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Two new borates, NaK1.5[B{B5O9(OH)}{B5O8(OH)2}1/2] (1) and Na3.5[Al{B3O6(OH)}{B5O10}1/2{BO(OH)}] (2), have been made by a solvothermal method. Structure 1 is made of two types of oxoboron clusters ([B5O9(OH)]4− and [B5O8(OH)2]3−) and BO4 tetrahedra to form a 3D porous layer, in which the [B5O9(OH)]4− clusters are bridged by BO4 groups to produce a 2D B–O layer with 11-membered ring (MR) windows, while the [B5O8(OH)2]3− clusters as 2-connected pillars join the adjacent B–O layers to make a 3-D porous layer. Structure 2 is built from two types of oxoboron clusters ([B3O6(OH)]4− and [B5O12]9−), AlO4 units and BO2(OH) triangles to produce 3D pillar-layered aluminoborate (ABO), in which the [B5O12]9− clusters are linked together to form a 2-D B–O layer; the [B3O6(OH)]4− clusters and AlO4 groups join each other to form 1D tubular ABO; and the BO2(OH) triangles act as linkers to connect the adjacent B–O layer and the ABO tubes, resulting in 3D pillar-layered ABO. Interestingly, the ABO tubes decorated with the BO2(OH) triangles act as pillars to make a 3D layer-pillared structure. UV-vis diffuse spectra indicate that both have cut-off edges below 190 nm, and the calculated band gaps are 5.75 and 5.78 eV, respectively. [ABSTRACT FROM AUTHOR]

This paper addresses the scheduling problem arising from refueling multiple geosynchronous (GEO) satellites with multiple servicing vehicles [many-to-many (M2M) refueling]. The problem is defined by a set of potential fuel tanker locations, a homogeneous fleet of servicing vehicles with limited capacities, and a set of fuel-deficient GEO satellites with known fuel demands. The objective is to open a subset of fuel tankers, to assign GEO satellites to these tankers and to design vehicle servicing sequences, in order to minimize the total mission costs. To achieve such an economical refueling strategy, the fuel tanker location and routing decision are required to be determined simultaneously. It is shown that this problem can be formulated as a location-routing problem (LRP) which is obviously NP-hard. In order to solve it, an ant colony optimization (ACO) metaheuristic that features a special solution representation scheme is proposed. The proposed algorithm is then tested on two types of instances depending on whether the cost for opening a fuel tanker is considered or not. Numerical experiments show that both the consideration of the fuel tanker opening costs and their locations do affect the refueling schedule. Furthermore, the proposed algorithm outperforms the existing approaches in the M2M refueling mission design, and it is able to detect the optimal refueling strategy on all instances containing 85 GEO targets with 15 potential fuel tankers while previous works stopped at 15 satellites and 2 fuel tankers. • Scheduling of the multiple satellites refueling mission is presented. • Servicing vehicle routing and the fuel tanker location are considered simultaneously. • An ant colony optimization based solving methodology is proposed. • A special solution presentation scheme is applied to improve the computational burden. [ABSTRACT FROM AUTHOR]

Abstract The ninth edition of the China Trajectory Optimization Competition (CTOC9) considered the problem of navigation augmentation over a set of Chinese cities, wherein the competitors were expected to design a suitable LEO constellation to obtain the required navigation performance with the aim of minimizing overall system cost. In addition, an economical deployment strategy was also considered. The synthesis methods used by the Xi'an Satellite Control Center (XSCC) are described, along with the promising solution found by the team. Firstly, two techniques, feasible region based reduction and coverage region based reduction, are applied in sequence to narrow the search space. Then, the optimal constellation configuration is obtained through an Differential Evolution Algorithm (DE). Finally, a series of maneuver strategies are searched to inject each navigation satellite from a given initial carrying orbit to its target location. The solution obtained during the competition ranked third, and the improved one, found after the deadline, got the outstanding prize. [ABSTRACT FROM AUTHOR]

We present a study of the transfer orbits connecting landing points of irregular-shaped asteroids. The landing points do not touch the surface of the asteroids and are chosen several meters above the surface. The ant colony optimization technique is used to calculate the multiple-hopping trajectories near an arbitrary irregular asteroid. This new method has three steps which are as follows: (1) the search of the maximal clique of candidate target landing points; (2) leg optimization connecting all landing point pairs; and (3) the hopping sequence optimization. In particular this method is applied to asteroids 433 Eros and 216 Kleopatra. We impose a critical constraint on the target landing points to allow for extensive exploration of the asteroid: the relative distance between all the arrived target positions should be larger than a minimum allowed value. Ant colony optimization is applied to find the set and sequence of targets, and the differential evolution algorithm is used to solve for the hopping orbits. The minimum-velocity increment tours of hopping trajectories connecting all the landing positions are obtained by ant colony optimization. The results from different size asteroids indicate that the cost of the minimum velocity-increment tour depends on the size of the asteroids. [ABSTRACT FROM AUTHOR]

Two new metal borates, K[BO(OH)]·Hen ( 1, en = enthylenediamine) and NaCsBa[BO(OH)]·4(OH) ( 2) have been synthesized under solvothermal conditions. Their structures were determined by the single crystal X-ray diffraction and were further characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and powder X-ray diffraction, respectively. 1 crystallizes in the triclinic system, P-1 space group, a = 7.7152(6), b = 8.4057(6), c = 12.1319(10) Å, α = 92.505(6), β = 98.944(7), γ = 103.825(6)°, Z = 2. 2 crystallizes in the orthorhombic system, Pmn2 space group, a = 12.6972(6) Å, b = 13.7037(6) Å, c = 9.4968(5) Å, Z = 2. Compound 1 consists of isolated [BO(OH)] clusters which are held together through H-bonding interactions and K atoms to form a 3-D supramolecular framework. For 2, bowl-like isolated [BO(OH)] clusters were linked together to form a 3-D framework by different metal ions and H-bond system. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal reactions of 1-aminoethylidenediphonic acid { CH3C(NH2)(PO3H2)2, H4aedp} with CaCl2, Sr(NO3)2 and Pb(AC)2·3H2O resulted in three new main group metal diphosphonate coordination polymers. Namely, Ca[CH3C(NH3)(PO3H)2]2[CH3C(NH3)(PO3H)(PO3H2)]2 (1), Sr[CH3C(NH2) (PO3H)2(H2O)]·H2O(2) and Pb[CH3C(NH3)(PO3H)(PO3)]·H2O(3). The calcium (II) ion in complex 1 is octahedrally coordinated by six phosphonate oxygen atoms from six diphosphonate ligands, four of them in a bidentate and two in a monodentate fashion. The neighboring calcium ions are linked by pairs of P–O–P bridges, resulting in a pseudo-one-dimensional chain along the c axis. Complex 2 is the first example of the strontium phosphonate which has not been synthesized and structurally characterized before. It features a layered structure, in which strontium(II) ions are eight coordinated by an aqua ligand and seven phosphonate oxygen atoms from four diphosphonate ligands, two SrO8 polyhedra are bridged into a demeric unit by a pair of oxygen atoms and two diphosphonate groups. And such dimers are interconnected by the P–O–P bridges and O bridges to form complicated layers parallel to the ab plane. Complex 3 also has a layered structure in which the lead (II) ions are six coordinated by six phosphonate oxygens from four equivalent diphosphonate ligands. Each pair of PbO6 octahedra forms a dimeric unit via O–O edge-sharing and such dimeric units are interconnected via O–O edge-sharing to form a one-dimensional chain along the b-axis. These 1D chains are further bridged by the phosphonate ligands to form a complicated layer parallel to the bc plane. This type of layered structure has not been reported in other lead phosphonates. [Copyright &y& Elsevier]

Abstract: To identify genes and pathways not previously implicated in the mesenchymal–epithelial (M/E) interactions that are critical for normal mouse prostate development, we constructed six serial analysis of gene expression (SAGE) libraries. Bioinformatic analyses revealed expression of various members of numerous signalling pathways and the differential expression of several members of the wingless-related MMTV integration site (Wnt) signalling pathway. This pathway has not been previously implicated in prostate development thus expression of selected Wnt pathway members in the developing prostate was confirmed by RT-qPCR. Of particular interest, an antagonist of the Wnt pathway, secreted frizzled related protein 2 (Sfrp2), was highly expressed in the early prostate libraries and down regulated at later developmental stages. The expression levels of four Wnt ligands reported to interact with Sfrp2 were, therefore, examined by RT-qPCR. We found that only Wnt4 transcripts were detectable in the developing prostate. Expression of Sfrp2 was validated using RT-qPCR and localization of Sfrp2 transcripts and protein was carried out using in situ hybridization and immunofluorescence, respectively. These studies provide the first evidence that Wnt pathway members are expressed in the developing prostate. Functional analyses are now required to establish the biological significance of this observation. [Copyright &y& Elsevier]

This article introduces the basic principles of four kinds of inerters applied for structural vibration control including a traditional inertial mass damper and ideal clutch inerter damper. The clutch inerter damper with all damping (clutch inerter damper_all damped) and clutch inerter damper with partial damping (clutch inerter damper_part damped) are distinguished in detail. First, a series of energy indexes are defined for further analysis. Second, the control effect of displacement for the uncontrolled structure and the four inerter-based single-degree-of-freedom systems are compared. Finally, considering the total input energy (E 1) and the invalid damping energy (E CID_ric) as the effective indexes, combined with a large number of numerical simulation results, the variation rules of the two energy indexes with respect to two key parameters (inertia mass ratio and additional damping) are summarized, and the optimal parameters are proposed. The effectiveness of the optimal value is verified by displacement comparison. [ABSTRACT FROM AUTHOR]

The fluorescent flexible sensor for point-of-care quantification of clinical anticoagulant drug, Heparin (Hep), is still an urgent need of breakthrough. In this research, a hyperbranched poly(amido amine) (HPA) was decorated with tetraphenylethene (TPE) and Rhodamine B (RhB), constructing a ratiometric fluorescent sensor (TR-HPA) for Hep. When the sensor was exposed to Hep, the TPE units within the probe skeleton would aggregate, resulting in an increasing fluorescent emission at 483 nm. The 580 nm of fluorescence came from RhB enhance, simultaneously, due to the fluorescence resonance energy transfer. As a result, there are two good linear correlation between the fluorescence emission ratio (E 483 /E 580) of TR-HPA and the Hep concentration over a range of 0–1.0 μM, with a low limit of detection of 3.0 nM. Furthermore, we incorporate the TR-HPA probe into a polyvinyl alcohol (PVA) hydrogel matrix to create a flexible fluorescent sensing system platform, denoted as TR-HPA/PVA. This approach offers a straightforward visual detection method by causing a fluorescence color change from pink to blue when trace amounts of Hep are present. The hydrogel-based fluorescent sensor streamlines the detection procedures for Hep in biomedical applications. It shows great potential in rapid and point-of-care human blood clotting condition monitoring, making it suitable for next-generation wearable medical devices. ➢ Immobilized rhodamine B labelled AIE-featured hyperbranched poly(amido amine) in PVA matrix, a flexible fluorescent hydrogel was formed and applied for rapid detection of Hep with an obvious pink-to-blue fluorescent color change. [Display omitted] • A ratiometric fluorescent sensor for Hep was created by adorning HPA with TPE and RhB units. • A new flexible fluorescent hydrogel was formed by immobilized TR-HPA in PVA matrix. • The color of flexible fluorescent hydrogel changes from pink to blue upon exposure to Hep. • The flexible fluorescent hydrogel can be reusable more than 4-times cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quantitatively CO 2 -responsive, ratiometric fluorescence sensor synergizing TPE and Au NCs was firstly reported. • Water-soluble TPE-ssHPA-Ac@Au NCs composites without participation of any free organic compounds were constructed. • The ratiometric sensor showed reversible photoluminescence response to CO 2 /N 2 cycling. • The ratiometric sensor showed reversible emission color change to CO 2 /N 2 cycling. Nowadays, developing effective CO 2 detecting methodologies is of great significance. Herein, a hybrid ratiometric fluorescence sensor by decorating tetraphenylethene (TPE) and gold nanoclusters (Au NCs) into disulfide functionalized hyperbranched poly(amido amine) skeleton was designed for efficient and accurate ratiometric detection of dissolved CO 2 in the range of 3.8 × 10−4 – 1.9 × 10-2 mol·L-1 with a detection limit of 7.8 μ M. The emission ratio and color were reversible through switching the CO 2 /N 2 stimuli. Finally, this fluorescent probe was proven to be effective for determining the CO 2 concentration in real samples. This is the first report of water-soluble, quantitatively CO 2 -responsive, ratiometric fluorescence sensor synergizing TPE and Au NCs in the amino-rich hyperbranched skeleton without participation of any free organic compounds. [ABSTRACT FROM AUTHOR]

Aims: The blood‐brain barrier (BBB) is a specialized and indispensable structure in brain blood vessels that is damaged during Alzheimer's disease (AD). CD147 is expressed on the BBB and deeply engaged in the AD pathological process. In this study, we aimed to provide a better understanding of the roles of CD147 in BBB function in health and neurodegenerative disease. Methods and Results: We measured CD147 expression in mouse brains and demonstrated that CD147 is exclusively expressed in brain endothelial cells (BECs), and its expression decreases with age. After constructing endothelial‐specific CD147 knockout mice, we performed RNA‐sequencing on BECs isolated from mice of different ages as well as a range of database analyses. We found that endothelial CD147 is essential for the dual functions of the BBB, including barrier maintenance and transporter regulation. This study also shows that CD147 plays a pivotal role in neurodegenerative diseases, particularly in AD. Conclusions: Our findings suggested that targeting CD147 in BECs may represent a novel therapeutic strategy, which promoted the design of future experimental investigations and the mechanistic understanding of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

T cell acute lymphoblastic leukemia (T-ALL) is invasive and heterogeneous, and existing therapies are sometimes unsuccessful. Chimeric antigen receptor (CAR) T cell therapy is a breakthrough tumor treatment method, particularly for B cell acute lymphoblastic leukemia. We found that CD147 was highly expressed in tumor T cells of T-ALL patients and T cell lymphoma. Therefore, CD147-CAR T cells that contain a humanized single-chain variable fragment targeting human CD147 and a second-generation CAR frame were constructed for treating T-ALL. CD147-CAR T cells were able to maintain a healthy proliferation rate, preserving a subset of CD62L+/CCR7+ memory T cells. CD147-CAR T cells showed a potent anti-tumor activity against human T-ALL cell line and T-ALL blasts, releasing high level of cytokines in the process. However, CD147-CAR T cells exhibited potential safety toward human normal cells and CD147-deficent cells. NOD/ShiLtJGpt-Prkdcem26Cd52Il2rgem26Cd22/Gpt mice were used to establish a T-ALL xenograft model and CD147-CAR T cells conferred robust protection against T-ALL progression and significantly improved survival in mice. Overall, we found that CD147 is a potential antigen target of CAR T cell therapy for T-ALL. [ABSTRACT FROM AUTHOR]

In view of engineering application, it is practicable to decompose the aerodynamics into three components: the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration, the mathematical models of 6-component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynamics, respectively. The results show that: (1) unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; (2) unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability are analyzed by numerical simulation. [ABSTRACT FROM AUTHOR]