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Human papillomavirus (HPV) is the most common viral infection of the reproductive tract, which can increase the risk of cervical cancer. Development of HPV-specific vaccines that can be recognized and presented by human leukocyte antigen (HLA) system is considered as an important approach to prevention and treatment of cervical cancer. In this study, a combination of bioinformatics analysis and peptide binding assay was described to identify potential cytotoxic T lymphocyte epitopes from the HPV genome. In the procedure, a structure-based quantitative structure-activity relationship (SB-QSAR) was used to analyze the intermolecular interactions between HLA proteins and peptide epitopes, and the obtained nonbonded descriptors were then correlated linearly and nonlinearly with HLA-peptide affinities by using partial least squares regression and support vector machine, respectively. Several SB-QSAR models were established and evaluated rigorously, from which the best predictor was applied to virtual screening against thousands of nonapeptide segments generated from the HPV-16 genome. With this protocol a number of peptide ligands were inferred to have high affinity for a variety of frequently observed HLA-A alleles, including 0101, 0201, 0202, 0203, 0206 and 0301, from which several promising candidates were selected and tested in vitro to determine their binding strength toward HLA proteins. Consequently, several peptides were identified as potent HLA binders with half-maximal binding BL at micromolar level. The molecular mechanism underlying the high-affinity binding of identified peptide ligands to HLA proteins was also investigated in detail. [ABSTRACT FROM AUTHOR]

The solubilities of ternary system Na 2 SO 4 –CO(NH 2 ) 2 –H 2 O and MgSO 4 –CO(NH 2 ) 2 –H 2 O and quaternary system Na 2 SO 4 –MgSO 4 –CO(NH 2 ) 2 –H 2 O at 60 °C were measured by isothermal method, and the corresponding phase diagrams were studied. There are five crystalline fields in the quaternary system Na 2 SO 4 –MgSO 4 –CO(NH 2 ) 2 –H 2 O at 60 °C, which correspond to MgSO 4 ·6H 2 O, Na 2 SO 4 ·MgSO 4 ·4H 2 O, Na 2 SO 4 , CO(NH 2 ) 2 and MgSO 4 ·CO(NH 2 ) 2 ·4H 2 O respectively. On the basis of the analyses of the phase diagram of the quaternary system Na 2 SO 4 –MgSO 4 –CO(NH 2 ) 2 –H 2 O at 60 °C and 25 °C, Na 2 SO 4 and Mg–N compound fertilizers can be produced using CO(NH 2 ) 2 as salting-out agent directly. On the basis of the extended Pitzer model of electrolyte solution theory, the solubilities of Na 2 SO 4 –MgSO 4 –CO(NH 2 ) 2 –H 2 O system at 60 °C were calculated. The results showed that calculated values were well consistent with experimental results. [ABSTRACT FROM AUTHOR]

Introduction: Low Clostridium leptum levels are a risk factor for the development of asthma. C. leptum deficiency exacerbates asthma; however, the impact of early-life C. leptum exposure on cesarean-delivered mice remains unclear. This study is to determine the effects of early-life C. leptum exposure on asthma development in infant mice. Methods: We exposed infant mice to C. leptum (fed-CL) and then induced asthma using the allergen ovalbumin (OVA). Results: Fed-CL increased regulatory T (Treg) cells in cesarean-delivered mice compared with vaginally delivered mice. Compared with OVA-exposed mice, mice exposed to C. leptum + OVA did not develop the typical asthma phenotype, which includes airway hyper-responsiveness, cell infiltration, and T helper cell subset (Th1, Th2, Th9, Th17) inflammation. Early-life C. leptum exposure induced an immunosuppressive environment in the lung concurrent with increased Treg cells, resulting in the inhibition of Th1, Th2, Th9, and Th17 cell responses. Conclusion: These findings demonstrate a mechanism whereby C. leptum exposure modulates adaptive immunity and leads to failure to develop asthma upon OVA sensitization later in life. [ABSTRACT FROM AUTHOR]

Inspired by the synergistic effects of dietary natural products with different scaffolds on the inhibition of cancer cell proliferation, incorporation of central (1 E ,4 E )-1,4-penta-dien-3-one linker (an optimal substitute for the central metabolically unstable diketone linker of curcumin), 1-alkyl-1 H -imidazol-2-yl (a promising bioisostere of terminal aryl group in curcumin), and chromone (the common pharmacophore in genistein and quercetin) into one chemical entity resulted in ten new hybrid molecules, 3-((1 E ,4 E )-5-(1-alkyl-1 H -imidazol-2-yl)-3-oxopenta-1,4-dien-1-yl)-4 H -chromen-4-ones. They were synthesized through a three-step transformation using acid-catalyzed aldol condensation as key step. The WST-1 cell proliferation assay showed that they have greater anti-proliferative potency than curcumin, quercetin, and genistein on both androgen-dependent and androgen-independent human prostate cancer cells. [ABSTRACT FROM AUTHOR]

BCR-ABL tyrosine kinase inhibitor imatinib fails to eradicate leukemia stem cells (LSCs), the underlying mechanisms maintaining CML LSCs remain poorly understood. Here, we showed that transient inhibition of miR-21 by antagomiR-21 markedly increased imatinib-induced apoptosis in CML, but not normal CD34 + stem/progenitor cells. Furthermore, PI3K inhibitors also significantly sensitized CML CD34 + cells to imatinib-induced apoptosis. MiR-21 or PI3K inhibitor in combination with imatinib treatment significantly decreased AKT phosphorylation and c-Myc expression than either agent did alone, but did not affect Bim and Bcl-6 expresssion. These findings indicate that miR-21 is required for maintaining the imatinib-resistant phenotype of CML CD34 + cells through PI3K/AKT signaling pathway, thus providing the basis for a promising therapeutic approach to eliminate CML LSCs. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large‐scale production. Herein, we report the synthesis of imine and aminal‐linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta‐diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub‐kilogram quantities at a relatively low cost. Proof‐of‐concept studies demonstrate that the POPs can be used as high‐performance sorbents for CO2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost‐effective approach for large‐scale synthesis of various POPs. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large‐scale production. Herein, we report the synthesis of imine and aminal‐linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta‐diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub‐kilogram quantities at a relatively low cost. Proof‐of‐concept studies demonstrate that the POPs can be used as high‐performance sorbents for CO2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost‐effective approach for large‐scale synthesis of various POPs. [ABSTRACT FROM AUTHOR]

Pore size plays a critical role in determining the performance of metal‐organic frameworks (MOFs) in catalysis, sensing, and gas storage or separation. However, revealing the pore‐size/property relationship remains extremely challenging because ideal structure models possessing different pore sizes but having the same components are lacking. In this work, a solvent‐coordination directed structure swelling method was developed for modulating the ratio between the large and narrow pore phases of a flexible MOF, MIL‐88B. Pore‐size‐dependent gas sensitivity and selectivity were studied for the first time in the MIL‐88B samples. The optimized MIL‐88B‐20 % sample showed one of the best sensing performances among all the reported MOF‐based H2S‐sensing materials. This work not only provides a method to synthesize ideal structure models for revealing the relationship between pore‐size and properties, but also may inspire the development of high‐performance gas sensing materials. [ABSTRACT FROM AUTHOR]

Pore size plays a critical role in determining the performance of metal‐organic frameworks (MOFs) in catalysis, sensing, and gas storage or separation. However, revealing the pore‐size/property relationship remains extremely challenging because ideal structure models possessing different pore sizes but having the same components are lacking. In this work, a solvent‐coordination directed structure swelling method was developed for modulating the ratio between the large and narrow pore phases of a flexible MOF, MIL‐88B. Pore‐size‐dependent gas sensitivity and selectivity were studied for the first time in the MIL‐88B samples. The optimized MIL‐88B‐20 % sample showed one of the best sensing performances among all the reported MOF‐based H2S‐sensing materials. This work not only provides a method to synthesize ideal structure models for revealing the relationship between pore‐size and properties, but also may inspire the development of high‐performance gas sensing materials. [ABSTRACT FROM AUTHOR]

Designing porous materials for C2H2 purification and safe storage is essential research for industrial utilization. We emphatically regulate the metal‐alkyne interaction of PdII and PtII on C2H2 sorption and C2H2/CO2 separation in two isostructural NbO metal–organic frameworks (MOFs), Pd/Cu‐PDA and Pt/Cu‐PDA. The experimental investigations and systematic theoretical calculations reveal that PdII in Pd/Cu‐PDA undergoes spontaneous chemical reaction with C2H2, leading to irreversible structural collapse and loss of C2H2/CO2 sorption and separation. Contrarily, PtII in Pt/Cu‐PDA shows strong di‐σ bond interaction with C2H2 to form specific π‐complexation, contributing to high C2H2 capture (28.7 cm3 g−1 at 0.01 bar and 153 cm3 g−1 at 1 bar). The reusable Pt/Cu‐PDA efficiently separates C2H2 from C2H2/CO2 mixtures with satisfying selectivity and C2H2 capacity (37 min g−1). This research provides valuable insight into designing high‐performance MOFs for gas sorption and separation. [ABSTRACT FROM AUTHOR]

Designing porous materials for C2H2 purification and safe storage is essential research for industrial utilization. We emphatically regulate the metal‐alkyne interaction of PdII and PtII on C2H2 sorption and C2H2/CO2 separation in two isostructural NbO metal–organic frameworks (MOFs), Pd/Cu‐PDA and Pt/Cu‐PDA. The experimental investigations and systematic theoretical calculations reveal that PdII in Pd/Cu‐PDA undergoes spontaneous chemical reaction with C2H2, leading to irreversible structural collapse and loss of C2H2/CO2 sorption and separation. Contrarily, PtII in Pt/Cu‐PDA shows strong di‐σ bond interaction with C2H2 to form specific π‐complexation, contributing to high C2H2 capture (28.7 cm3 g−1 at 0.01 bar and 153 cm3 g−1 at 1 bar). The reusable Pt/Cu‐PDA efficiently separates C2H2 from C2H2/CO2 mixtures with satisfying selectivity and C2H2 capacity (37 min g−1). This research provides valuable insight into designing high‐performance MOFs for gas sorption and separation. [ABSTRACT FROM AUTHOR]

Development of a flexible low-cost robotic system to grasp various 3D workpieces is of practical important. Traditional approaches on 3D grasping usually need to compute the effective contact positions based on sufficient conditions, such as “force-closure” or “form-closure,” to prevent all the motions of the grasped objects. Compared with the previous work motivated by high-precision applications, caging provides a way to manipulate an object without needing to immobilize it. However, most caging conditions consider only 2D motions of the object in grasping. In some cases, other motions in 3D space, e.g., the pitch and roll rotations of the objects, would also possibly change a caging configuration to an uncaging configuration. This paper aims to discuss caging with frictionless contact, by taking into consideration of all the motions of the object. We first discuss the relationship between the gripper configuration and the state of the grasped object in grasping, where all the motions of the object are taken into account. We then establish the sufficient conditions to find a set of 3D caging configurations in terms of the width of the object's projection and the gap of the gripper, such that we can utilize the projection to find the feasible placements of the pins to determine the caging configuration. Furthermore, we discuss how to find the caging configuration that is capable of leading to a form-closure based on attractive region formed in the configuration space. [ABSTRACT FROM PUBLISHER]

The major challenge for image denoising is how to effectively remove the noise and preserve the detail information to get better visual quality and higher peak signal-to-noise ratio (PSNR). A new image denoising methods based on combination of multivariate shrinkage model in shiftable complex directional pyramid (PDTDFB) domain and principal neighborhood dictionary (PND) non-local means algorithm in spatial domain is proposed. In PDTDFB domain, the PDTDFB coefficients are modeled as multivariate non-Gaussian distribution taking into account the interscale and intrascale dependency correlation. Then a multivariate shrinkage function is derived by the maximum a posterior (MAP) estimator and the denoised coefficients are obtained. Although the PDTDFB-based algorithm achieves efficient denoising result, it is prone to producing salient artifacts which relate to the structure of the PDTDFB. Principal neighborhood dictionary (PND) is further employed to alleviate the artifacts with small computational load in spatial domain. Experimental results indicate that the proposed method is competitive with other excellent denoising methods in terms of PSNR value and visual quality. [ABSTRACT FROM AUTHOR]

We investigate the analytical performance of label free porous silicon Bloch surface wave (BSW) devices as protease sensors. Protease detection is based on the digestion of gelatin, which was covalently immobilized onto the surface modified PSi structure. Exposure to the protease enzyme, subtilisin initiates catalytic degradation of the gelatin gel network. The degradation of this network which is present in the top layer of the sensor, causes a blue shift in the spectral position of the Bloch surface mode. The magnitude of the resonance shift is directly proportional to the concentration of subtilisin and the digestion time. The lowest concentration of subtilisin detected was 370 pM. Secondary spectral features, such as band-edge modes, are relatively insensitive to refractive index changes in the superficial layers and thus can be utilised as an internal reference to exclude any nonspecific adsorption and bonding that may occur through the bulk of the film. The advantages of the system here include fast diffusion of digested product and self-referencing capability. [ABSTRACT FROM AUTHOR]

Graph matching is a fundamental problem in pattern recognition and computer vision. In this paper we introduce a novel graph matching algorithm to find the specified number of best vertex assignments between two labeled weighted graphs. The problem is first explicitly formulated as the minimization of a quadratic objective function and then solved by an optimization algorithm based on the recently proposed graduated nonconvexity and concavity procedure (GNCCP). Simulations on both synthetic data and real world images witness the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: Caring for dying patients is stressful but an unavoidable responsibility of nurses. However, little is known about Chinese oncology nurses' experience of caring for dying cancer patients who are in their final days. Purpose: To elucidate Chinese oncology nurses' experience of caring for dying cancer patients. Methods: This is a qualitative descriptive study, semi-structured interviews was utilized to explore views of purposive sample of 28 nurses who have been taking care of terminally ill patients in a cancer hospital in Tianjin, mainland China. Transcripts were entered into NVivo. Qualitative thematic analysis was used to analyze the data for significant statements and phrases that in turn were organized into themes and sub-themes. Results: Five themes were identified in the data: end-of-life care for dying cancer patients, end-of-life care for family members, cultural sensitivity and communication, moral distress and self-limitations, self-reflection and benefit-finding. Death is a taboo in traditional Chinese culture. This increases the difficulty of effective communication between nurses, patients and families. Although nurses suffered emotional distress when caring for dying cancer patients, these experiences helped them to reflect on the meaning of death and life, and positively influenced their daily lives, attitudes and behaviors toward caring for the dying. Chinese nurses had strong willingness to offer quality end-of-life care to patients and families, however, they suffered moral distress because of self-limitation, lack of knowledge and confidence and inexperience in psychological care. Conclusions: End-of-life care in China reflects and has been influenced by the traditional Chinese culture. Chinese nurses reported suffering but also benefiting from their experiences. End-of-life cancer care training is needed by Chinese oncology nurses, especially for those who are younger and less experienced. [ABSTRACT FROM AUTHOR]

Feature correspondence lays the foundation for many tasks in computer vision and pattern recognition. In this paper the directed structural model is utilized to represent the feature set, and the correspondence problem is then formulated as the structural model matching. Compared with the undirected structural model, the proposed directed model provides more discriminating ability and invariance against rotation and scale transformations. Finally, the recently proposed convex–concave relaxation procedure (CCRP) is generalized to approximately solve the problem. Extensive experiments on synthetic and real data witness the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Tumor-infiltrating lymphocytes may be a manifestation of antitumor immunity. In the present study, hepatocellular carcinoma (HCC) and pericancerous non-tumor liver tissues samples were obtained from 86 surgical patients who had not received preoperative treatment. The cellular expression levels of CD4 and CD8 were immunohistochemically examined in the two tissue groups using tissue microarrays, to evaluate their clinicopathological relevance. Immunohistochemically, CD4 and CD8 T cells were observed in the tumor parenchyma and tumor stroma, and the intensity of CD4 and CD8 immunoreactivity w as h omogeneous i n a ll H CC s amples examined. Morphometrically, the average numbers of CD4- and CD8-positive T cells were significantly increased in the tumor stroma, compared with those in the tumor parenchyma (tumor stroma versus tumor parenchyma: 22±3.6 versus 7.4±0.9 in CD4, 32.8±4.2 versus 16±2.5 in CD8; both P<0.01). Furthermore, the average numbers of CD8-positive T cells in the tumor parenchyma and stroma were significantly increased, compared with the average numbers of CD4-positive cells (P<0.05). In addition, in the tumor parenchyma and stroma, the average numbers of CD8 T cells were significantly higher in patients with tumor diameters ≤5 cm compared with those in patients with tumor diameters >5 cm (diameter ≤5 cm versus diameter >5 cm: 18.1±3.3 versus 12.2±3.8 in tumor parenchyma, 36.5±4.8 versus 21.9±8.9 in tumor stroma; both P<0.05). In addition, CD8 expression was significantly enhanced in patients with chronic hepatitis and cirrhosis, compared with paired tumor parenchymal tissues (P<0.01). Furthermore, a significant positive correlation was observed between CD4 and CD8 expression in the tumor parenchyma and stroma (both P<0.001). These observations suggest that tumor parenchyma- or stroma-infiltrating CD8 T cells may be involved in HCC tumor diameter control. [ABSTRACT FROM AUTHOR]

The convex and concave relaxation procedure (CCRP) was recently proposed and exhibited state-of-the-art performance on the graph matching problem. However, CCRP involves explicitly both convex and concave relaxations which typically are difficult to find, and thus greatly limit its practical applications. In this paper we propose a simplified CCRP scheme, which can be proved to realize exactly CCRP, but with a much simpler formulation without needing the concave relaxation in an explicit way, thus significantly simplifying the process of developing CCRP algorithms. The simplified CCRP can be generally applied to any optimizations over the partial permutation matrix, as long as the convex relaxation can be found. Based on two convex relaxations, we obtain two graph matching algorithms defined on adjacency matrix and affinity matrix, respectively. Extensive experimental results witness the simplicity as well as state-of-the-art performance of the two simplified CCRP graph matching algorithms. [ABSTRACT FROM AUTHOR]

Covering: through January 2014 Zampanolide is a marine natural macrolide and a recent addition to the family of microtubule-stabilizing cytotoxic agents. Zampanolide exhibits unique effects on tubulin assembly and is more potent than paclitaxel against several multi-drug resistant cancer cell lines. A high-resolution crystal structure of αβ-tubulin in complex with zampanolide explains how taxane-site microtubule-stabilizing agents promote microtubule assemble and stability. This review provides an overview of current developments of zampanolide and its related but less potent analogue dactylolide, covering their natural sources and isolation, structure and conformation, cytotoxic potential, structure–activity studies, mechanism of action, and syntheses. [ABSTRACT FROM AUTHOR]

The synergistic effect of rigid organic framework and soft lattice makes metal‐organic framework (MOF) luminescent materials more widely used. Herein, 2D lead‐MOFs are reported that produce white light through the coregulation of free excitons and self‐trapped excitons. The synthesized BIF‐142‐Cl shows outstanding white‐light emission with the CIE color coordinates of (0.312, 0.335) close to pure white light, the excellent color rendering index (CRI) of 90.4, and the gentle correlation color temperature (CCT) of 5364 K. Meanwhile, the multicolor emission from blue to white light can be adjusted by changing the excitation wavelength. Furthermore, photophysical studies confirm that the strong electronic phonon coupling in the excited state of lead halide polyhedrons is directly responsible for the generation of self‐trapped excitons. This synthetic strategy of introducing tunable dual emission centers not only offers a prospect for the development of solid‐state lighting materials but also widens the path to the fields of anticounterfeiting, display media, and information identification. [ABSTRACT FROM AUTHOR]

It is recognized that dimensions have a decisive influence on the properties of materials. Metal–organic frameworks as third-order nonlinear optical (NLO) materials have attracted much attention recently. However, research on the influence of dimensions on third-order NLO properties of MOFs has not been reported. In this work, we synthesized two porphyrin MOFs (PMOFs) constructed with π-conjugated tetracarboxyphenylporphyrin (TCPP) and in situ formed 1,2-bis(1H-benzo[d]imidazol-2-yl)ethene (BIE) conjugated ligands. In both PMOFs, Zn2(CO2)4 paddlewheel units are connected by TCPP-Zn ligands to form a 2D layer. Interestingly, these layers are linked by BIE ligands to form a bilayer in PMOF-1 and a 3D pillar-layered framework in PMOF-2, which serve as structural models to evaluate the influence of dimensions on third-order NLO properties. It is speculated that the 3D pillar-layered framework in PMOF-2 with BIE conjugated pillars is more conducive to interlayer charge transfer than the two-dimensional bilayer in PMOF-1, thus achieving a better third-order NLO performance. The third-order NLO test results of PMOFs in a polydimethylsiloxane (PDMS) matrix showed that PMOF-2 displayed a higher nonlinear absorption coefficient, large third-order susceptibility and lower limiting threshold than PMOF-1/PDMS, which may be mainly attributed to the fact that the 3D pillar-layered framework is more conducive to interlayer charge transfer than the two-dimensional bilayer. This work reveals the influence of dimensions on third-order nonlinear properties which will help to explore new MOF materials with excellent third-order NLO properties. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we propose a concavely regularized convex relaxation based graph matching algorithm. The graph matching problem is firstly formulated as a constrained convex quadratic program by relaxing the feasible set from the permutation matrices to doubly stochastic matrices. To gradually push the doubly stochastic matrix back to be a permutation one, an objective function is constructed by adding a simple weighted concave regularization to the convex relaxation. By gradually increasing the weight of the concave term, minimization of the objective function will gradually push the doubly stochastic matrix back to be a permutation one. A concave–convex procedure (CCCP) together with the Frank–Wolfe algorithm is adopted to minimize the objective function. The algorithm can be used on any types of graphs and exhibits a comparable performance as the PATH following algorithm, a state-of-the-art graph matching algorithm but applicable only on undirected graphs. [Copyright &y& Elsevier]

Abstract: A computational model of visual cortex has raised great interest in developing algorithms mimicking human visual systems. The max-operation is employed in the model to emulate the scale and position invariant responses of the visual cells. We further extend this idea to enhance the tolerance of visual classification against the general intra-class variability. A general architecture of the basic block constituting the model is first presented. The architecture adaptively chooses the best matching template from a set of competing templates to predict the label of the incoming sample. To optimize the non-convex and non-smooth objective function resulted, we develop an algorithm to train each template alternately. Experiments show that the proposed method significantly outperforms linear classifiers as a template matching method in several image classification tasks, and is much more computationally efficient than other commonly used non-linear classifiers. In the image classification task on the Caltech 101 database, the performance of the biologically inspired model is obviously boosted by incorporating the proposed method. [Copyright &y& Elsevier]

In this paper we propose the graduated nonconvexity and concavity procedure (GNCCP) as a general optimization framework to approximately solve the combinatorial optimization problems defined on the set of partial permutation matrices. GNCCP comprises two sub-procedures, graduated nonconvexity which realizes a convex relaxation and graduated concavity which realizes a concave relaxation. It is proved that GNCCP realizes exactly a type of convex-concave relaxation procedure (CCRP), but with a much simpler formulation without needing convex or concave relaxation in an explicit way. Actually, GNCCP involves only the gradient of the objective function and is therefore very easy to use in practical applications. Two typical related NP-hard problems, partial graph matching and quadratic assignment problem (QAP), are employed to demonstrate its simplicity and state-of-the-art performance. [ABSTRACT FROM PUBLISHER]

Two coordination polymers, [Co2(Hcpip)2(phth)] n ·3 n(H2O) ( 1) and [Mn2(Hcpip)2(phth)] n ( 2), {H2cpip = 2-(2-carboxyphenyl)imidazo[4,5-f](1,10)- phenanthroline, H2phth = phthalic acid}, were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Complex 1 is a 1D chain, in which the dinuclear [Co2(Hcpip)2]2+ units are linked through (phth)2- anions. Complex 2 is a 2D layer structure, which is constructed from the 1D chains bridged by (phth)2- anions. The magnetic properties of 1 and 2 show that the weak ferromagnetic interactions occurred between CoII ions in 1 and a weak antiferromagnetic interactions exist between MnII ions in 2. These two complexes have good thermal stabilities. [ABSTRACT FROM AUTHOR]

Abstract: Exploiting both appearance similarity and geometric consistency is popular in addressing the feature correspondence problem. However, when there exist outliers the performance generally deteriorates greatly. In this paper, we propose a novel partial correspondence method to tackle the problem with outliers. Specifically, a novel pairwise term together with a neighborhood system is proposed, which, together with the other two pairwise terms and a unary term, formulates the correspondence to be solved as a subgraph matching problem. The problem is then approximated by the recently proposed Graduated Non-Convexity and Graduated Concavity Procedure (GNCGCP). The proposed algorithm obtains a state-of-the-art accuracy in the existence of outliers while keeping computational complexity and storage complexity. Simulations on both the synthetic and real-world images witness the effectiveness of the proposed method. [Copyright &y& Elsevier]

Highlights: [•] Four new coordination polymers based on 2-(2-carboxyphenyl)imidazo(4,5-f) 1,10-phenanthroline were constructed. [•] Different auxiliary ligands play an important role for the construction of complexes 2–4. [•] The coordination geometry of Pb(II) ion in 1–4 is investigated. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to compare magnesium-substituted and pure hydroxyapatite coatings on the promotion of osteogenesis in vitro and on the osseointegration in vivo. Methods Electrochemically deposited pure hydroxyapatite ( EDHA) or electrochemically deposited magnesium-substituted hydroxyapatite ( EDMHA) coatings were formed on the surface of pure titanium disks or implants. MC3T3-E1 preosteoblasts were cultured in the EDHA and EDMHA coated disks, and cell growth, alkaline phosphatase ( ALP) activity, and osteocalcin secretion were measured at various time points. For studies on osseointegration, 30 roughened implants coated either with EDHA or EDMHA ( n = 15 for each coating) were implanted in the femurs of 15 NZW rabbits. After 2, 4, and 8 weeks, femurs were retrieved and prepared for histomorphometric evaluation ( n = 5 for each coating at each time point). Results MC3T3-E1 cells cultured on EDMHA coated disks showed increased cell number, ALP, and osteocalcin secretion compared with the EDHA coated disks at all time points ( P < 0.05 for all). Histologic observation of the coated implants showed woven bone in direct contact with both implant surfaces after 2 weeks and mature bone after 8 weeks. While there were no differences in the amount of bone between the threads at any time point, the percentage of implant in direct contact with bone (bone implant contact) was slightly higher along the EDMHA coated implants at 2 weeks ( P = 0.086), although this difference was no longer seen at 4 and 8 weeks. Conclusion Mg-substituted HA coated surfaces promote osteogenic differentiation of preosteoblasts in vitro and may improve implant osseointegration during the early stages of bone healing compared with pure EDHA coated surfaces. [ABSTRACT FROM AUTHOR]

Mild cognitive impairment affects 36% of people aged ≥65 years in China, around 50% of whom will develop dementia within 3 years. Early intervention can slow disease progression and delay the onset of dementia; however, whether a multicomponent intervention can decelerate the progression of mild cognitive impairment remains unknown. To evaluate the effects of a multicomponent intervention to slow mild cognitive impairment progression in Chinese patients. Randomized controlled trial. This study was conducted in two large regional communities in Guangzhou, China. Patients aged ≥ 65 years diagnosed with mild cognitive impairment were included. A total of 112 eligible participants were assigned to receive either a 6-month multicomponent intervention or usual care from September 2019 until January 2021. Data were collected at the beginning of the study and at 1, 3, and 6 months thereafter. The primary outcomes were cognitive function, comprehensive physical capacity, depression, and quality of life. Analysis followed the intention-to-treat principle. A generalized estimating equation was used to determine intervention effects. At baseline, clinical characteristics did not differ significantly between groups. Significant interaction effects between time and group were detected (p < 0.001), indicating that the scores of five outcomes (cognitive function, short physical performance battery, timed up and go test, quality of life, and depression) of intervention and control groups changed differently over time. Participants in the intervention group were found to have a significantly greater improvement in cognitive function, physical function, quality of life, and fewer depression symptoms compared with the control group at baseline and follow-up periods. This study demonstrates the beneficial effects of a multicomponent intervention on cognitive function, physical function, depression symptoms, and quality of life in people with mild cognitive impairment in the East Asia region. The effectiveness and feasibility of this intervention program suggest that its application should be promoted in community settings to delay the progression of disease in people with mild cognitive impairment. Registration number: ChiCTR1900026042 Tweetable abstract: The multicomponent intervention improves cognitive/physical function, depression, and quality of life, slowing cognitive impairment progression. [ABSTRACT FROM AUTHOR]

Objectives: Evaluate hBMP-2 expression following gene delivery from plasmid multilayers formed on sandblasted titanium in vitro and bone formation around similarly prepared implant surfaces in vivo. Materials and methods: Multilayers of cationic lipid/rhBMP-2 plasmid DNA complex (LDc) and anionic hyaluronic acid (HA) was assembled on sandblasted-dual acid etched pure titanium disks or implant surfaces using layer-by-layer (LBL) assembly. Gene delivery and hBMP-2 expression in cells exposed to the LDc multilayers was measured in vitro. To determine the effect of BMP delivery from such multilyaers in vivo, roughened implants coated with BMP-2 LDc multilayers or uncoated control implants (n = 15 for both) were implanted in the femurs of NZW rabbits. After 2, 4, 8 weeks, femurs were retrieved and prepared for histomorphometric evaluation (n = 5 rabbits per time point). Results: MC3T3-E1 cells cultured directly on the BMP-2 LDc coated titanium disks showed EGFP and hBMP-2 expression after 48 h in culture. Increased gene delivery occurred by increasing the number of assembly layers when cells were cultured for 48 h. Cells cultured on LDc coated surfaces had significantly higher cell viability than control cells cultured on uncoated porous titanium surfaces. Histologic observation of the implants showed that after 4 weeks healing, the bone to implant contact (BIC) on the LDc coated surface was much lower than that on the control surface, but didn't reach significant. In contrast, the percentage of bone within the implant's threads was significantly higher than the control group (P = 0.047). Conclusion: The BMP-2 gene coated sandblasted dual acid etched titanium implants slightly accelerated early bone formation around implants. [ABSTRACT FROM AUTHOR]

The reaction microscopic mechanism of mixed aqueous solutions of nitrobenzene and hydrogen peroxide under different conditions was studied by the laser flash photolysis technique (266 nm). The main characteristic peaks in these transient absorption spectra were attributed and the build-up/decay trends of several transient species were investigated. The transient absorption peaks of 285 nm and 305 nm were attributed to when nitrobenzene aqueous solutions were irradiated by 266 nm UV light and the decay rate constant was k 285 nm = 1.22 × 104 s−1 and k 305 nm = 1.05 × 104 s−1 in the presence of N2. k 285 nm and k 305 nm increased to 1.32 × 104 s−1 and 2.05 × 104 s−1, respectively, in the presence of O2. OH radical can be produced through the 266 nm laser flash photolysis of hydrogen peroxide in aqueous solutions. The rate constant of the reaction between OH radical and nitrobenzene was measured to be (3.6–6.0) × 109 (L · mol−1 · s−1). The intermediate of the C6H5NO2-OH adduct can undergo secondary self-decay with a reaction rate of 2k/ϵl = 1.82 × 106 s−1. The C6H5NO2-OH adduct is able to react with O2 to form C6H5NO2-OHO2 with a rate constant of (6.6 ± 0.56) × 107 (L · mol−1 · s−1). [ABSTRACT FROM PUBLISHER]

Ethy|ene gas is essential for many developmental processes and stress responses in plants. ETHYLENE INSENSITIVE2 (EIN2), an NRAMP-like integral membrane protein, prays an essential role in ethylene signaling, but its function remains enigmatic. Here we report that phosphorylation-regulated proteolytic processing of EIN2 triggers its endoplasmic reticulum (ER)--to--nucleus translocation. ER-tethered EIN2 shows CONSTITUTIVE TRIPLE RESPONSE1 (CTR1) kinase--dependent phosphorylation. Ethylene triggers dephosphorylation at several sites and proteolytic cleavage at one of these sites, resulting in nuclear translocation of a carboxyl-terminal EIN2 fragment (EIN2-C'). Mutations that mimic EIN2 dephosphorylation, or inactivate CTR1, show constitutive cleavage and nut|ear localization of EIN2-C' and EIN3 and EIN3-LIKE1--dependent activation of ethylene responses. These findings uncover a mechanism of subcellular communication whereby ethylene stimulates phosphorylation-dependent cleavage and nuclear movement of the EIN2-C' peptide, linking hormone perception and signaling components in the ER with nuclear-localized transcriptional regulators. [ABSTRACT FROM AUTHOR]

This article investigates the event and self‐triggered adaptive output feedback control of a manipulator suffering from limited knowledge of states and dynamics, to realize the trajectory tracking with less communication occupation. In this control scheme, the configuration of co‐located observer and controller with discontinued output feedback is considered. To guarantee the convergence of observation and control errors with few events as much as possible, an adaptive event‐triggered mechanism based on model estimation is constructed to compensate for the error accumulation produced by the intermittent open‐loop. Based on the model state, adaptive backstepping method with network estimation is used for deriving the controller, to solve the control stability under uncertainty of system dynamics. Aiming at removing the "derivative explosion and singularity" of discontinuous virtual signal, a first‐order filter is incorporated to get the smooth approximation of the virtual signal, and an additional self‐adaption signal is designed for the filtering error compensation. In view of the state updating at event instants, a gradual updating method is designed such that the state jumping‐induced chattering instability could be handled. With the above designed method, a dead‐zone event‐triggered condition with the relative threshold and variable tolerance boundary is built to avoid Zeno‐behavior. Furthermore, an easy‐implemented self‐triggered mechanism is also constructed. Finally, the Lyapunov function is utilized to derive the setting principle for the stability of the system, and the simulation is given to show the validity of the proposed control method. [ABSTRACT FROM AUTHOR]

Sensorless manipulation strategies have been successfully used in the precision robotic assembly. Most previous work in this area has concentrated on inserting a peg into a fixed hole. However, in some cases, e.g., the assembly of piston-peg-rod of the automotive engine, due to the motion of piston, the position of the hole in piston is hard to be fully constrained. The purpose of this paper is to give a novel sensorless manipulation strategy for the high-precision assembly of a peg into an unfixed hole. Firstly, a decomposition method of the high-dimensional configuration space of the peg hole is analyzed. Subsequently, the robotic manipulations are proposed in the two low-dimensional spaces decomposed from the high-dimensional configuration space. Then, the attractive regions formed in the two sub-spaces are constructed, thus, the position and orientation uncertainties of the peg hole can be eliminated by the attractive regions and the robotic manipulations. Finally, a typical industry application, fitting a peg into an unfixed piston rod hole of the automotive engine, is used to validate the presented strategy. [ABSTRACT FROM AUTHOR]

Abstract: Variants in the gene encoding transcription factor 7-like 2 (TCF7L2) are associated with type 2 diabetes mellitus (T2D) in several ethnic groups. Two intronic variants, rs290487 and rs11196218, were originally identified as T2D modifiers in Hong Kong Chinese and Taiwan Chinese populations, respectively. However, discrepancies were noted in subsequent replicated studies. In this study, an association of these two loci with T2D was investigated in a Harbin Chinese population. Whereas the two populations in the initial studies were southern Han Chinese, Harbin Chinese are from northeastern China. The SNPs rs290487 and rs11196218 were genotyped by ligase detection reactions in 700 T2D patients and 570 unrelated non-diabetic controls. Association analyses, which were carried out using the case-control sample set, yielded a significant association between rs290487 and T2D, with a trend opposite to that described in a previous report. Specifically, rs290487T was found to be significantly associated with disease susceptibility (p =0.039), and the allelic OR of rs290487T carriers was 1.184 (95% CI 1.008–1.391). There was no significant association between rs11196218 and T2D. Taken together, TCF7L2 may be an important susceptibility gene for T2D in some Chinese populations. The discrepancies in the allelic associations determined for northern vs. southern Chinese allude to the presence of genetic variation among the Han Chinese. [Copyright &y& Elsevier]

In general, localization is a very important step in the manufacturing process, which can be considered as a prior process of assembly, machining, transportation, etc. Localization can be achieved with or without sensors. Compared with localization with sensors, localization without sensors can be more reliable, cheaper, and can have lower requirements on the environment. For example, localization without sensors can be achieved in a dark environment. However, it is more restrictive to the condition of the system. Localization of 2-D objects without sensors has been deeply investigated. Some theoretical results on 3-D-object localization without sensors have been given. On the other hand, some work has been carried out that tries to find methods to reduce uncertainties in the 3-D orientation of a polyhedron (i.e., the orientation of the polyhedron in a 3-D space). However, to the best of our knowledge, no practical and effective methods have been proposed, so far, to localize a polyhedron from any initial 3-D orientation to a unique 3-D orientation without sensors. This paper aims to find conditions and strategies for 3-D objects to be rotated from an unknown initial stable state to a unique stable state without sensors. The main contributions of this paper are given as follows: 1) It is discovered and proved that there are two classes of 3-D objects that can be rotated into a unique state from an arbitrary initial state without sensory feedback. 2) For these two classes of objects, the practical strategies are presented, and one example for each class is given to show the validity of the strategy. 3) Based on the above results, the robotic system and localization operations are illustrated, and some experimental results are given. [ABSTRACT FROM PUBLISHER]

Four novel taxoid analogs were conversionally synthesized from the C19-diterpenoid alkaloid deltaline, and their cytotoxic activities were evaluated against a small panel of cancer cell lines. [ABSTRACT FROM AUTHOR]

The regioselective demethylations of two C19-diterpenoid alkaloids, 2 and 3, have been achieved with HBr-HOAc, trimethylsilyl iodide, or BBr3. It was observed that HBr-HOAc is an optimal demethylating agent for these two C19-diterpenoid alkaloids because it could provide different O-demethylation products by using different reaction temperature and reaction time. Especially, 1-O-methyl group in 2 and 3, one of the most difficult ones to be demethylated, could be removed by the treatment with HBr-HOAc at an elevated temperature and a prolonged reaction time. [ABSTRACT FROM AUTHOR]

Abstract: An AE azabicyclic fragment, with a β-hydroxyl group at C-5 and a substituent at C-1, of the C19-diterpenoid alkaloids, was synthesized. The key reactions include an intramolecular Claisen-type condensation, double Mannich reaction, and stereoselective nucleophilic addition of carbonyl group with the assistance of steric effect of 1β-substituent. [Copyright &y& Elsevier]

Three new C-diterpenoid alkaloids, along with twenty-two known alkaloids, were isolated from the whole herbs of Delphinium tatsienense. The new alkaloids include a vakognavine-type C-diterpenoid alkaloid, designated as tatsienenseine A (), and two hetisine-type C-diterpenoid alkaloids, designated as tatsienenseines B () and C (). Their structures were elucidated by IR, HR-ESI-MS, 1D- and 2D-NMR analyses. [ABSTRACT FROM AUTHOR]

Manifold learning is a fast growing area of research recently. The main purpose of manifold learning is to search for intrinsic variables underlying high-dimensional inputs which lie on or are close to a low-dimensional manifold. Different from current theoretical works and applications of manifold learning approaches, in our work manifold learning framework is transferred to tracking feature extraction for the first time. The contributions of this article include three aspects. Firstly, in this article, we focus on tracking feature extraction for dynamic visual tracking on dynamic systems. The feature extracted in this article is based on manifold learning framework and is particular for dynamic tracking purpose. It can be directly applied to system control of dynamic systems. This is different from most traditional tracking features which are used for recognition and detection. Secondly, the proposed tracking feature extraction method has been successfully applied to three different dynamic systems: dynamic robot system, intelligent vehicle system and aircraft visual navigation system. Thirdly, experimental results have proven the validity of the tracking method based on manifold learning framework. Particularly, in the tracking experiments the vision system is dynamic. The tracking method is also compared with the well-known mean-shift tracking method, and tracking results have shown that our method outperforms the latter. [ABSTRACT FROM AUTHOR]

Three new diterpenoid alkaloids, along with eleven known alkaloids, were isolated from the whole herbs of Delphinium yunnanense. The new alkaloids include a rearranged-type C-diterpenoid alkaloid, named yunnanenseine A (), and two hetisine-type C-diterpenoid alkaloids, named yunnanenseine B and C ( and , resp.). Their structures were elucidated by detailed NMR-spectroscopic studies. [ABSTRACT FROM AUTHOR]

Several adaptive visual tracking algorithms have been recently proposed to capture the varying appearance of target. However, adaptability may also result in the problem of gradual drift, especially when the target appearance changes drastically. This paper gives some theoretical principles for online learning of target model, and then presents a novel adaptive tracking algorithm which is able to effectively cope with drastic variations in target appearance and resist gradual drift. Once target is localized in each frame, the patches sampled from target observation are first classified into foreground and background using an effective classifier. Then the adaptive, pure and time-continuous target model is extracted online through two processes: absorption process and rejection process, through which only the reliable features with high separability are absorbed in the new target model, while the “dangerous” features which may cause interfusion of background patterns are rejected. To minimize the influence of background and keep the temporal continuity of target model, two collaborative models dominant model and continuous model are designed. The proposed learning and generation mechanisms of target model are finally embedded in an adaptive tracking system. Experimental results demonstrate the robust performance of the proposed algorithm under challenging conditions. [ABSTRACT FROM AUTHOR]

Abstract: Principal component analysis (PCA) is widely used in recently proposed manifold learning algorithms to provide approximate local tangent spaces. However, such approximations provided by PCA may be inaccurate when local neighborhoods of the data manifold do not lie in or close to a linear subspace. Furthermore, the approximated tangent spaces can not fit the change in data distribution density. In this paper, a new method is proposed for providing faithful approximations to the local tangent spaces of a data manifold, which is proved to be more accurate than PCA. With this new method, an improved local tangent space alignment (ILTSA) algorithm is developed, which can efficiently recover the geometric structure of data manifolds even in the case when data are sparse or non-uniformly distributed. Experimental results are presented to illustrate the better performance of ILTSA on both synthetic data and image data. [ABSTRACT FROM AUTHOR]

Abstract: The p13 gene is a group II nucleopolyhedroviruses (NPVs) specific gene and featured by containing upstream mini ORFs (uORF) in its 5′ UTR region. However, there are almost no reports published on the functions of the uORFs of p13 gene. In this study, the Luciferase Reporter Assay System was employed to investigate how the mini ORFs of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) p13 gene (Ha-p13) and its rare codons regulated the downstream gene expression. After the coding sequence of uORFs in the Ha-p13 gene was fused to the luciferase reporter gene in the expression vector pGL3 and the plasmid DNA was then transfected into the Hz-AM1 cells, the translation of the fusion protein could be initiated from the start codon of the uORFs. The uAUG and its context in uORF2 seemed to be more efficient for translation initiation than that in uORF1. Mutation of the start codons in one or both of uORFs (uORF1 or uORF2) could significantly increase the expression of the downstream reporter gene. The start codon mutation in uORF1 produced a higher reporter gene expression than that in uORF2, indicating that the uORF1 could be a stronger inhibitor than the uORF2, and the length of uORFs seemed not to be crucial for down-regulating translation. The expression of both uORFs could co-regulate the associated gene expression. Substituting the rare codons in uORF1, uORF2 or both with less rare codons dramatically increased the expression of the downstream reporter gene. Rare codon mutations in both uORFs were much more efficient in up-regulating the associate gene expression than mutations in either of the two uORFs alone. [ABSTRACT FROM AUTHOR]

The conversional synthesis of taxoids by the BAC sequence from the C19-diterpenoid alkaloids, 14-acetyltalatisamine (1), yunaconitine (12), and 14-acetylchasmanine (19), was designed and explored. Two aconane-type diterpenes 17 and 28, the advanced intermediates for our conversional synthesis, were synthesized. The key steps include the rupture of the C(7)-C(17) bond, the formation of imine, and the denitrogenation. [ABSTRACT FROM AUTHOR]

Because no vaccine or effective therapy is available, thousands of people with HCV have died in recent years. Cytotoxic T lymphocytes (CTLs) play a critical role in the host cellular immune response against HCV. CTL epitopes in HCV core protein have been identified and used in vaccine development. T helper epitopes could promote cytokine secretion and antibody production to fight HCV. Tetanus toxin, an immunogen with many T helper epitopes, was once used in HBV therapeutic vaccine design. Here, eukaryotic and prokaryotic expression vectors were constructed to express truncated fragments of tetanus toxin and core genes of HCV. HLAA2.1 transgenic mice were inoculated with a recombinant plasmid vehicle with these two heterogenic gene fragments, and this augmented the titres of antibody against HCV. Antigen-specific lymphocyte proliferation, Th1 and Th2 cytokine levels and the number of lysed cells were markedly increased in the combined immunization group compared to controls. These findings provide new insights into a potential role for T helper epitopes from tetanus toxin combined with protein from the HCV core gene, which has numerous CTL epitopes. This design strategy may aid in the development of new vaccines against HCV. [ABSTRACT FROM AUTHOR]

Three new C19-diterpenoid alkaloids, umbrosumines A-C (1-3), and 11 known compounds (4-14) were isolated from the roots of Delphinium umbrosum. Their structures were elucidated on the basis of the spectroscopic data interpretation. [ABSTRACT FROM AUTHOR]

HCV is prevailed in the world as well as in China. Blood transfusion is one of the most common transmission pathways of this pathogen. Although data of HCV infection character were reported during the past years, anti-HCV reactive profile of China donors was not fully clear yet. Furthermore, infection progress was found related to the HCV genotype. Different genotype led to different efficacy when interferon was introduced into HCV therapy. Here we provided character data of HCV infection in China blood donors from the year of 2000 to 2009. The infection rate in local donors was lower than general population and descended from 0.80% to 0.40% or so in recent years. About 83% HCV strains were categorized into genotypes 1b and 2a. But 1b subtype cases climbed and 2a subtype cases decreased. The current study threw more light on HCV infection of blood donors in China, at least in the Northern region. [ABSTRACT FROM AUTHOR]