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In this article, we present a corrector-predictor path-following interior-point algorithm forP∗(κ)-horizontal linear complementarity problem over Cartesian product of symmetric cones, using Euclidean Jordan algebras. This comprehensive problem is a newly introduced problem in the context of interior-point methods. The algorithm takes damped Nesterov-Todd steps in the predictor (affine-scaling) stage while maintaining a certain neighborhood of the central path. Moreover, at each corrector stage, we use only full-Nesterov-Todd steps. Furthermore, we derive the currently best known iteration bound for the algorithm with small updates, namely,, whereris the rank of the associated Euclidean Jordan algebra and𝜀is a prescribed tolerance. [ABSTRACT FROM AUTHOR]

In this paper, we propose a feasible interior-point method for convex quadratic programming over symmetric cones. The proposed algorithm relaxes the accuracy requirements in the solution of the Newton equation system, by using an inexact Newton direction. Furthermore, we obtain an acceptable level of error in the inexact algorithm on convex quadratic symmetric cone programming (CQSCP). We also prove that the iteration bound for the feasible short-step method is O(√n log 1 ε), and O(n log 1 ε) for the large-step method which coincide with the currently best known iteration bounds for CQSCPs. [ABSTRACT FROM AUTHOR]

The aim of this paper is to extend the theoretical framework of thehorizontal linear complementarity problem over Cartesian product of symmetric cones (Cartesian-SCHLCP). The concepts of column and row sufficiency are defined for a linear operator on a Euclidean Jordan algebra. Some connections between theproperty of a linear operator on a Euclidean Jordan algebra and itsproperty as well as its column sufficiency are presented. Then these definitions and connections are generalized to a pair of linear operators determining the Cartesian-SCHLCP. It is also demonstrated that the Cartesian-SCHLCP can be equivalent with alinear complementarity problem over Cartesian product of symmetric cones (Cartesian-SCLCP), in a certain sense. Finally, based on some obtained results and using a suitable potential function, the main task of the paper is done, which is to show that the central trajectory of the Cartesian-SCHLCP exists and is unique. Therefore, we open the way for presenting and extending the interior-point methods for the Cartesian-SCHLCP. [ABSTRACT FROM AUTHOR]

Euclidean Jordan algebra is a commonly used tool in designing interior-point algorithms for symmetric cone programs. In this paper, we present a full Nesterov–Todd (NT) step infeasible interior-point algorithm for horizontal linear complementarity problems over Cartesian product of symmetric cones. Since the algorithm uses only full-NT feasibility and centring steps, it has the advantage that no line searches are needed. The complexity result obtained here for symmetric cones using NT directions coincides with the best bound obtained for horizontal linear complementarity problems. [ABSTRACT FROM AUTHOR]

This paper contains an infeasible interior-point method for $$P_*(\kappa )$$ horizontal linear complementarity problem based on a kernel function. The kernel function is used to determine the search directions. These search directions differ from the usually used ones in some interior-point methods, and their analysis is more complicated. Main feature of our algorithm is that there is no calculation of the step size, i.e, we use full-Newton steps at each iteration. The algorithm constructs strictly feasible iterates for a sequence of perturbations of the given problem, close to its central path. Two types of full-Newton steps are used, feasibility steps and centering steps. The iteration bound matches the best-known iteration bound for these types of algorithms. [ABSTRACT FROM AUTHOR]

We present a modified version of the infeasible-interior-point algorithm for monotone linear complementary problems introduced by Mansouri et al. (Nonlinear Anal. Real World Appl. 12(2011) 545{561). Each main step of the algorithm consists of a feasibility step and several centering steps. We use a different feasibility step, which targets at the μ+-center. It results a better iteration bound. [ABSTRACT FROM AUTHOR]

In [H. Mansouri and C. Roos, Numer. Algorithms 52 (2009) 225-255.], Mansouri and Ross presented a primal-dual infeasible interior-point algorithm with full-Newton steps whose iteration bound coincides with the best known bound for infeasible interior-point methods. Here, we introduce a slightly different algorithm with a different search direction and show that the same complexity result is obtained using a simpler analysis. [ABSTRACT FROM AUTHOR]

We present several improvements of the full-Newton step infeasible interior-point method for linear optimization introduced by Roos (SIAM J. Optim. 16(4):1110-1136, ). Each main step of the method consists of a feasibility step and several centering steps. We use a more natural feasibility step, which targets the μ-center of the next pair of perturbed problems. As for the centering steps, we apply a sharper quadratic convergence result, which leads to a slightly wider neighborhood for the feasibility steps. Moreover, the analysis is much simplified and the iteration bound is slightly better. [ABSTRACT FROM AUTHOR]

Introduction: Training breast self-examination by peers provides an appropriate situation in order to form proper health behaviors during the adolescence age. The aim of this study was to compare the effect of training breast self-examination by peers and health care personnel on students' knowledge and attitude. Methods: In this quasi-experimental study, 112 students from two schools of dentistry and management of Shiraz University of Medical Sciences were selected randomly and were allocated in two groups. They were taken a pre-test and two post-tests. Data gathering tool was an assessment test evaluating their knowledge about breast cancer and self-examination and their attitude toward breast self-examination. Four or five students from each class were selected and trained as peer instructors. Students of the first group were trained by peers and the students in the second group were instructed by health care personnel separately using booklet. At the end of educational sessions, the first post-test, and after 6 weeks, the second post-test were taken. Statistical analysis was performed using paired t-test and independent t-test, repeated measure ANOVA, and factor analysis test. Results: There was a significant difference between knowledge and attitude scores of the two groups immediately after education, so that, the mean score of knowledge in the group trained by peers was higher than the one educated by health care personnel. But, no significant difference was observed between the attitude scores of the two groups, 6 weeks after education. Comparing the knowledge and attitude scores, before, immediately after and 6 weeks after education showed a significant difference in each group. Conclusion: The efficacy of training breast self-examination by peers is higher than by health care personnel. It is recommended to employ this educational method more, especially in training self-examination. [ABSTRACT FROM AUTHOR]

Pyk2 is a multi-domain non-receptor tyrosine kinase that serves dual roles as a signaling enzyme and scaffold. Pyk2 activation involves a multi-stage cascade of conformational rearrangements and protein interactions initiated by autophosphorylation of a linker site. Linker phosphorylation recruits Src kinase, and Src-mediated phosphorylation of the Pyk2 activation loop confers full activation. The regulation and accessibility of the initial Pyk2 autophosphorylation site remains unclear. We employed peptide-binding molecularly imprinted nanoparticles (MINPs) to probe the regulatory conformations controlling Pyk2 activation. MINPs differentiating local structure and phosphorylation state revealed that the Pyk2 autophosphorylation site is protected in the autoinhibited state. Activity profiling of Pyk2 variants implicated FERM and linker residues responsible for constraining the autophosphorylation site. MINPs targeting each Src docking site disrupt the higher-order kinase interactions critical for activation complex maturation. Ultimately, MINPs targeting key regulatory motifs establish a useful toolkit for probing successive activational stages in the higher-order Pyk2 signaling complex., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

In situ modification of glycans requires extraordinary molecular recognition of highly complex and subtly different carbohydrates, followed by reactions at precise locations on the substrate. We here report synthetic catalysts that under physiological conditions cleave a predetermined oligosaccharide block such as a branched trimannose or the entire N -glycan of a glycoprotein, while nontargeted glycoproteins stay intact. The method also allows α2-6-sialylated galactosides to be removed preferentially over the α2-3-linked ones from cell surfaces, highlighting the potential of these synthetic glycosidases for glycan editing.

The aggregation of β-amyloid peptides (Aβ), implied in the development and progression of Alzheimer's disease, is driven by a complex set of intramolecular and intermolecular interactions involving both hydrophobic and polar residues. The key residues responsible for the forward assembling process may be different from those that should be targeted to disassemble already formed aggregates. Molecularly imprinted nanoparticle (MINP) receptors are reported in this work to strongly and selectively bind specific segments of Aβ 40 . Combined fluorescence spectroscopy, atomic force microscopy (AFM) imaging, and circular dichroism (CD) spectroscopy indicate that binding residues 21-30 near the loop region is most effective at inhibiting the aggregation of monomeric Aβ 40 , but residues 11-20 that include the internal β strand closer to the N-terminal represent the best target for disaggregating already formed aggregates in the polymerization phase. Once the aggregation proceeds to the saturation phase, binding residues 1-10 has the largest effect on the disaggregation, likely because of the accessibility of these amino acids relative to others to the MINP receptors.

Enzyme-like catalysts by design have been a long sought-after goal of chemists but difficult to realize due to the challenges in the construction of multifunctionalized active sites with accurately positioned catalytic groups for complex substrates. Hydrolysis of cellulose is a key step in biomass utilization and requires multiple enzymes to work in concert to overcome the difficulty associated with hydrolyzing the recalcitrant substrate. We here report methods to construct synthetic versions of these enzymes through covalent molecular imprinting and strategic postmodification of the imprinted sites. The synthetic catalysts cleave a cellulose chain endolytically at multiple positions or exolytically from the nonreducing end by one or three glucose units at a time, all using the dicarboxylic acid motif found in natural cellulases. By mimicking the endocellulase, exocellulase, and β-glucosidase, the synthetic catalysts hydrolyze cellulose in a synergistic manner, with an activity at 90 °C in pH 6.5 buffer more than doubled that of Aspergillus niger cellulase at pH 5 and 37 °C and 44% of that of a commercial cellulase blend (from Novozyme). As robust cross-linked polymeric nanoparticles, the synthetic catalysts showed little changes in activity after preheating at 90 °C for 3 days and could be reused, maintaining 76% of activity after 10 reaction cycles.

Protection/deprotection is a powerful strategy in the total synthesis of complex organic molecules but similar tools are nearly absent in enzymatic reactions. We here report supramolecular protective receptors that outcompete an enzyme in the binding of oligosaccharides. The strong binding inhibits the enzymatic reaction and addition of an even stronger ligand for the receptor releases the substrate. These receptors could be used to control products from the same substrate/enzyme mixture and regulate enzymatic reactions reversibly.

Lytic polysaccharide monooxygenases (LPMOs) cleave polysaccharides through copper-bound oxyl radicals. We report a synthetic mimic of LPMO that uses micelle-stabilized hydrogen bonds to bind a glycan and two molecularly imprinted hydrophobic pockets to accommodate the alkyl tail of the glycoside and a copper cofactor, respectively. Cleavage of alkyl glycosides and oligosaccharides with hydrogen peroxide occurs at room temperature in aqueous solution, with selectivities for both the glycan and the alkyl aglycon.

Molecular imprinting is a powerful and yet simple method to create multifunctional binding sites within a cross-linked polymer network. We report a new class of synthetic glucosidase prepared through molecular imprinting and postfunctionalization of cross-linked surfactant micelles. These catalysts are protein-sized water-soluble nanoparticles that can be modified in multiple ways. As their natural counterparts, they bind a glucose-containing oligo- or polysaccharide. They contain acidic groups near the glycosidic bond to be cleaved, with the number and distance of the acid groups tuned systematically. Hydrolysis of cellulose in a key step in biomass conversion but is hampered by the incalcitrance of the highly crystalline cellulose fibers. The synthetic glucosidases are shown to hydrolyze cellobiose and cellulose under a variety of conditions. The best catalyst, with a biomimetic double acid catalytic motif, can hydrolyze cellulose with one-fifth of the activity of commercial cellulases in aqueous buffer. As a highly cross-linked polymeric nanoparticle, the synthetic catalyst is stable at elevated temperatures in both aqueous and nonaqueous solvents. In a polar aprotic solvent/ionic liquid mixture, it hydrolyzes cellulose several times faster than commercial cellulases in aqueous buffer. When deposited on magnetic nanoparticles, it retains 75% of its activity after 10 cycles of usage.

Although synthetic mimics of lectins can be extremely useful in biological and biomedical research, molecular recognition of carbohydrates has been hampered by their strong solvation in water and subtle structural differences among analogues. Molecularly imprinted nanoparticle receptors were prepared with glycans directly cleaved from glycoproteins. Functionalized with boroxole groups in the binding sites, these water-soluble synthetic lectins bound the parent glycoproteins selectively in water with an association constant of K a = 10 4 -10 5 M -1 . The strong binding enabled the receptors to protect the targeted glycans from enzymatic cleavage. When clicked onto magnetic nanoparticles, the receptors enabled facile isolation of glycoproteins from a mixture.

Synthetic receptors to recognize biological glycans are in great need for modern glycoscience and technology, but their design and synthesis have been a daunting challenge due to strong solvation of carbohydrates in water and structural complexity of the guest. Molecular imprinting in surfactant micelles with amide cross-linkers provides a convenient one-pot method to prepare nanoparticle receptors for glycosides, glycans, and glycoproteins, taking advantage of hydrogen-bonding interactions near the surfactant/water interface. Biologically competitive micromolar binding affinities were obtained in water and subtle structural differences of glycans could be distinguished.