral phosphoric acid (CPA) catalysis, was key to the success of current reaction.

Density functional theory calculations were employed to study the mechanism of the Cu-catalyzed alkynylation of the N-sulfonyl α-ketiminoester with phenylacetylene. Based on the characteristics of the terminal alkyne, two possible pathways were proposed and investigated. The favorable reaction pathway includes copper acetylide generation, outer-sphere nucleophilic addition, and protonation. Nucleophilic addition is considered to be the rate- and enantioselectivity-determining step. The oxidative state of Cu(I) remains unchanged in the whole process. The electrophilic attack of the C–C triple bond by the N-sulfonyl ketimine to form the vinyl cation intermediate is shown to be unfavorable. The independent gradient model analysis revealed that the origin of the enantioselectivity comes from the weak hydrogen bond between the ligand and the sulfonamide substrate. Moreover, the side-arm effect controls the enantioselectivity by restricting the distortion of the ligand. This work would be of benefit for the design of new ligands for copper catalysis.

Metabotropic glutamate receptor 2 (mGluR2) is a therapeutic target for several neuropsychiatric disorders. An mGluR2 function in etiology could be unveiled by positron emission tomography (PET). In this regard, 5-(2-fluoro-4-[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3-b]pyridine-7-carboxamide ([11C]13, [11C]mG2N001), a potent negative allosteric modulator (NAM), was developed to support this endeavor. [11C]13was synthesized via the O-[11C]methylation of phenol 24with a high molar activity of 212 ± 76 GBq/μmol (n= 5) and excellent radiochemical purity (>99%). PET imaging of [11C]13in rats demonstrated its superior brain heterogeneity and reduced accumulation with pretreatment of mGluR2 NAMs, VU6001966 (9) and MNI-137 (26), the extent of which revealed a time-dependent drug effect of the blocking agents. In a nonhuman primate, [11C]13selectively accumulated in mGluR2-rich regions and resulted in high-contrast brain images. Therefore, [11C]13is a potential candidate for translational PET imaging of the mGluR2 function.

Objective: To observe the clinical efficacy of umbilical therapy with herbal cakes made of Ge Gen Qin Lian Tang prescription of different dosages in treating damp-heat diarrhea in young children. Methods: Seventy-two kids with diarrhea of damp-heat pattern were recruited and divided into a high-dosage group and a low-dosage group using the random number table method, with 36 cases in each group. They all received conventional antidiarrheal treatment and umbilical application with herbal cakes. However, the herbal cakes for the high-dosage group were made of the mixture of Ge Gen Qin Lian Tang powder and water, and those for the low-dosage group consisted of 10% Ge Gen Qin Lian Tang powder and 90% auxiliary materials (corn starch) plus water. The treatment duration was 3 d. The clinical efficacy, antidiarrheal rate, effective rate for symptoms and signs of traditional Chinese medicine (TCM), TCM symptoms score, and safety indicators were compared between the two groups. Results: After the treatment, the TCM symptoms scores dropped significantly in both groups (P&lt;0.01) and were lower in the high-dosage group than in the low-dosage group (P&lt;0.05). The clinical efficacy was more significant in the high-dosage group than in the low-dosage group after the treatment, and the between-group difference was statistically significant (P&lt;0.05); the antidiarrheal rate was markedly higher in the high-dosage group than in the low-dosage group (P&lt;0.05). Regarding the TCM symptoms and signs, the high-dosage group showed better results in improving the greasy and yellowish tongue coating, bowel movement frequency, watery excrement, short and dark urine, red tongue body, red anus, vomiting, bowel sounds, and abdominal bloating compared with the low-dosage group, and the between-group differences were statistically significant (P&lt;0.01). Conclusion: Umbilical therapy with herbal cakes made of Ge Gen Qin Lian Tang is safe, reliable, and effective in treating damp-heat diarrhea in young children; the high-dosage herbal cakes produce more significant efficacy than the low-dosage ones and are worth further investigation.

Double electron–electron resonance (DEER) is a powerful technique for studying protein conformations. To preserve the room-temperature ensemble, proteins are usually shock-frozen in liquid nitrogen prior to DEER measurements. The use of cryoprotectant additives is, therefore, necessary to ensure the formation of a vitrified state. Here, we present a simple modification of the freezing process using a flexible fused silica microcapillary, which increases the freezing rates and thus enables DEER measurement without the use of cryoprotectants. The Bid protein, which is highly sensitive to cryoprotectant additives, is used as a model. We show that DEER with the simple modification can successfully reveal the cold denaturation of Bid, which was not possible with the conventional DEER preparations. The DEER result reveals the nature of Bid folding. Our method advances DEER for capturing the chemically and thermally induced conformational changes of a protein in a cryoprotectant-free medium.

Magnetic nanoparticles (MNPs) are useful for magnetic targeted drug delivery while ligand-mediated active targeting is another common delivery strategy for cancer therapy. In this work, we intend to prepare magnetic graphene oxide (mGO) by chemical co-precipitation of MNPs on the GO surface, followed by conjugation of the gastrin releasing peptide (GRP) as a targeting ligand, for dual targeted drug/gene delivery in invasive brain glioma treatment. mGO was grafted with chitosan, complexed with shRNA plasmid DNA for stomatin-like protein 2 (SLP2) gene silencing, modified with urocanic acid for plasmid DNA endosomal escape, PEGylated for GRP conjugation, and loaded with the chemotherapeutic drug irinotecan (CPT-11) by π–π interaction for pH-responsive drug release (mGOCUG/CPT-11/shRNA). In addition to the in depth characterization of the physico–chemical and biological properties during each preparation step, we also study the loading/pH-responsive release behavior of CPT-11 and the shRNA plasmid loading/cell transfection efficiency. The targeting and antitumor efficacies of the nanocomposite were studied with U87 human glioblastoma cells in vitro. An in vivostudy revealed that intravenous administration followed by magnetic guidance results in the efficient targeted delivery of mGOCUG/CPT-11/shRNA to orthotopic brain tumors in nude mice, and it exhibits excellent antitumor efficacy with a reduced tumor growth rate and prolonged animal survival time. Our work thus highlights a multifunctional mGO-based drug/gene delivery platform for effective combination cancer therapy in glioblastoma treatment.

The high efficiency of widely applied Noyori-type hydrogenation catalysts arises from the N–H moiety coordinated to a metal centre, which stabilizes rate-determining transition states through hydrogen-bonding interactions. It was proposed that a higher efficiency could be achieved by substituting an N–M′ group (M′ = alkali metals) for the N–H moiety using a large excess of metal alkoxides (M′OR); however, such a metal-hydride amidate intermediate has not yet been isolated. Here we present the synthesis, isolation and reactivity of a metal-hydride amidate complex (HMn–NLi). Kinetic studies show that the rate of hydride transfer from HMn–NLi to a ketone is 24-fold higher than that of the corresponding amino metal-hydride complex (HMn–NH). Moreover, the hydrogenation of N-alkyl-substituted aldimines was realized using HMn–NLi as the active catalyst, whereas HMn–NH is much less effective. These results highlight the superiority of M/NM′ bifunctional catalysis over the classic M/NH bifunctional catalysis for hydrogenation reactions.

Nonimmune cells can have immunomodulatory roles that contribute to healthy development. However, the molecular and cellular mechanisms underlying the immunomodulatory functions of erythroid cells during human ontogenesis remain elusive. Here, integrated, single-cell transcriptomic studies of erythroid cells from the human yolk sac, fetal liver, preterm umbilical cord blood (UCB), term UCB and adult bone marrow (BM) identified classical and immune subsets of erythroid precursors with divergent differentiation trajectories. Immune-erythroid cells were present from the yolk sac to the adult BM throughout human ontogenesis but failed to be generated in vitro from human embryonic stem cells. Compared with classical-erythroid precursors, these immune-erythroid cells possessed dual erythroid and immune regulatory networks, showed immunomodulatory functions and interacted more frequently with various innate and adaptive immune cells. Our findings provide important insights into the nature of immune-erythroid cells and their roles during development and diseases.

Development of miniaturized three-dimensional (3D) fliers with integrated functional components has important implications to a diverse range of engineering areas. Among the various active and passive miniaturized 3D fliers reported previously, a class of 3D electronic fliers inspired by wind-dispersed seeds show promising potentials, owing to the lightweight and noiseless features, aside from the stable rotational fall associated with a low falling velocity. While on-demand shape-morphing capabilities are essential for those 3D electronic fliers, the realization of such miniaturized systems remains very challenging, due to the lack of fast-response 3D actuators that can be seamlessly integrated with 3D electronic fliers. Here we develop a type of morphable 3D mesofliers with shape memory polymer (SMP)-based electrothermal actuators, capable of large degree of actuation deformations, with a fast response (e.g., ∼1 s). Integration of functional components, including sensors, controllers, and chip batteries, enables development of intelligent 3D mesoflier systems that can achieve the on-demand unfolding, triggered by the processing of real-time sensed information (e.g., acceleration and humidity data). Such intelligent electronic mesofliers are capable of both the low-air-drag rising and the low-velocity falling, and thereby, can be used to measure the humidity fields in a wide 3D space by simple hand throwing, according to our demonstrations. The developed electronic mesofliers can also be integrated with other types of physical/chemical sensors for uses in different application scenarios.

Green-fluorescent nitrogen-doped carbon quantum dots (g-CQDs) were synthesized via a simple and convenient one-step hydrothermal method using Passiflora edulis sims shellas a carbon source and m-phenylenediamine as a nitrogen source and applied to the detection of uric acid. Unlike most reported blue fluorescent probes, the obtained g-CQDs showed bright-green fluorescence under ultraviolet light with a high quantum yield of 37.6%. Moreover, the g-CQDs exhibit outstanding photostability and high sensitivity, an excellent linearity ranging from 1 to 17 µM, and a great limit of detection of 0.94 µM, which renders them suitable for the determination of uric acid in human urine with remarkable selectivity.