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A new method was developed to synthesize N2-allyl-substituted 1,2,3-triazoles via NIS mediated allylation of allenamides with mono- and unsubstituted NH-1,2,3-triazoles and benzotriazole. All the N2-allyl-substituted 1,2,3-triazoles have a relative stability. The ionic pair composed of a σ-complex and the conjugate base of the imide and the hydrogen bond between the conjugate base and NH-1,2,3-triazole were found to be generated, which selectively gave the desired N2-allylation products. [ABSTRACT FROM AUTHOR]

Multifunctional materials have rapidly attracted increasing attention owing to their novel, unpredictable, and unique properties, and potential applications in sensors, switches and smart materials. However, a lack of deeper understanding of performance optimization and structure–property relationships hampers the investigation of the coupling mechanism and further development of multifunctional materials. In this study, using the intrinsic merits of cocrystal materials and the strategy of molecular design, two isostructural 2D supramolecular cocrystal compounds [(H3betc)(H-Hopip)0.5·(H2O)] [OCC 1, H4betc = 1,2,4,5-benzenetetracarboxylic acid, Hopip = homopiperazine] and [(H3betc)2(H2-Mepip)·(H2O)] [OCC 2, Mepip = 2-methyl-piperazine] were successfully synthesized and further structurally characterized. OCC 1 and OCC 2 show different dielectric responses and proton conductivities due to the alteration of the carbon-skeleton of piperazine derivatives. Interestingly, a higher dielectric response (2480 at 100 Hz) and proton conductivity (3.65 × 10−4 S cm−1 at 298 K and ∼97% RH) is observed in OCC 2, which was better than those of some reported cocrystals, metal–organic framework materials and organic covalent compounds. The mechanism of dielectric response was also clearly elucidated by means of temperature-dependent Raman spectroscopy measurements. More importantly, there is good correlation between macroscopic properties and microscopic structures in OCC 1 and OCC 2. Furthermore, OCC 1 and OCC 2 show high dielectric constants and moderate proton conductivities under ambient conditions, which satisfies the criteria as the dispersed phase of electrorheological fluids. The study will provide valuable insight into investigating structure–property relationships for crystal materials at the atomic level, and also lay the foundation for the study of electrorheological fluids of organic cocrystal compounds. [ABSTRACT FROM AUTHOR]

Agent-based approach is a popular tool for modelling and developing large-scale distributed systems such as urban traffic control system with dynamic traffic flows. This study proposes a multi-agent-based approach to optimize urban traffic network signal control, which utilizes a mathematical programming method to optimize the signal timing plans at intersections. To improve the overall network efficiency, we develop an online agent-based signal coordination scheme, underpinned by the communication among different intersection control agents. In addition, the initial coordination scheme that pre-adjusts the offsets between the intersections is developed based on the historical demand information. Comparison and sensitivity analysis are conducted to evaluate the performance of the proposed method on a customized traffic simulation platform using MATLAB and VISSIM. Simulation results indicate that the proposed method can effectively avoid network oversaturation and thus reduces average travel delay and improves average vehicle speed, as compared to rule-based multi-agent signal control methods. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress is one of the main molecular events underlying pancreatic beta cell (PBC) failure, apoptosis, and a decrease in insulin secretion. Recent studies have highlighted the fundamental role of A2a adenosine receptor (A2aR) in potentiation of insulin secretion and proliferation of PBCs. However, possible protective effects of A2aR signaling against ER stress have not been elucidated yet. Thus, in the present study, we aimed to investigate the effects of A2aR activation in MIN6 beta cells undergoing tunicamycin (TM)‐mediated ER stress. A2aR expression and activity were evaluated using real‐time polymerase chain reaction and measurement of the cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), phospho‐protein kinase B or Akt (p‐Akt)/Akt, and phospho‐Cyclic adenosine monophosphate response element‐binding protein/CREB levels in response to a specific agonist (CGS 21680). Survival and proliferation in TM and CGS 21680 cotreated cells were evaluated using 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), annexin V–fluorescein isothiocyanate (FITC)/propidium iodide staining, colony formation, and 5‐bromo‐2′‐deoxyuridine (Brdu) assays. In addition, the effects of A2aR stimulation on insulin secretion were evaluated using the enzyme‐linked immunosorbent assay. B‐cell lymphoma 2 (Bcl‐2), phospho‐eukaryotic Initiation Factor 2α (p‐eIF2α)/eIF2α, growth arrest and DNA‐damage‐inducible 34 (GADD34), X‐box binding protein 1 (XBP‐1), spliced X‐box binding protein 1 (XBP‐1s), immunoglobulin heavy‐chain‐binding protein (BIP), and CCAAT‐enhancer‐binding protein homologous protein (CHOP) levels were evaluated using western blotting. Our results showed a decrease in A2aR expression and p‐Akt/Akt and p‐CREB/CREB levels in TM‐pretreated cells. We also mentioned that CGS 21680 effectively increased cell survival, proliferation, and insulin secretion in TM‐treated cells. The antiapoptotic effects were possibly mediated through Bcl‐2 upregulation. Our western blotting results indicated that A2aR effectively downregulated p‐eIF2α/eIF2α, XBP‐1, XBP‐1s, BIP, and CHOP levels, whereas GADD34 was upregulated. Altogether, the present study revealed that A2aR signaling through PKA/Akt/CREB mediators alleviated TM cytotoxicity effects in MIN6 beta cells. Thus, the stimulation of this receptor was seen as a new approach to control ER stress in the PBC cells. A2a adenosine receptor activation improved endoplasmic reticulum (ER) stress in pancreatic beta cells (PBCs) and its signaling may provide new approach to control ER stress in the PBC cells. [ABSTRACT FROM AUTHOR]

Integrated Project Delivery (IPD) has become increasingly popular in the architecture, engineering, and construction industries. However, the current practice status by the construction industry fails to deliver the desired results. In that backdrop, how to promote cooperation within and improve the overall performance of integrated project team has received wide attention. Herein, knowledge-sharing plays a critical role in cooperation and overall performance. However, to the best of our knowledge, the research on knowledge-sharing strategy interaction and evolutionary mechanism is rare. To make up for the deficiency of the studies existing, a novel model is proposed by taking advantage of evolutionary game theory, to capture the interaction behavior of knowledge-sharing and explore its evolutionary mechanism. Six parameters of knowledge stock, knowledge-sharing degree, heterogeneous knowledge proportion, synergy effect, knowledge absorption coefficient, and knowledge-sharing cost efficient that are critical to knowledge-sharing are extracted and defined. The payoff matrix is constructed by analyzing the benefits and costs of knowledge-sharing. Then, a replicator dynamic system is established based on payoff matrix, to determine the evolutionary tendency of knowledge-sharing behavior. Finally, numerical simulations are conducted to explore the influences of all parameters on the knowledge-sharing strategy. The findings in this research reveal that strategy interaction behavior is significantly influenced by proportion of strategy of choosing to share knowledge in both game players. The authors also find that strategy interaction behavior has a strong negative correlation with knowledge-sharing cost efficient, but has a positive correlation with knowledge stock, heterogeneous knowledge proportion, degree of knowledge-sharing, knowledge absorption coefficient, and synergetic effect coefficient. This research can provide the evolutionary mechanism and broaden our understanding of relationship between project performance and knowledge-sharing and can offer valuable guidance on improving cooperation and performance of project teams. [ABSTRACT FROM AUTHOR]

Molecular ferroelectrics as a class of promising information storage materials have triggered widespread attention owing to their light weight, easy processing and mechanical flexibility. However, reports of molecular ferroelectrics with high-temperature ferroelectric behaviour and higher spontaneous polarization are mainly focused on organic–inorganic perovskites, which are scarce in coordination compound avenues. Here, a pair of homochiral trinuclear Zn(ii) clusters formulated as R-[Zn3(R–L)2(CH3COO)4] (R-1) and S-[Zn3(S–L)2(CH3COO)4] (S-1) were successfully constructed with zinc(ii) and the enantiomeric chiral Schiff-base ligands (R/S)-HL (HL = 2-methoxy-6-[(1-phenyl-ethylimino)-methyl]-phenol) through a solvent diffusion method. The solid-state circular dichroism (CD) spectra perfectly illustrate the enantiomeric characteristics of R-1 and S-1. Interestingly, the trinuclear Zn(ii) cluster (R-1) exhibits unusual high-temperature ferroelectric behaviour at 503 K, when the external electric field is 12 KV cm−1, and the remnant polarity (Pr) and spontaneous polarization (Ps) of R-1 can reach up to 5.4 μC cm−2 and 8.45 μC cm−2, respectively, which are comparable with organic–inorganic perovskite ferroelectrics in the literature. To the best of our knowledge, it is the first example of a high-temperature ferroelectric possessing higher spontaneous polarization in Zn-based molecular ferroelectrics. [ABSTRACT FROM AUTHOR]

The “trash to treasure” process has been extensively demonstrated for various energy and environmental issues in the past few decades. Abundant biomass is well accepted as a carbon-rich, sustainable, and renewable precursor, offering us a plethora of possibilities for advanced materials for energy conversion and storage as well as environmental treatments; spatial modification of biomass facilitates the formation of a unique three-dimensional (3D) structure with micro- to macropores, yielding higher surface area and enhanced physicochemical properties. This novel concept provides sufficient reaction sites, excellent adsorption capability, more activated sites for catalyst doping, and fascinating electrochemical performance. Basically, the 3D cadre of biomass-derived carbon strengthens the economic competitiveness of these materials and broadens their applications in fields such as in supercapacitors, chemical batteries, bioenergy harvest, adsorbents for organic pollutants and greenhouse gases, and efficient (photo)catalysts. The scope of this review mainly focuses on the most popular synthesis methodology of three-dimensional carbon materials derived from biomass and their critical applications in the fields of energy and environment. [ABSTRACT FROM AUTHOR]

The conjoining and interfering influence of the Circum‐Pacific zone and the Tethys‐Himalayan zone make China a country of intense intracontinental seismicity. Here we provide three new quantitatively assessed products and use them to better constrain seismic hazards in China. First, we process ~2,700 Global Positioning System (GPS) data spanning 1996–2017 provided by the Crustal Movement Observation Network of China (CMONOC) network and the Nevada Geodetic Laboratory. To produce a robust tectonic velocity solution, we implement a data editing scheme to account for 8 Mw ≥ 7 earthquakes to reduce the influence of transient phenomena. The solution is then rotated into a consistent reference frame with 10 other published velocity sources surrounding mainland China. Second, we calculate a new geodetic strain rate model using an optimal mesh grid definition of 0.4° × 0.4° determined jointly by the Nyquist frequency method and checkerboard tests. We evaluate and validate the geodetic strain rate results from both a statistical (i.e., based on the Bayesian factor) and quantitative (i.e., based on the comparison with the 2‐D analytical strain rate result) approaches. Third, we use our new geodetic strain rate model to estimate seismicity rates. Key Points: Tectonic velocity solution for China derived from Global Positioning System data spanning 1996‐2017Using a novel checkerboard test, Bayesian statistics, and 2‐D analytic shear strain rates, we develop a tectonic strain rate model for ChinaTectonic forecast model of shallow seismicity for mainland China shows increased seismic risk in the North China Block [ABSTRACT FROM AUTHOR]

The dielectric properties of coordination polymers has been a topic of recent interest, but the role of different functional groups on the dielectric properties of these polymers has not yet been fully addressed. Herein, the effects of electron-donating (R=NH 2 ) and electron-withdrawing (R=NO 2 ) groups on the dielectric behavior of such materials were investigated for two thermally stable and guest-free Zn-based coordination polymers, [Zn(L 1 )(L 2 )] n (1) and [Zn(L 1 )(L 3 )] n (2) [L 1 =2-(2-pyridyl) benzimidazole (Pbim), L 2 =5-aminoisophthalate (Aip), and L 3 =5-nitroisophthalate (Nip)]. The results of dielectric studies of 1 revealed that it possesses a high dielectric constant (κ=65.5 at 1 kHz), while compound 2 displayed an even higher dielectric constant (κ=110.3 at 1 kHz). The electron donating and withdrawing effects of the NH 2 and NO 2 substituents induce changes in the polarity of the polymers, which is due to the inductive effect from the aryl ring for both NO 2 and NH 2 . Theoretical results from density functional theory (DFT) calculations, which also support the experimental findings, show that both compounds have a distinct electronic behavior with diverse wide bandgaps. The significance of the current work is to provide information about the structure-dielectric property relationships. So, this study promises to pave the way for further research on the effects of different functional groups on coordination polymers on their dielectric properties., (© 2022 Wiley-VCH GmbH.)

A palladium‐catalyzed γ‐C(sp3)–H acetoxylation of triflyl‐protected amines has been achieved. The use of pyridine or 2‐alkoxyquinoline‐type ligands is key to the success of this transformation. The reaction is highly diastereoselective and easily scalable, and constitutes a direct approach for the synthesis of γ‐hydroxy‐α‐amino acids and β,γ‐dihydroxy amines, which are not readily accessible by other routes. A palladium‐catalyzed γ‐C(sp3)–H acetoxylation of triflyl‐protected amines has been achieved. The use of pyridine or 2‐alkoxyquinoline‐type ligands is key to the success of this transformation. The reaction is highly diastereoselective and easily scalable, and constitutes a direct approach for the synthesis of γ‐hydroxy‐α‐amino acids and β,γ‐dihydroxy amines. [ABSTRACT FROM AUTHOR]

Developing new drugs for the treatment of cancer is of great significance. Coordination compounds based on tetrazole-carboxylates are the potential candidates for cancer treatment. In this article, [Ce2(atzpa)4(H2O)8](NO3)2·2H2O based on 5-aminotetrazole-1-propanoic acid (Hatzpa) and Ce(NO3)3·6H2O has been designed and prepared. Single-crystal X-ray diffraction reveals that the compound is binuclear in which atzpa acts as a bridging ligand. In order to improve the water dispersity of this compound, PEG-5000 (poly (ethyleneglycol-5000)) was coated on [Ce2(atzpa)4(H2O)8](NO3)2·2H2O to prepare the nanoparticles (NPS) in distilled water. In vitro study on HeLa cells shows that Hatzpa is nontoxic itself, while [Ce2(atzpa)4(H2O)8](NO3)2·2H2O NPs show high toxicity. Such NPs have a low half-inhibitory concentration (IC50) of 24lg mL-1 1 (2.0×10-5 M). In addition, such NPs are able to inhibit the migration of HeLa cells even at a low concentration effectively, showing their potential to inhibit the transfer of tumors in vivo. [ABSTRACT FROM AUTHOR]

Five transition metal–BTC–BIm based coordination polymers, namely [Zn2(HBTC)2(BIm)2(H2O)2]·(H2O)3, 1; [2-HABI]2[Zn2(BTC)2(2-ABI)(H2O)]·(H2O)5, 2; [Cu3(BTC)2(BIm)6][solvent], 3; [Co4(BTC)3(BIm)6][solvent], 4; and [(CH3CH2)2NH2][Zn(BTC)(BIm)]·(H2O), 5 have been synthesized and characterized using complementary techniques like single crystal X-ray analysis, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA) (BTC = 1,3,5-benzene tricarboxylic acid, BIm = benzimidazole and 2-ABI = 2-aminobenzimidazole). Crystal structure analysis of these compounds showed that 1 forms a 1D chain, 2 and 3 have 2D layers while 4 and 5 have three-dimensional architectures. 3 forms a hexagonal bronze sheet, 4 has a three-dimensional network with embedded paddlewheel SBUs and helical assembly, and 5 crystallizes in a polar space group (Pna21) with 3D helical networks with adamantane-type topology. The dielectric properties of 5 showed that the dielectric constant rapidly decreases with an increase in frequency suggesting dipole relaxation at low frequencies. [ABSTRACT FROM AUTHOR]

The anionic surfactant sodium oleate (NaOA) can self-assemble in aqueous solution in the presence of counter-ion inorganic salts to form wormlike micelles (WLMs), which exhibited viscoelastic behavior. In this paper, KCl was used to induce the formation of wormlike micelles with sodium oleate. In this process, we found that the addition of N, N-dimethylethanolamine (DMEA) can destroy the structure of WLMs leading significant decrease of viscosity. However, after introducing CO2 into the ternary solution (KCl-NaOA-DMEA), the WLMs can be regenerated due to the electrostatic interaction between the protonated DMEA and the anionic surfactants. The addition of sodium hydroxide (NaOH) causes the electrostatic interaction between OA- and DMEAH+ be destroyed, which results in the wormlike micelles becoming spherical micelles of lower viscosity. The transition of WLMs with high viscosity and low viscosity spherical micelles can be repeated several times by using CO2 and NaOH. [ABSTRACT FROM AUTHOR]

Abstract: The emergence of genomics and its use in combination with high-resolution bioimaging for the study of animal development mechanisms provide scientists with information on gene sets and regulation thereof during development. This enabled the identification of the core set of transcription factors involved in the development of invertebrates and vertebrates. This approach was particularly efficient due to the widespread use of transparent embryos of zebrafish and other bony fishes in these studies. These embryos can be used as model systems for the analysis of vertebrate development, even at the level of individual cells, as the various processes of development unfold in vivo. [ABSTRACT FROM AUTHOR]

In this paper, we calculated multi-scale residual geoid anomalies with the method of geoid separation processing, according to EGM2008 ultra-high order gravity field model, remove-restore technique and Stokes integral. The East Asian continental margin was selected as the study area. The residual geoid anomalies have been calculated by programming. On the basis of residual geoid anomalies at various orders, the interlayer geoid anomalies at different depths were calculated to depict the spatial distribution characteristics of the residual geoid. Finally, we conducted a detailed geophysical interpretation for the study area according to the geoid anomalies in combination with other geophysical datasets. Four conclusions can be outlined as follows: 1) it is impracticable that geoid anomalies are used in the interpretation of the shallow objects due to the influence of the terrain; 2) the anomalies of residual geoid can reflect the intensity of small-scale mantle convection in the asthenosphere; 3) the interlayer geoid anomalies can reflect the magmatic activities associated with the mantle convection and mantle plume in different scales; 4) the study of the geoid may provide an approach for the research of the subduction zone, mantle convection and mantle plume. [ABSTRACT FROM AUTHOR]

Forecasting for short-term ridership is the foundation of metro operation and management. A prediction model is necessary to seize the weekly periodicity and nonlinearity characteristics of short-term ridership in real-time. First, this research captures the inherent periodicity of ridership via seasonal autoregressive integrated moving average model (SARIMA) and proposes a support vector machine overall online model (SVMOOL) which insets the weekly periodic characteristics and trains the updated data day by day. Then, this research captures the nonlinear characteristics of the ridership via successive ridership value inputs and proposes a support vector machine partial online model (SVMPOL) which insets the nonlinear characteristics and trains the updated data of the predicted day by time interval (such as 5-min). Afterwards, to avoid the drawbacks and to take advantages of the strengths of the two individual online models, this research takes the average predicted values of two models as the final predicted values, which are called support vector machine combined online model (SVMCOL). Finally, this research uses the 5-min ridership at Zhujianglu and Sanshanjie Stations of Nanjing Metro to compare the SVMCOL model with three well-known prediction models including SARIMA, back-propagation neural network (BPNN), and SVM models. The resultant performance comparisons suggest that SARIMA is superior for the stable weekday ridership to other models. Yet the SVMCOL model is the best performer for the unstable weekend ridership and holiday ridership. It shows that for metro operation manager that gear toward timely response to real-world unstable and abnormal situations, the SVMCOL may be a better tool than the three well-known models. [ABSTRACT FROM AUTHOR]

Abstract: A one‐step scheme is presented to construct the controlled‐phase gate deterministically on remote transmon qutrits coupled to different resonators connected by a superconducting transmission line for an universal distributed quantum computing. Different from previous work on remote superconducting qubits, the present gate is implemented with coherent evolutions of the entire system in the all‐resonance regime assisted by the dark photons to robust against the transmission line loss, which allows the possibility of the complex designation of a long‐length transmission line to link lots of circuit QEDs. The length of the transmission line can reach the scale of several meters, which makes this scheme suitable for large‐scale distributed quantum computing. This gate is a fast quantum entangling operation with a high fidelity of about 99%. Compared with previous work in other quantum systems for a distributed quantum computing, under the all‐resonance regime, the present proposal does not require classical pulses and ancillary qubits, which relaxes the difficulty of its implementation largely. [ABSTRACT FROM AUTHOR]

The thermoresponsive poly(N-isopropylacrylamide) and matching thermal-liftoff method are widely employed for cell culture. There is already growing evidence that this special cell culture system not only provides an appropriate growth environment for anchorage-dependent cells at physiologic conditions, but also supports mild and efficient cell harvesting by cooling treatment. This review elaborates the internal and external factors affecting two-dimensional surface thermosensitivity and cell behavior, and then briefly discusses three-dimensional cell culture systems involved in thermosensitive microcarriers, scaffolds, hydrogels, and hollow fiber membranes, and finally presents their potential applications including large-scale cell expansion as well as tissue repair and reconstruction. [ABSTRACT FROM AUTHOR]

The East China Sea Shelf Basin (ECSSB) lies at the south‐eastern margin of the Eurasian Plate and was affected by the subduction of the Pacific Plate and the Philippine Plate. It experienced and recorded multistage tectonic inversions in the Cenozoic, especially in the Xihu Sag. In an attempt to investigate the evolution and mechanism of tectonic inversion, this paper presents numerical simulation results by the finite element method to the Xihu Sag. Combined with comprehensive structural analyses of seismic profiles, this paper determines the structural geometry of the sag for establishing a viscoelastic geologic model including six‐layer strata and nine major faults. Simulation results show that the boundary conditions of transtension and transpression control the inversion process that propagates from east to west, and the distribution of low compressive stress displays certain correlations with the distribution of oil deposits. Based on quantitative analysis of the vertical displacement field of the Xihu Sag, this paper identifies a tectonic inversion process, which indicates that the western part of the sag uplifts and the eastern part subsides during the first‐stage inversion; whereas the western part subsides and central‐eastern parts uplift during the second and third stages. The formation of the tectonic inversion is controlled by the adjustment of the stress field from dextral transtension to sinistral transpression caused by the change of subduction rates and direction of the Pacific Plate and the Philippine Sea Plate. [ABSTRACT FROM AUTHOR]

To address the increasing demands on pollution control and energy saving, the study of low-emission and high-efficiency burners has been emphasized worldwide. Swirl-induced environmental burners (EV-burners), have notable features aligned with these requirements. In this study, an EV burner is investigated by both an ECT system and an OH-PLIF system. The aim is to detect the structure of a flame and obtain more information about the combustion process in an EV burner. 3D ECT sensitivity maps are generated for the measurement and OH-PLIF images are acquired in the same combustion zone as for the ECT measurements. The experimental images of a flame by ECT are in good agreement with the OH radical distribution pictures captured by OH-PLIF, which provide a mutual verification of the visualization method. [ABSTRACT FROM AUTHOR]

Increasing evidence implicates astrocytes and the associated purinergic modulation in Alzheimer's disease (AD), characterized by cognitive deficits involving the extracellular amyloid-β peptides (Aβ) accumulation. Aβ can affect astrocytic gliotransmitters release, namely ATP, which is rapidly metabolized into adenosine by ecto-5'-nucleotidase, CD73, resulting in adenosine A 2A receptors (A 2A R) activation that bolsters neurodegeneration. AD's brains exhibit an upregulation of A 2A R and of connexin 43 (Cx43), which in astrocytes forms hemichannels that can mediate ATP release. However, a coupling between astrocytic A 2A R and Cx43 remains to be established. This was now investigated using astrocytic primary cultures exposed to Aβ 1-42 peptides. Aβ triggered ATP release through Cx43 hemichannels, a process blocked by A 2A R antagonists and mimicked by selective A 2A R activation. A 2A R directly regulated hemichannels activity and prevented Cx43 upregulation and phosphorylation observed in Aβ 1-42 -exposed astrocytes. Moreover, a proximity ligand assay revealed a physical association between astrocytic A 2A R and Cx43. Finally, the blockade of CD73-mediated extracellular formation of ATP-derived adenosine prevented the Aβ-induced increase of Cx43 hemichannel activity and of ATP release. Overall, the data identify a feed-forward loop involving astrocytic A 2A R and Cx43 hemichannels, whereby A 2A R increase Cx43 hemichannel activity leading to increased ATP release, which is converted into adenosine by CD73, sustaining the increased astrocytic A 2A R activity in AD-like conditions., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Lanthanide complexes have attracted a widespread attention due to their structural diversity, as well as multifunctional and tunable properties. The development of lanthanide based functional materials has often relied on the design of the secondary coordination sphere of the corresponding lanthanide complexes. For instance, usually simple lanthanide salts (solvento complexes) do not catalyze effectively organic reactions or provide low yield of the expected product, whereas the presence of a suitable organic ligand with a noncovalent bond donor or acceptor centre (secondary coordination sphere) modifies the symmetry around the metal centre in lanthanide complexes which then successfully can act as catalysts in both homogenous and heterogenous catalysis. In this minireview, we discuss several relevant examples, based on X-ray crystal structure analyses, in which the hydrogen, halogen, chalcogen, pnictogen, tetrel and rare-earth bonds, as well as cation-π, anion-π, lone pair-π, π-π and pancake interactions, are used as a synthon in the decoration of the secondary coordination sphere of lanthanide complexes., (© 2021 Wiley-VCH GmbH.)

The circumventricular organs (CVOs) are small structures lining the cavities of brain ventricular system. They are associated with the semitransparent regions of the blood-brain barrier (BBB). Hence it is thought that CVOs mediate biochemical signaling and cell exchange between the brain and systemic blood. Their classification is still controversial and development not fully understood largely due to an absence of tissue-specific molecular markers. In a search for molecular determinants of CVOs we studied the green fluorescent protein (GFP) expression pattern in several zebrafish enhancer trap transgenics including Gateways (ET33-E20) that has been instrumental in defining the development of choroid plexus. In Gateways the GFP is expressed in regions of the developing brain outside the choroid plexus, which remain to be characterized. The neuroanatomical and histological analysis suggested that some previously unassigned domains of GFP expression may correspond to at least six other CVOs-the organum vasculosum laminae terminalis (OVLT), subfornical organ (SFO), paraventricular organ (PVO), pineal (epiphysis), area postrema (AP) andmedian eminence (ME). Two other CVOs, parapineal and subcommissural organ (SCO) were detected in other enhancer-trap transgenics. Hence enhancer-trap transgenic lines could be instrumental for developmental studies of CVOs in zebrafish and understanding of the molecular mechanism of disease such a hydrocephalus in human. Their future analysis may shed light on general and specific molecular mechanisms that regulate development of CVOs. [ABSTRACT FROM AUTHOR]

Introduction: Functionalised carbon nanotubes (CNTs) have been shown to be promising biomaterials in neural systems, such as CNT -based nerve scaffolds to drive nerve regeneration. CNTs have been shown to modulate neuronal growth and improve electrical conductivity of neurons. Methods: Cultured astrocytes on the functionalized CNTs (PEG, caroboxyl group) were assessed for distribution of GABA, glutamate uptake assay using isotope and change of conductance of CNTs by ATP. Immunostaining of GABA using anti-GABA (red), anti-GFAP (green) antibody in primary cortical astrocytes on MW-CNT and PDL coverslips. Results: The functionalization of CNTs has improved their solubility and biocompatibility and alters their cellular interaction pathways. Recently, CNTs have been shown to modulate morphofunctional characteristics of glia as well as neurons. Among the various types of glia, astrocytes express diverse receptors for corresponding neurotransmitters and release gliotransmitters, including glutamate, adenosine triphosphate, and γ-amino butyric acid. Gliotransmitters are primarily released from astrocytes and play important roles in glia– neuron crosstalk. Conclusion: This review focuses on the effects of CNTs on glial cells and discusses how functionalized CNTs can modulate morphology and gliotransmitters of glial cells. Based on exciting new findings, they look to be a promising material for use in brain disease therapy or neuroprosthetics. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is considered one of the most malignant, genetically heterogeneous, and therapy-resistant solid tumor. Therapeutic options are limited in GBM and involve surgical resection followed by chemotherapy and/or radiotherapy. Adjuvant therapies, including antiangiogenic treatments (AATs) targeting the VEGF-VEGFR pathway, have witnessed enhanced infiltration of bone marrow-derived myeloid cells, causing therapy resistance and tumor relapse in clinics and in preclinical models of GBM. This review article is focused on gathering previous clinical and preclinical reports featuring major challenges and lessons in GBM. Potential combination therapies targeting the tumor microenvironment (TME) to overcome the myeloid cell-mediated resistance problem in GBM are discussed. Future directions are focused on the use of TME-directed therapies in combination with standard therapy in clinical trials, and the exploration of novel therapies and GBM models for preclinical studies. We believe this review will guide the future of GBM research and therapy. [ABSTRACT FROM AUTHOR]

Oblique plate convergence is common, but it is not clear how the obliquity is achieved by continental fold-and-thrust belts. We address this problem in the Qilian Shan, northeastern Tibetan Plateau, using fieldwork observations, geomorphic analysis, and elastic dislocation modeling of published geodetic data. A thrust dips SSW from the northern range front and underlies steeper thrusts in the interior. Cenozoic thrust-related shortening across the Qilian Shan is ~155-175 km, based on two transects. Elastic dislocation modeling indicates that horizontal strain in the interseismic period is consistent with oblique slip on a single low-angle detachment thrust below ~26 km depth, dipping SSW at ~17°. We suggest that this detachment is located above North China Block crust, originally underthrust during Paleozoic orogeny. Horizontal shear strain is localized directly above the updip limit of creep on the detachment and is coincident with the left-lateral Haiyuan Fault. This configuration implies that oblique slip on the detachment below seismogenic depths is partitioned in the shallow crust onto separate strike-slip and thrust faults. This is consistent with strain partitioning in oceanic subduction zones but has not previously been found by dislocation models of continental interiors. The marginal, strike-slip, Altyn Tagh Fault influences thrusting within the Qilian Shan for 100-200 km from the fault but does not control the regional structure, where Paleozoic basement faults have been reactivated. The Qilian Shan resembles the main Tibetan Plateau in nascent form: active thrusts are marginal to an interior that is developing plateau characteristics, involving low relief, and low seismicity. [ABSTRACT FROM AUTHOR]

The Buqingshan Tectonic Mélange Belt in the south margin of the East Kunlun Orogen, located in west section of Buqingshan-A'nyemaqen Suture Zone, is one of the key areas to understand continental tectonics and continental dynamics of China. This paper reports zircon U-Pb dating results and geochemistry of the Manite granodiorite (rock mass) in the Buqingshan Tectonic Mélange Belt. Zircons from the granodiorite show oscillatory zoning structures and relatively high Th/U ratios, indicating that they are magmatic zircons. Zircon LA-ICP-MS U-Pb dating for the Manite granodiorite yields ages of 487 ± 11 Ma (MSWD = 2.3) and 479 ± 2 Ma (MSWD = 0.56), implying that the Manite granodiorite were formed in the Late Cambrian to Early Ordovician. Geochemical analyses show that the rocks have high contents of SiO2 (66.06 wt.%-68.60 wt.%) and Al2O3 (14.84 wt.%-16.54 wt.%), and low alkaline (6.17 wt.%-7.43 wt.%), belonging to the middle-K calc-alkaline series. The A/CNK (Al2O3 /(CaO + Na2O + K2O)) ratios are 1.02-1.15, indicating that the granodiorite is weakly peraluminous. The contents of rare earth elements (REEs) are lower (89.64-130.41 ppm), with weakly negative to weakly positive Eu anomalies ( δEu = 0.83-1.12). The primitive mantle-normalized trace elements are characterized by evidently negative anomalies of Nb, Ta, P, Hf, Ti, etc., and positive anomalies of Th, La, Nd, Zr, Eu, etc. Moreover, the rocks show features of typical I-type granite. This leads us to conclude that the Manite granodiorites is derived from the partial melting of crust and formed in an island-arc environment. Combined with previous studies, we believe that the subduction of the Proto-Tethyan Ocean in the Buqingshan area was ongoing during 487 to 479 Ma and formed island-arc-type granites represented by the Late Cambrian to Early Ordovician Manite granodiorite. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Tomographic techniques have great abilities to interrogate the combustion processes, especially when it is combined with the physical models of the combustion itself. In this study, a data fusion algorithm is developed to investigate the flame distribution of a swirl-induced environmental (EV) burner, a new type of burner for low NOx combustion. An electric capacitance tomography (ECT) system is used to acquire 3D flame images and computational fluid dynamics (CFD) is applied to calculate an initial distribution of the temperature profile for the EV burner. Experiments were also carried out to visualize flames at a series of locations above the burner. While the ECT images essentially agree with the CFD temperature distribution, discrepancies exist at a certain height. When data fusion is applied, the discrepancy is visibly reduced and the ECT images are improved. The methods used in this study can lead to a new route where combustion visualization can be much improved and applied to clean energy conversion and new burner development. [ABSTRACT FROM AUTHOR]

Nematic order, a self-organized state with rotational symmetry broken, has been observed in both copper-oxide and iron-pnictide high temperature superconductors. However, its origin is still a mystery in the iron pnictides although it is considered as a key to understand the mechanism of superconductivity. Here, we report a systemic nuclear magnetic resonance (NMR) study on NaFeCoAs (0 ≤ x ≤ 0.042) that an orbital order, accompanied by an instant spin nematicity, occurs at at a temperature T far above structural transition temperature T in the tetragonal phase. We show that the observed NMR spectra splitting and its evolution is due to an incommensurate orbital order that sets in below T and becomes commensurate below T . We show that the electric field gradient asymmetry parameter is a good measure for the orbital order parameter which undergoes a Landau-like 2nd-order phase transition. We further show that the spin nematicity is well accounted for by the observed orbital order. [ABSTRACT FROM AUTHOR]

Four gridding methods for GPS velocities are compared in terms of their precision, applicability and robustness by analyzing simulated data with uncertainties from 0.0 to ±3.0 mm/a. When the input data are 1° × 1° grid sampled and the uncertainty of the additional error is greater than ±1.0 mm/a, the gridding results show that the least-squares collocation method is highly robust while the robustness of the Kriging method is low. In contrast, the spherical harmonics and the multi-surface function are moderately robust, and the regional singular values for the multi-surface function method and the edge effects for the spherical harmonics method become more significant with increasing uncertainty of the input data. When the input data (with additional errors of ±2.0 mm/a) are decimated by 50% from the 1° × 1° grid data and then erased in three 6° × 12° regions, the gridding results in these three regions indicate that the least-squares collocation and the spherical harmonics methods have good performances, while the multi-surface function and the Kriging methods may lead to singular values. The gridding techniques are also applied to GPS horizontal velocities with an average error of ±0.8 mm/a over the Chinese mainland and the surrounding areas, and the results show that the least-squares collocation method has the best performance, followed by the Kriging and multi-surface function methods. Furthermore, the edge effects of the spherical harmonics method are significantly affected by the sparseness and geometric distribution of the input data. In general, the least-squares collocation method is superior in terms of its robustness, edge effect, error distribution and stability, while the other methods have several positive features. [ABSTRACT FROM AUTHOR]

Through the measurement of resistivity, magnetic susceptibility, and Hall effect, we discovered a novel BiSe-based superconductor CaLaFBiSe with T of 3.9 K. A strong diamagnetic signal below T in susceptibility χ( T) is observed indicating the bulk superconductivity. The negative Hall coefficient throughout the whole temperature regime implies the dominant electron-type carriers in the sample. Different to most of BiS-based compounds where superconductivity develops from a semiconducting-like normal state, its resistivity in the present compound exhibits a metallic behavior down to T . Together with the enhanced T , the metallic character of the normal state implies that the electronic structure of CaLaFBiSe may be different to those in the other BiS-based compounds. [ABSTRACT FROM AUTHOR]

Lightweight reinforced thermoplastic (LWRT) is a newly developed porous material. The low density, high rigidity, design flexibility and sound absorption of LWRT facilitate its application in the automotive industry. Fibers are bonded with a matrix and air is imported by deconsolidation, which is not only economical but also environmentally friendly. In this work, film stacking and non-woven methods were employed as the impregnation techniques to manufacture LWRT. The molded thickness and surface density of LWRT were varied to study their influences on the structures and mechanical properties. Different lengths of fibers in LWRT were selected and 7 % PP-g-MAH was added to the matrix and compared with unmodified matrix. The mechanical properties decreased with the increase in molded thickness and the decrease in surface density. With higher fiber length, the strength and stiffness increased, while the toughness exhibited a maximum value at 80 mm fiber length. The strength and stiffness of LWRT were also enhanced when 7 % PP-g-MAH was added. [ABSTRACT FROM AUTHOR]

The brain ventricular system is essential for neurogenesis and brain homeostasis. Its neuroepithelial lining effects these functions, but the underlying molecular pathways remain to be understood. We found that the potassium channels expressed in neuroepithelial cells determine the formation of the ventricular system. The phenotype of a novel zebrafish mutant characterized by denudation of neuroepithelial lining of the ventricular system and hydrocephalus is mechanistically linked to Kcng4b, a homologue of the 'silent' voltagegated potassium channel a-subunit Kv6.4. We demonstrated that Kcng4b modulates proliferation of cells lining the ventricular system and maintains their integrity. The gain of Kcng4b function reduces the size of brain ventricles. Electrophysiological studies suggest that Kcng4b mediates its effects via an antagonistic interaction with Kcnb1, the homologue of the electrically active delayed rectifier potassium channel subunit Kv2.1. Mutation of kcnb1 reduces the size of the ventricular system and its gain of function causes hydrocephalus, which is opposite to the function of Kcng4b. This demonstrates the dynamic interplay between potassium channel subunits in the neuroepithelium as a novel and crucial regulator of ventricular development in the vertebrate brain. [ABSTRACT FROM AUTHOR]

The small-scale Balugou Cu-Pb-Zn skarn deposit (45 298 tonnages of ore at 0.1% to 3.99% Cu, 0.20% to 0.43% Pb and 0.76% to 10.92% Zn) is located in the Wulonggou area in the eastern Kunlun orogen, NW China. Ore deposition is spatially and temporally related with the pre-collisional Anisian Balugou granites (~244 Ma). The mineralization hosted by the contact between marble beds within the Paleo-Proterozoic Jinshuikou Group and Balugou granites, was structurally and lithologically controlled. The mineralogy of the Balugou deposit includes an early simple skarn mineral gangue (epidote with little diopside) and a late complicated quartz sulfide assemblage (pyrite, pyrrhotite, chalcopyrite, sphalerite, galena, bornite, quartz, carbonate and chlorite). The δS values of eighteen sulfides range from -2.1‰ to +2.8 ‰, with an average of +0.07‰, and the calculated δS values for HS in hydrothermal fluids range from -3.2‰ to +2.4‰, with an average of +0.03‰, suggesting a relatively homogeneous magmatic (±mantle) source, with sulfur produced directly by the Balugou granites. The sixteen sulfides have Pb/Pb ratios from 18.367 4 to 18.384 1, Pb/Pb ratios from 15.634 6 to 15.641 5, and Pb/Pb ratios from 38.455 5 to 38.485 0, which are close to those of K-feldspars from the Balugou granites, but are far away from age-corrected lead isotopic ratios of six wall-rock samples. So it was considered that the Pb sources of sulfides must be almost derived from the Balugou granites rather than the older wall-rocks. Collectively, it's suggested that the Balugou Cu-Pb-Zn deposit belongs to skarn deposit, and the sulfur and lead deposited in it were leached from the Anisian Balugou granites. [ABSTRACT FROM AUTHOR]

Real-time traffic flow forecasting is of great importance in the development of advanced traffic management systems and advanced traveler information systems. Traffic flow is evaluated using time series, and the Autoregressive Integrated Moving Average (ARIMA) model has been commonly used for determining the regression-type relationship between historical and future data. However, the performance of the ARIMA model is limited by the difficulty of capturing nonlinear patterns and the challenges of diagnosing permanent white noises. Hence, a hybrid method of ARIMA-EGARCH-M-GED was developed with the intent to address those limitations. It combines the linear ARIMA model with a nonlinear model of Exponent Generalized Autoregressive Conditional Heteroscedasticity (EGARCH) to capture heteroscedasticity (the variance of random error varying across the data) of traffic flow series. EGARCH in Mean (EGARCH-M), which corrects the expression of conditional variance by connecting the conditional mean directly with the variance, was introduced to better restrain the influence of abnormal data. Moreover, the tail of the generalized error distribution (GED) is better than that of the normal distribution in characterizing the features of time series, especially heteroscedasticity of residual sequences. Data collected from an interstate highway (I-80 in California) with a sampling period of 5 minutes were used to evaluate the performance of the proposed model. The results from the hybrid model were compared with ARIMA, an artificial neural network, and a K-nearest neighbor model. The results showed that the hybrid model outperformed the other methods in terms of accuracy and reliability. Overall, the proposed model performed well in tracking the features of measured data and controlling the impact of abnormal data. [ABSTRACT FROM PUBLISHER]

We have synthesized the superconducting KNaFeSe ( x = 0.07 and 0.25) crystal by using the flux technique. SEM images demonstrate that two samples consist of successive plate-like surfaces oriented into ab plane. EDS analysis yields the average compositions as (NaK)FeSefor x = 0.07 and (NaK)FeSe for x = 0.25. XRD pattern gives the ( 00 ℓ) peaks. The main peaks are indexed to the I4/ m space group corresponding to reflected intensities from (002), (006), (008), and (0010) planes related to the peaks of the phase KFeSe. The lattice parameters are calculated as a = 8.701(4) and c = 14.185(2) Å for x = 0.07, and a = 8.689(3) and c = 14.054(4) Å for x = 0.25. ZFC magnetization measurement exhibits a very sharp transition which indicates the presence of superconductivity in the crystal. The superconducting transition temperatures, T , obtained from magnetization measurements are estimated to be 31.0 and 28.4 K for x = 0.07 and 0.25, respectively. The critical current value, J (0), deduced from the M− H loops are approximately 2.8 ×10 A/cm for x = 0.07 and 2.87 ×10 A/cm for x = 0.25 at 5 K. The volume pinning force, F , of x = 0.07 sample is found larger than that of the x = 0.25 one. [ABSTRACT FROM AUTHOR]

The coal-bearing strata of the deep Upper Paleozoic in the GS Sag have high hydrocarbon potential. Because of the absence of seismic data, we use electromagnetic (MT) and gravity data jointly to delineate the distribution of deep targets based on well logging and geological data. First, a preliminary geological model is established by using three-dimensional (3D) MT inversion results. Second, using the formation density and gravity anomalies, the preliminary geological model is modified by interactive inversion of the gravity data. Then, we conduct MT-constrained inversion based on the modified model to obtain an optimal geological model until the deviations at all stations are minimized. Finally, the geological model and a seismic profile in the middle of the sag is analysed. We determine that the deep reflections of the seismic profile correspond to the Upper Paleozoic that reaches thickness up to 800 m. The processing of field data suggests that the joint MT-gravity modeling and constrained inversion can reduce the multiple solutions for single geophysical data and thus improve the recognition of deep formations. The MT-constrained inversion is consistent with the geological features in the seismic section. This suggests that the joint MT and gravity modeling and constrained inversion can be used to delineate deep targets in similar basins. [ABSTRACT FROM AUTHOR]

Gd-encapsulated carbonaceous dots (Gd@C-dots) hold great potential in clinical applications as a novel type of T1 contrast agent for magnetic resonance imaging (MRI). However, current synthetic methods require multiple purification steps due to poor size control, making them unsuitable for high throughput. Herein, a novel, mesoporous silica nanoparticle (MSN)-templated method for the size-controlled synthesis of Gd@C-dots is reported. Briefly, MSNs nanoreactors of different pore sizes are loaded with Gd precursors. Upon calcination, carbon layers are grown around the Gd cations. The spatial restraint of the silica cavity facilitates size control of the produced Gd@C-dots. Specifically, using 3, 7, and 11 nm MSNs as templates allows the synthesis of 3.0, 7.4, and 9.6 nm Gd@C-dots, respectively. A significant size impact on the magnetic and optical properties of the nanoparticles is shown, with the smallest Gd@C-dots showing the highest r1 relaxivity (10 mM−1 s−1) and fluorescence quantum yield (30.2%). The 3.0-nm Gd@C-dots were then conjugated with a tumor-targeting ligand, c(RGDyK), and injected into U87MG xenograft tumor models. Good tumor targeting was observed in T1-weighted MRI images; whereby the unbound nanoparticles were efficiently excreted through renal clearance, avoiding long-term toxicity to the host. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) density distribution of inhomogeneous dense deuterium tritium plasmas in laser fusion is revealed by the energy loss of fast protons going through the plasmas. The fast protons generated in the laser-plasma interaction can be used for the simulation of a plasma density diagnostics. The large linear and ill-posed equation set of the densities of all grids is obtained and then solved by the Tikhonov regularization method after dividing a 3D area into grids and knowing the initial and final energies of the protons. 3D density reconstructions with six proton sources are done without and with random noises added to the final energy. The revealed density is a little smaller than the simulated one in most simulated zones and the error is as much as those of 2D reconstructions with four proton sources. The picture element N is chosen as 2744 with consideration of smoothness and calculation memory of the computers. With fast calculation speed and low error, the Tikhonov regularization method is more suitable for 3D density reconstructions with large calculation amount than simultaneous iterative reconstruction method. Also the analytical expressions between the errors and the noises are established. Furthermore, the density reconstruction method in this paper is particularly suitable for plasmas with small density gradient. The errors without noises and with 2% noises added to the final proton energies are 3 and 20%, respectively, for the homogeneous plasma. [ABSTRACT FROM AUTHOR]

Unconventional superconductors are characterized by various competing ordering phenomena in the normal state, such as antiferromagnetism, charge order, orbital order or nematicity. According to a widespread view, antiferromagnetic fluctuations are the dominant ordering phenomenon in cuprates and Fe based superconductors and are responsible for electron pairing. In contrast, charge order is believed to be subdominant and compete with superconductivity. Here, we argue that fluctuating charge order in the (0,π) direction is a feature shared by the cuprates and the Fe based superconductors alike. Recent data and theoretical models suggest that superconductivity is brought about by charge order excitations independently from spin fluctuations. Thus, quantum fluctuations of charge order may provide an alternative to spin fluctuations as a mechanism of electron pairing in unconventional superconductors. [ABSTRACT FROM AUTHOR]

A copper-catalyzed intramolecular amidation of unactivated C(sp3)−H bonds to construct indoline derivatives has been developed. Such an amidation proceeded well at primary C−H bonds preferred to secondary C−H bonds. The transformation owned a broad substrate scope. The corresponding indolines were obtained in good to excellent yields. N-Formal and other carbonyl groups were suitable and were easily deprotected and transformed into methyl or long-chained alkyl groups. Preliminary mechanistic studies suggested a radical pathway. [ABSTRACT FROM AUTHOR]

Isomer is sometimes fundamental to the formation of the resulting compounds. The design and preparation of coordination compounds based on isomers is of tremendous paramount since they have a lot in common but simultaneously some difference, which can lead to variation of both the topologies and properties. Solvothermal reactions of Hn-pytza (n = 3, 4) with Co(ClO)·6HO, afforded two interesting coordination polymers, one dimensional [Co(3-pytza)(HO)]·2nHO ( 1) and three dimensional [Co(4-pytza)] ( 2), where Hn-pytza = 5-( n-pyridyl)tetrazole-2-acetic acid (n = 3, 4). The thermal decomposition behavior of the two compounds were characterized by the differential scanning calorimetry (DSC) and thermogravimetric-differential thermogravimetric (TG-DTG), showing [Co(4-pytza)] is superior to [Co(3-pytza)(HO)]·2nHO in terms of energetic performance. Furthermore, the entropy of activation (∆S), enthalpy of activation (∆H), and free energy of activation (∆G) were calculated, as well. [ABSTRACT FROM AUTHOR]