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A bipyridyl-based Mn2+-organic framework was synthesized. Activated Mn-MOF-1 could serve as an efficient heterogeneous catalyst for the cycloaddition of CO2 with epoxides and Knoevenagel condensation reactions.

This article studies the problem of multiobjective control design for a class of human–machine systems (HMSs) with safety performance constraints containing state constraints and input constraints. The HMSs under consideration not only monitor the human but also need to take proper actions to both the human and machine. A model of controlled hidden Markov jump system (CHMJS) is applied to represent the HMSs. Based on the CHMJS model, a sufficient condition for the practical mean square stability of the unconstrained HMSs is first derived using a stochastic Lyapunov functional. A sufficient condition for ensuring the safety performance constraints of the HMSs is also deduced by employing reachability analysis and set invariance theory. Subsequently, a bilinear matrix inequality-based control design is presented to guarantee both the practical mean square stability and safety performance constraints of the HMSs. A multiobjective optimization problem (MOP) is then formulated to determine a feedback controller for the human and a human-assistance controller for the machine such that both the practical mean square stability and safety performance constraints as well as the less human intervention can be satisfied. An algorithm that mixes the multiobjective particle swarm optimization and linear matrix inequality technique is developed to solve this MOP. Finally, a lane departure example is given to illustrate its effectiveness.

Given a tree T and a vertex v in T , the number of subtrees of T containing v is denoted by η T ( v ) and called the subtree number at v . Similarly, η T ( u , v ) denotes the number of subtrees of T that contain both u and v . Motivated from the distance function and the eccentricity at a vertex, we study the eccentric subtree number at a vertex v in T , defined as η T e c c ( v ) = min u ∈ V ( T ) η T ( v , u ) . This concept provides us a new perspective in the study of the well-known correlation between the distance and the subtree numbers. We will present properties of the eccentric subtree number analogous to those related to the eccentricity and center of a tree, as well as some extremal results with respect to the eccentric subtree number and sum of eccentric subtree numbers in a tree. Some open problems for further study are also proposed.

A new family of isostructural 3d–4f heterometallic metal–organic frameworks (HMOFs), [Zn3EuxTb2−x(TZI)4(DMA)5(H2O)3]·4DMA [x = 0 (1), 0.3 (2), 0.6 (3), 0.9 (4), 1 (5), 1.2 (6), 1.5 (7), 1.8 (8), 2 (9)], has been synthesized using the 5-(4-(tetrazol-5-yl) phenyl)isophthalic acid (H3TZI) ligand, LnIII ions and ZnII ions under solvothermal conditions. All HMOFs exhibit a (3,3,4,5,5)-connected 63·63(42·62·82)(4·65·8)(4·66·83) topology, which features three different types of motifs: one is a mononuclear ZnII ion and the other two motifs are binuclear [Zn(COO)3Ln] clusters. The adsorption experiments indicate that Zn3Tb2 (1) could efficiently remove almost all I2 from cyclohexane solution after 12 h and also showed better adsorption towards neutral red (NR) dye (adsorption: only the Zn3Tb2 (1) was taken as one representative). Simultaneously, the luminescence sensing showed that Zn3Tb2 (1) and Zn3Eu2 (9) have excellent response and sensitivity towards pollutants such as Fe3+ ions and 2,4,6-trinitrophenol (TNP) with high selectivity and a fairly low limit of detection through luminescence quenching effect. Moreover, seven trimetallic-doped HMOFs 2–8 analogues of Zn3Ln2 (single) HMOFs were designed and prepared, showing different changes of luminescent color. More interestingly, Zn3Eu1.5Tb0.5 (7) with white-light emission was fabricated by doping relative concentrations of Eu3+ and Tb3+ ions. To the best of our knowledge, Zn3Eu1.5Tb0.5 (7) represents a novel kind of heterometallic Zn3Ln2 HMOFs with white-light emission. It could be deduced that the excellent characteristics, namely strong typical luminescence emission of ZnII and LnIII ions, microporous channels, active open metal sites (tetra-coordinated ZnII–metal sites), and uncoordinated carboxylate O atoms and uncoordinated tetrazolate N atoms, made the above HMOFs an ideal platform for adsorption, luminescence sensing, and white-light emission. More significantly, these HMOFs are the first reported Zn–Ln heterometallic materials with the H3TZI ligand.

The purpose of this study is to establish a molecular method to identify Xanthii Fructus and two adulterants, the fruits of Xanthium mongolicum and X. italicum. Xanthii Fructus is the fruit of X. sibiricum, which is a Chinese herbal medicine used clinically to treat allergic rhinitis. The fruits of X. mongolicum and X. italicum have strong morphological similarities with Xanthii Fructus, while their safety of medication cannot be guaranteed. The genomes of X. sibiricum, X. mongolicum, and X. italicum were sequenced, which generated sequences of 2.21, 2.24, and 2.54 Gb, respectively. Based on the 76 specific contigs screened out by BLASTN and Bowtie 2, the corresponding primers were designed by Primer 5.0. Three pairs of primers with stable amplification efficiency and good reproducibility were screened out to establish a multiplex PCR method based on the PCR amplification results. Further, the annealing temperature, the amount of DNA template, the number of cycles, different DNA polymerases, and different PCR thermal cyclers were optimized. Fragments of 262 bp and 458 bp from X. sibiricum, 260, 454, and 927 bp from X. mongolicum, and 260 bp and 926 bp from X. italicum were amplified under the following conditions: the annealing temperature of 52 ℃, 35 cycles, 30 ng template DNA. Then, the established method was used to detect 18 samples of X. sibiricum, 17 samples of X. mongolicum, and 12 samples of X. italicum. The results showed that all the samples had positive results, which were consistent with the morphological identification results, thus proving the stability and reliability of the established method. Combining genome sequencing technology and multiplex PCR method to identify Xanthii Fructus and its adulterants can not only obtain the difference in genetic background but also facilitate the design of reliable primers. The multiplex PCR have high specificity and repeatability, providing a new method for the molecular identification of Xanthii Fructus.

Background. Osteoporosis (OP) associated with knee osteoarthritis (KOA) is common in older men and postmenopausal women, and it is important to find reliable and effective treatments for this disease to improve joint function and bone metabolism in this population. Objective. To clarify the clinical efficacy of glucosamine (GlcN) plus sodium hyaluronate (SH) for OP complicated by KOA (OP + KOA) and its influence on joint function and bone metabolic markers (BMMs). Methods. Admitted from July 2019 to July 2021, 126 patients with OP + KOA were selected, including 76 cases (observation group) treated with GlcN plus SH and 50 cases (control group) given GlcN alone. The pain, joint function, BMMs, and clinical efficacy were evaluated and compared. Pain and joint function assessments employed the Visual Analogue Scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) plus Lysholm Knee Scoring Scale, respectively. BMMs mainly measured bone gla protein (BGP), serum tartrate-resistant acid phosphatase variant (TRACP)-5b, type I collagen cross-linked C-telopeptide (CTX-1), and bone-specific alkaline phosphatase (BALP). Results. Higher posttreatment VAS scores were determined in observation group as compared to control group; observation group showed lower WOMAC scores of joint function and higher Lysholm scores than control group; in terms of BMMs, TRACP-5b and CTX-1 were lower while BGP and BALP were higher in observation group; the curative effect was also higher in observation group. All the above differences were statistically significant. Conclusions. GlcN plus SH has definite clinical efficacy in the treatment of OP + KOA, which can not only significantly improve patients’ joint function and bone metabolism but also relieve pain, with high clinical popularization value.

A systematic study was carried out on the antioxidants in miracle fruit leaf extract. The total phenols, total flavonoids, saponins and the antioxidant activities of the extract were evaluated usin...

This article investigates a fuzzy boundary control problem of a class of stochastic nonlinear systems modeled by the Ito-type parabolic stochastic partial differential equation (SPDE). Initially, a Takagi–Sugeno fuzzy SPDE model is proposed to accurately represent the nonlinear SPDE system. Then, on the basis of the infinite-dimensional infinitesimal operator, a fuzzy boundary static output feedback controller is developed in terms of a set of linear matrix inequalities to locally exponentially stabilize the resulting system in the mean square sense. By using an approximation argument and constructing a Lyapunov function for the mild solution, the local mean square exponential stability of the closed-loop system is proved. Meanwhile, the closed-loop well-posedness analysis is also given by virtue of the semigroup theory. Finally, a simulation study on a Belousov–Zhabotinsky reaction–diffusion system with random parameter variation is presented to illustrate the effectiveness of the proposed method.

Six new two-dimensional isostructural lanthanide coordination polymers (LnIII-CPs), [Ln2(L)3(H2O)3]·DMF (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5) and Ho (6), H2L = 3-(3,5-dicarboxylphenoxy)pyridine), have been fabricated successfully under solvothermal conditions. In these compounds, LnIII ions are linked by the mixed (μ-Ocarboxylate)(COO)2 triple bridges to give dinuclear motifs. The motifs are connected through single carboxylate bridges to give alternating chains, and the chains are interlinked by the L ligands to produce 2D layers. Their structures with accessible Lewis-base sites and coordinated water molecules could easily recognize various analytes. The dc magnetic susceptibility studies for Gd-CP (3) and Ho-CP (6) reveal the occurrence of probable antiferromagnetic interactions, but for Dy-CP (5) show ferromagnetic interactions. Further investigations suggest that Dy-CP (5) displays slow magnetic relaxation behavior with an energy barrier (ΔUeff) and a pre-exponential factor (τ0) of 25.47 K and 1.25 × 10−6 s at 1200 Oe dc field, respectively. The luminescence explorations suggest that Eu-CP (2) and Tb-CP (4) can exhibit high quenching efficiency and low detection limit for sensing Fe3+, MnO4−, CrVI-anions (CrO42−, Cr2O72−) and 2,4,6-trinitrophenol (TNP) in water systems. Moreover, in the process of detecting analytes, Eu-CP (2) and Tb-CP (4) not only exhibit excellent water stability and strong luminescence, but also show remarkable recyclability and regeneration. Especially, Eu/Tb-CP can detect Fe3+, MnO4−, CrO42− and Cr2O72− simultaneously, which is rarely reported in the past.

Three 3D lanthanide metal–organic frameworks (Ln-MOFs), [Pr4(L)4(H2O)8]·10H2O (1), [Gd(L)(CH3COOH)0.5]·0.5H2O (2), and [Dy(L)(H2O)2]·H2O (3), H3L = biphenyl-3′-nitro-3,4′,5-tricarboxylic acid, have been synthesized by solvothermal methods and their structures and magnetic properties were fully characterized. The Pr-MOF (1) contains unique linear-like tetranuclear clusters with triple and double carboxylate bridges. The tetranuclear clusters are cross-linked by L backbones to form a 3D framework, and it represents a rare (3,3,12)-connected net with the point symbol (43)(43)(421·625·818·102). The Gd-MOF (2) is a layer-pillared 3D framework in which the layers with (μ-COO)2(μ2-Ocarboxylate) triple bridges and single carboxylate bridges are interlinked by the L ligands. The Dy-MOF (3) is constructed from 1D uniform chain units with (μ-COO)2 double bridges. Adjacent chains are connected by the L ligands into a 3D framework. Magnetic investigations on these MOFs have been carried out and revealed that the different carboxylate bridges are antiferromagnetic in the Pr-MOF (1) and Dy-MOF (3) but ferromagnetic in the Gd-MOF (2). Furthermore, the Dy-MOF (3) also shows slow magnetic relaxation behaviors under a zero dc field.

Five novel 3D anionic CoIILnIII heterometallic organic frameworks (HMOFs) [(CH3)2NH2]4[Co3Ln3(OH)(TZI)6(H2O)6]·2DMA·16H2O (CoLn, Ln = Eu (1), Gd (2), Tb (3), Dy (4), Ho (5), H3TZI = 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid) have been synthesized under solvothermal conditions and structurally characterized by elemental analysis, FTIR, PXRD, TGA and single-crystal X-ray diffraction. Structure analyses show that these CoLn HMOFs (1–5) are isomorphous and contain two different metal motifs: one is a triangular trinuclear Co3(μ3-OH)(μ2-tetrazolate)6 cluster, and the other is a linear trinuclear Ln3(COO)12 cluster. The adjacent CoII and LnIII clusters are connected by the TZI ligands to give a 3D heterometallic framework with a (3,3,6,10)-connected (4·6·8)(42·5)(43·53·64·85)(47·510·66·78·810·94) topology. Magnetic investigations indicated that CoDy (4) and CoHo (5) display slow magnetic relaxation behaviors under a zero dc field. The most intriguing feature is that these CoLn HMOFs (1–5) contain microporous structures with [(CH3)2NH2]+ cations being located in channels, which can successfully separate MB+ cationic dye molecules from mixed dye molecules including Rh B+, BV14+, NR0 and MO− (adsorption – take CoTb (3) as an example). At equilibrium, the removal percentage of MB+ with CoTb (3) in a mixture of dyes is about 97.5% and the mechanism of adsorption of MB+ is also explored. Such 3d–4f anionic HMOFs are unusual.

This paper studies the reachable set estimation problem of a class of human-in-the-loop (HiTL) control systems described by a controlled hidden Markov jump model. Our aim is to determine an ellipsoid-like set which bounds all the machine state trajectories of the HiTL system under zero initial condition. By using a stochastic Lyapunov functional, a reachable set estimation condition is established, which is provided in terms of a set of matrix inequalities. Finally, an example is given to show the effectiveness of the proposed result.

In this study, the embryonic development of Syngnathus schlegeli is first described based on external morphological characteristics and then the genetic relationship between embryos is investigated using a microsatellite-based approach. Embryonic development proceeds from fertilized egg to prerelease of larva and can be categorized into four periods: early embryogenesis, eye development, snout formation and larva, which can be further divided into 15 stages. Embryos in the brood pouch are all in the same developmental stage. However, multi-maternity is observed in all sampled broods. Microsatellite-based parentage analysis suggests that pregnant males had, per male, mated with and received eggs from 3 to 7 females, with average being 4.3. The embryos of full sibs within a brood pouch were clustered, and seven patterns of parentage were observed. Combining previous studies with the evidence obtained from genotyped eggs inside the brood pouch in this study, we can confirm that the mating pattern of S. schlegeli is polygamous.

Seven new water-soluble chiral/achiral SOD-mimicking metal complexes: NaK[Mn(R-L1)(C2H5OH)4] (Mn-1a), NaK[Mn(S-L1)(C2H5OH)4] (Mn-1b), NaK[Co(R-L1)]·3H2O (Co-2a), NaK[Co(S-L1)]·3H2O (Co-2b), NaK[(VO)(R-L1)(OH)]·5H2O (V-3a), NaK[(VO)(S-L1)(OH)]·5H2O (V-3b) and [MnL2]·[(CH3CH2)3NH]2·5H2O (Mn-4) were synthesized and fully characterized. Furthermore, hybrid protein, binding with complexes and bovine serum albumin (BSA) to enhance the antioxidant activity, were synthesized and evaluated by multispectroscopic techniques. The SOD activities of all complexes and their corresponding hybrid proteins were tested by xanthine/xanthine oxidase method, the antioxidant activity of them were determined by ABTS method. The results show that the SOD activities of the hybrid proteins are higher than that of the corresponding complexes. From the values of the antioxidant activity we obtained, there seems to be some connection between the configuration and antioxidant activity.

A novel metal–organic framework, [H2bpy]0.5[Cd3(OH)(L)2(bpy)(H2O)2]·(bpy)0.5·2H2O (1) (H3L = 3-(3,5-dicarboxylphenyl)-4-carboxylpyridine, bpy = 4,4′-bipyridine), with blue luminescence, was successfully synthesized under solvothermal conditions. Structure analysis indicates that this compound is composed of triangle [Cd3(μ3-OH)] clusters linked by L ligands, forming a novel 3D framework with a (3,3,8)-connected (42·6)(42·6)(44·55·64·78·87) topology. Cd-MOF-1 contains microporous channels with accessible Lewis-base sites (N), uncoordinated carboxylate groups and coordinated H2O molecules, which are easy to recognize various small molecules. Meanwhile, this compound exhibits a microporous structure with [H2bpy]2+ cations being located in the channels, which can be easily replaced by some cationic dyes. Particularly, Cd-MOF-1 displays high water and pH stability. Based on the aforementioned considerations, when Cd-MOF-1 was immersed in the different metal ion aqueous solutions and different nitro explosive EtOH solutions, it performed as a highly selective and sensitive sensor for Fe3+ ions and TNP (2,4,6-trinitrophenol). Moreover, the probable sensing mechanism was also investigated in detail. More interestingly, dye adsorption studies revealed that Cd-MOF-1 can adsorb cationic dyes in aqueous solution while the anionic and neutral dyes cannot be absorbed and the cationic dye adsorption amounts decrease with the increase in dye size. Therefore, Cd-MOF-1 can potentially act as a column-chromatographic filter for the separation of dye molecules.

Six new 3D isomorphous lanthanide metal organic frameworks (Ln-MOFs), [Ln2(L)2(DMF)2(H2O)4]·H2O·DMF (Ln = Pr (1); Sm (2); Eu (3); Gd (4); Dy (5); Ho (6)); H3L = 5-(2-nitro-4-carboxylphenyl)isophthalic acid, have been solvothermally synthesized and characterized. Crystallographic studies revealed that these MOFs were isomorphous 3D frameworks in which the dinuclear units with double (μ-COO)2 bridges were interlinked by the L ligands. They represent the (3,6)-connected (42·6)(43·68·82·10·12) topology. The magnetic coupling through double carboxylate bridges is antiferromagnetic in Pr-MOF (1), Gd-MOF (4), Dy-MOF (5) and Ho-MOF (6). Furthermore, Dy-MOF (5) shows slow magnetic relaxation behaviors under zero dc field. The luminescence sensing experiments demonstrated that Eu-MOF (3) displayed highly selective, well-recyclable properties and a low detection limit for sensing alkylamines in water systems. The study of Ln-MOF sensing for alkylamines is very scarce.

Two luminescence coordination polymers (CPs) formulated as {[Zn(L)(H2O)2]·H2O}n (1) and {[Cd(L)(H2O)2]·4H2O}n (2) are successfully prepared by solvothermal reactions between the corresponding metal(II) ions and 5-(4-pyridylamino)isophthalic acid (H2L). Crystallographic studies reveal that 1 and 2 exhibit similar 2D honeycomb layer networks, but have different numbers of lattice water molecules. The layers are connected through hydrogen bonds to give 3D supramolecular frameworks. CPs 1 and 2 possess coordinated water molecules and uncoordinated oxygen atoms as well as electron-rich amide groups, which are easy to recognize diverse analytes. Moreover, they show considerable stability in aqueous systems with a broad pH range from 3 to 12. Luminescence sensing experiments indicate that they can be regarded as highly sensitive sensors for detecting Fe3+ ions, CrVI anions (CrO42− and Cr2O72−) and 2,4,6-trinitrophenol (TNP) through luminescence quenching. In addition, the mechanisms for the luminescence response of CPs 1 and 2 towards Fe3+ ions, CrVI anions and TNP have been investigated in detail. Besides, CPs 1 and 2 represent two very good examples of versatile Zn/Cd-CP probes capable of sensing Fe3+ ions, CrVI anions and TNP.

Four new three-dimensional Mn(II) coordination polymers with two isomeric ligands, 5-(3-nitro-4-carboxylphenyl)isophthalic acid (H3L1) and 5-(2-nitro-4-carboxylphenyl)isophthalic acid (H3L2), have been prepared and structurally and magnetically characterized. They are of the formula [Mn(HL1)(CH3CN)] (1), [Mn(L2)]·H2O·H3O (2), [Mn3(L2)2(DMF)2]·H2O (3), [Mn4(HL2)4(H2O)5]·2H2O (4). Compounds 1–3 contain diverse alternating magnetic chain’s sequences in which the chains are linked by the organic spacers into 3D structures. In 1, the two double [(μ-Ocarboxylate)2 and (μ-syn-anti-COO)2] bridges with apparently different structural parameters alternate in the − ABAB − sequence. While in 2, the two sets of double μ-syn-anti-carboxylate bridges with slightly different structural parameters also alternate in the -ABAB- sequence. In 3, the double (μ-syn-anti-COO)2 bridges and (μ-ODMF)(μ-syn-anti-COO)(μ3-COO) triple bridges alternate in the -ABB- sequence. Compound 4 contains two sets of independent motifs: one is 1D chain based on three different double (μ-syn-anti-COO)2 bridges alternate in the -ABC- sequences; the other is 1D tape-like motifs with three different single μ-syn-anti-COO bridges. Two sets of motifs in 4 are alternately linked together by the organic backbones into a complicated 3D structure. Compounds 1, 2 and 4 exhibit weak antiferromagnetic couplings. A magnetostructural survey indicates that the antiferromagnetic coupling through the (μ-syn-anti-COO)2 bridges decreases as the Mn⋯Mn distances increases and the magnitude of antiferromagnetic coupling mainly depends on the Mn O Mn angle for the double (μ2-Ocarboxylate)2 bridges.

This article studies the problem of synthesis with guaranteed cost and less human intervention for linear human-in-the-loop (HiTL) control systems. Initially, the human behaviors are modeled via a hidden controlled Markov process, which not only considers the inference's stochasticity and observation's uncertainty of the human internal state but also takes the control input to human into account. Then, to integrate both models of human and machine as well as their interaction, a hidden controlled Markov jump system (HCMJS) is constructed. With the aid of the stochastic Lyapunov functional together with the bilinear matrix inequality technique, a sufficient condition for the existence of human-assistance controllers is derived on the basis of the HCMJS model, which not only guarantees the stochastic stability of the closed-loop HiTL system but also provides a prescribed upper bound for the quadratic cost function. Moreover, to achieve less human intervention while meeting the desired cost level, an algorithm that mixes the particle swarm optimization and linear matrix inequality technique is proposed to seek a suitable feedback control law to the human and a human-assistance control law to the machine. Finally, the proposed method is applied to a driver-assistance system to verify its effectiveness.

Kakkalide, a compound obtained from a traditional Chinese medicine Puerariae flos, has been shown significant anti-ischemia activity in animal experiments recently. However, the solubility of the compound need to be enhanced with hydroxypropyl-β- cyclodextrin, which is a strong controversial solution adjuvant via intravenous administration. Methylamine irisolidone is a structurally modified kakkalide with good solubility in the water. In this study, the effect of this new compound on acute myocardial ischemia in dogs was investigated. The results showed that methylamine irisolidone (80 mg/kg, i.v) could reduce the myocardial infarct areas in dogs with myocardial infarction. The serum lactate dehydrogenase (LDH) activity and MB isoenzyme of creatine kinase (CK-MB) were suppressed by methylamine irisolidone after 240 min of administration. These results suggested that methylamine irisolidone exerts the protective effects on myocardial ischemia injury, which may be due to its function of inhibiting LDH and CK-MB releasing, stabilizing myocardial cell membrane and improving myocardial microcirculation and metabolism.