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Abstract The bottleneck of large‐scale implementation of electrocatalytic water‐splitting technology lies in lacking inexpensive, efficient, and durable catalysts to accelerate the sluggish oxygen evolution reaction kinetics. Owing to more metallic features, transition metal telluride (TMT) with good electronic conductivity holds promising potential as an ideal type of electrocatalysts for oxygen evolution reaction (OER), whereas most TMTs reported up to now still show unsatisfactory OER performance that is far below corresponding sulfide and selenide counterparts. Here, the activation and stabilization of cobalt telluride (CoTe) nanoarrays toward OER through dual integration of sulfur (S) doping and surface oxidization is reported. The as‐synthesized CoO@S‐CoTe catalyst exhibits a low overpotential of only 246 mV at 10 mA cm−2 and a long‐term stability of more than 36 h, outperforming commercial RuO2 and other reported telluride‐based OER catalysts. The combined experimental and theoretical results reveal that the enhanced OER performance stems from increased active sites exposure, improved charge transfer ability, and optimized electronic state. This work will provide a valuable guidance to release the catalytic potential of telluride‐based OER catalysts via interface modulating engineering.

Background/Aims: Regulatory T cells (Tregs) play key roles in maintaining peripheral tolerance and preventing autoimmune disease. Treg modulation could be helpful in treating malignancies, autoimmune disease, and allergies, as well as to facilitate organ transplantation. Signals transduced by co-stimulatory molecules are essential for Treg differentiation, homeostasis, and function. One well-known active receptor, CD226, also known as DNAM-1 or PTA1, is an adhesion molecule that interacts primarily with CD155 and is involved in Treg differentiation and immune tolerance to transplanted tissue. Methods: Anti-CD226 monoclonal antibody (mAb) and truncated recombinant CD226 proteins were employed to manipulate the CD226 signal. Various T cell markers on freshly isolated splenocytes and T lymphocytes were characterized by flow cytometry Cell proliferation was measured by carboxyfluorescein succinimidyl ester dye, mRNA transcripts by q-RT PCR, and protein expression by western blotting. A BALB/c-to-C57BL/6 skin allograft model was used to determine the effects of CD226 blocking treatment. Results: We observed that both intact extracellular domains of CD226 were necessary for functional interaction of the receptor with its ligand CD155, even though one domain was shown to bind CD155 with lower affinity in a solid binding assay. Importantly, CD226 mAb promoted Treg expansion in a mixed lymphocyte culture and inhibited the cytotoxicity of effector cells. In allogeneic skin transplant mice, administering CD226 mAb reduced inflammation and prolonged allogeneic graft survival, with an increase in the frequency of Tregs. Conclusions: Our results reveal the mechanism underlying CD226-CD155 interactions and indicate that CD226 signals can be manipulated to promote Treg expansion. Moreover, we provide new evidence that suggests the therapeutic potential of anti-CD226 with allogeneic transplantation.

Introduction. PET imaging is a useful clinical tool for studying tumor progression and treatment effects. Conventional 18F-FDG-PET imaging is of limited usefulness for imaging Glioblastoma Multiforme (GBM) due to high levels of glucose uptake by normal brain and the resultant signal-to-noise intensity. 18F-Fluorothymidine (FLT) in contrast has shown promise for imaging GBM, as thymidine is taken up preferentially by proliferating cells. These studies were undertaken to investigate the effectiveness of 18F-FLT-PET in a GBM mouse model, especially after radiation therapy (RT), and its correlation with useful biomarkers, including proliferation and DNA damage. Methods. Nude/athymic mice with human GBM orthografts were assessed by microPET imaging with 18F-FDG and 18F-FLT. Patterns of tumor PET imaging were then compared to immunohistochemistry and immunofluorescence for markers of proliferation (Ki-67), DNA damage and repair (γH2AX), hypoxia (HIF-1α), and angiogenesis (VEGF). Results. We confirmed that 18F-FLT-PET uptake is limited in healthy mice but enhanced in the intracranial tumors. Our data further demonstrate that 18F-FLT-PET imaging usefully reflects the inhibition of tumor by RT and correlates with changes in biomarker expression. Conclusions. 18F-FLT-PET imaging is a promising tumor imaging modality for GBM, including assessing RT effects and biologically relevant biomarkers.

Existence of a weak solution is established for the initial-boundary value problem for the system ∂∂tu−div (θ(u)∇u)+σ(u)α(u)∇u∇v=σ(u)|∇v|2, div (σ(u)∇v)=0. The question of uniqueness is also considered in some special cases.

In the crystal structure of the title compound, C22H17BrO6, the quinone ring makes a dihedral angle of 81.84 (3)° with the benzene ring. The chiral C atoms, viz. the ring C atoms bearing the hydroxy and bromophenyl substituents, exhibit R and S configurations, respectively. The terminal ethyl group of the –CO2CH2CH3 group is disordered over two sets of sites with site-occupancy factors of 0.64 (1) and 0.36 (1). Intermolecular O—H...O interactions further stabilize the crystal packing.

The absolute configuration in the title of the paper by Wang, Zhang, Xu & Zhang [Acta Cryst. (2010), E66, o217] is corrected.

There are issues with flexible DC transmission system such as a lack of control freedom over power flow. In order to tackle these issues, a DC power flow controller (DCPFC) is incorporated into a multi-terminal, flexible DC power grid. In recent years, a multi-port DC power flow controller based on a modular multi-level converter has become a focal point of research due to its simple structure and robust scalability. This work proposes a model predictive control (MPC) strategy for multi-port interline DC power flow controllers in order to improve their steady-state dynamic performance. Initially, the mathematical model of a multi-terminal DC power grid with a multi-port interline DC power flow controller is developed, and the relationship between each regulated variable and control variable is determined; The power flow controller is then discretized, and the cost function and weight factor are built with numerous control objectives. Sub module sorting method and nearest level approximation modulation regulate the power flow controller; Lastly, theMATLAB/Simulink simulation platformis used to verify the correctness of the establishedmathematicalmodel and the control performance of the suggestedMPC strategy. Finally, it is demonstrated that the control strategy possesses the benefits of robust dynamic performance, multiobjective control, and a simple structure. [ABSTRACT FROM AUTHOR]

Background: Hemoglobin (HGB) was the most important factors which could cause dysmenorrhea in women. Metals exposure and hemoglobin level in dysmenorrhea female was unclear. We aimed to explore the associations of multi-metal exposure and HGB level in female college students with dysmenorrhea. Methods: 253 female students who had dysmenorrhea was included in our study. The Last Absolute Shrinkage and Selection Operator (LASSO) regression, generalized linear model (GLM), and Bayesian Kernel Machine Regression (BKMR) models were used to explore the associations of multi-metal exposure and HGB levels in female college students with dysmenorrhea. Results: GLM results showed that plasma Fe, Ni and Rb was positively associated with HGB and plasma Co was negatively associated with HGB. In menarche age ≤13 years old group, plasma Co and Rb only was negatively and positively associated with HGB level, respectively, and plasma Ni had positive association with HGB level in menarche age >13 years old group. BKMR results showed the reverse U-shaped relationship between the five metals mixture (Co, Fe, Ni, Cu and Rb) and HGB levels in overall and menarche age ≤13 years old group. However, there were positive association between the five metals mixture and HGB levels in menarche age >13 years old group. Conclusion: Our present study revealed that metals (Fe, Ni, Co, Rb, Cu) mixture exposure could effect HGB levels in female college students with dysmenorrhea. And the relationships were different during different menarche age in female college students.

The manufacturing of crystal films lies at the heart of modern nanotechnology. How to accurately predict the motion of a crystal surface is of fundamental importance. Many continuum models have been developed for this purpose, including a number of PDE models, which are often obtained as the continuum limit of a family of kinetic Monte Carlo models of crystal surface relaxation that includes both the solid-on-solid and discrete Gaussian models. In this paper we offer an analytical perspective on some of these models. To be specific, we study the existence of a weak solution to the boundary value problem for the equation -Δe-div(|∇u|p-2∇u) + au = f, where p > 1,a > 0 are given numbers and f is a given function. This problem is derived from a crystal surface model proposed by J. L. Marzuola and J. Weare [Phys. Rev. E, 88 (2013), 032403]. The mathematical challenge is due to the fact that the principal term in our equation is an exponential function of a p-Laplacian. Existence of a suitably defined weak solution is established under the assumptions that p ∈ (1, 2], N ≤ 4, and f ∈ W1,p. Our investigations reveal that the key to our existence assertion is how to control the set where -div(|∇u|p-2∇u) is ±∞. [ABSTRACT FROM AUTHOR]

An unexpected regioselective I2/TBHP-mediated 1,2-iodo-oxygenation of alkenes with N-hydroxylamines is described. The reaction proceeds through a radical coupling mechanism or a iodonium mechanism, which is controlled by the structures of both N-hydroxyl-amines and alkenes, to form vicinal iodo-substituted N-alkoxyamines regioselectively. Both the iodo and alkoxyamine group of the resulting products offer rich possibilities of synthetic manipulations. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to the World Health Organization statistics, more than 500 million individuals have been infected and more than 6 million deaths have resulted worldwide. Although COVID-19 mainly affects the respiratory system, considerable evidence shows that the digestive, cardiovascular, nervous, and reproductive systems can all be involved. Angiotensin-converting enzyme 2 (AEC2), the target of SARS-CoV-2 invasion of the host is mainly distributed in the respiratory and gastrointestinal tract. Studies found that microbiota contributes to the onset and progression of many diseases, including COVID-19. Here, we firstly conclude the characterization of respiratory, gut, and oral microbial dysbiosis, including bacteria, fungi, and viruses. Then we explore the potential mechanisms of microbial involvement in COVID-19. Microbial dysbiosis could influence COVID-19 by complex interactions with SARS-CoV-2 and host immunity. Moreover, microbiota may have an impact on COVID-19 through their metabolites or modulation of ACE2 expression. Subsequently, we generalize the potential of microbiota as diagnostic markers for COVID-19 patients and its possible association with post-acute COVID-19 syndrome (PACS) and relapse after recovery. Finally, we proposed directed microbiota-targeted treatments from the perspective of gut microecology such as probiotics and prebiotics, fecal transplantation and antibiotics, and other interventions such as traditional Chinese medicine, COVID-19 vaccines, and ACE2-based treatments.

A Sc(OTf)3-catalyzed aza-Friedel-Crafts reaction of electronrich arenes with isatin-derived ketimines is disclosed, providing biologically interesting 3-amino-3-aryl-2-oxindoles in moderate to good yields with broad substrate scope. This reaction can be easily scaled up, and the Boc protecting group could be readily removed under mild reaction conditions to afford the free amine. [ABSTRACT FROM AUTHOR]

In this paper we are concerned with the existence of a weak solution to the initial boundary value problem for the equation ∂u/ ∂t = Δ(Δu) -3. This problem arises in the mathematical modeling of the evolution of a crystal surface. Existence of a weak solution u with Δu ≥ 0 is obtained via a suitable substitution. Our investigations reveal the close connection between this problem and the equation ∂tρ+ρ2Δ2ρ3 = 0, another crystal surface model first proposed by H. Al Hajj Shehadeh, R. V. Kohn, and J. Weare [Phys. D, 240 (2011), pp. 1771-1784]. [ABSTRACT FROM AUTHOR]

In this paper we study the existence assertion of the initial boundary value problem for the equation ... This problem arises in the mathematical description of the evolution of crystal surfaces. Our investigations reveal that the exponent in the equation can have a singular part in the sense of the Lebesgue decomposition theorem, and the exponential nonlinearity somehow "cancels" it out. The net result is that we obtain a solution u that satisfies the equation and the initial boundary conditions in the almost everywhere (a.e.) sense. [ABSTRACT FROM AUTHOR]

A metal-free TBHP-mediated radical alkylation of enol acetates with alcohols is described. This method provides a new route to a variety of β-hydroxy-ketones in moderate to good yields. [ABSTRACT FROM AUTHOR]

A new MnO2-catalyzed oxidative alkylation of enamides with a C(sp3)-H bond adjacent to an oxygen atom is described. This method achieves a C(sp3)-H/C(sp2)-H cross-dehydrogenative coupling and hydrolysis, thus providing efficient and general access to a variety of β-oxo ketones. [ABSTRACT FROM AUTHOR]

A convenient synthetic approach to α-iodonitro alkenes based on the iodonitration of alkynes with tBuONO and I2 is described. No acid or oxidant is required in this reaction. [ABSTRACT FROM AUTHOR]

An intramolecular allylic arylation protocol for the synthesis of indene derivatives from readily available Baylis-Hillman acetates via palladium-catalyzed C-H bond activation has been developed. [ABSTRACT FROM AUTHOR]

A novel arylalkoxycarbonylation of N-aryl acrylamides with carbazates leading to alkoxycarbonylated oxindoles has been developed. The reported reactions employ economical and environmentally benign FeClM2 · 4H2O as a catalyst and easily accessible and safe carbazates as alkoxycarbonyl radical precursors. INSET: 83;. [ABSTRACT FROM AUTHOR]

In this paper we present a simplified version of a coercivity inequality due to Gianazza, Savaré, and Toscani [The Wasserstein gradient flow of the Fisher information and the quantum drift-diffusion equation, Arch. Ration. Mech. Anal. 194 (2009) 133-220]. Then we use the inequality to construct a weak solution to the initial-boundary value problem for the viscous quantum Euler model. [ABSTRACT FROM AUTHOR]

A catalytic system consisting of KI, 18-crown-6, and TBHP for arylsulfonylation of activated alkenes with sulfonylhydrazides as sulfonyl precursor is described. This protocol provides a practical and environmentally benign method for the construction of sulfonated oxindoles in water. [ABSTRACT FROM AUTHOR]

A concise, one-step synthesis of substituted fluorenes through TiCl4-promoted cascade allenylation, electrocyclization and intramolecular Friedel-Crafts reaction of 1,3-diene-substituted propargylic alcohols has been developed. An interesting substituent-dependent regioselectivity was observed. [ABSTRACT FROM AUTHOR]

A regiospecific synthesis of 3,4-dihydrocoumarin derivatives has been achieved involving tandem rearrangement-cyclization of (E)-2-(aryloxymethyl)alk-2-enoates catalyzed by a Pd/Cu bimetallic system. Unexpected substrate-controlled [1,3]- or [3,3]-sigmatropic rearrangement was observed in the transformations. [ABSTRACT FROM AUTHOR]

We investigate the boundedness of weak solutions to the initial boundary-value problemfor the system ... in the case where K (u), σ (u) may both tend to 0 as u → ∝ In particular, if solutions do blow up, our results impose a condition on the blow-up rates. [ABSTRACT FROM AUTHOR]

A partial regularity theorem is established for a particular class of weak solutions to the system ∂u/∂t - div(K(u) ∇ u) = σ(u)¦∇&psi&bravbar;^2, div(σ(u)∇ψ= 0 on a bounded domain in R^N. Under our assumptions, σ(u) may exhibit exponential decay, and thus the system may be degenerate. Our proof is based upon a blow-up argument. [ABSTRACT FROM AUTHOR]