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We introduce a high-dimensional analogue of the Kirchhoff index which is also known as total effective resistance. This analogue, which we call the simplicial Kirchhoff index K f ( X ) , is defined to be the sum of the simplicial effective resistances of all ( d + 1 ) -subsets of the vertex set of a simplicial complex X of dimension d. This definition generalizes the Kirchoff index of a graph G defined as the sum of the effective resistance between all pairs of vertices of G. For a d-dimensional simplicial complex X with n vertices, we give formulas for the simplicial Kirchhoff index in terms of the pseudoinverse of the Laplacian L X in dimension d − 1 and its eigenvalues: K f ( X ) = n ⋅ tr L X + = n ⋅ ∑ λ ∈ Λ + 1 λ , where L X + is the pseudoinverse of L X , and Λ + is the multi-set of non-zero eigenvalues of L X . Using this formula, we obtain an inequality for a high-dimensional analogue of algebraic connectivity and Kirchhoff index, and propose these quantities as measures of robustness of simplicial complexes. In addition, we derive its integral formula and relate this index to a simplicial dynamical system. We present an open problem for a combinatorial proof of our formula by relating the combinatorial interpretation of R σ to rooted forests in higher dimensions.

We propose a new centrality incorporating two classical node-level centralities, the degree centrality and the information centrality, which are considered as local and global centralities, respectively. These two centralities have expressions in terms of the graph Laplacian L, which motivates us to exploit its fractional analog L^{γ} with a fractional parameter γ. As γ varies from 0 to 1, the proposed fractional version of the information centrality makes intriguing changes in the node centrality rankings. These changes could not be generated by the fractional degree centrality since it is mostly influenced by the local aspect. We prove that these two fractional centralities behave similarly when γ is close to 0. This result provides its complete understanding of the boundary of the interval in which γ lies since the fractional information centrality with γ=1 is the usual information centrality. Moreover, our computation for the correlation coefficients between the fractional information centrality and the degree centrality reveals that the fractional information centrality is transformed from a local centrality into being a global one as γ changes from 0 to 1.

High-dimensional networks are a topological generalization of electrical networks. As combinatorial invariants of electrical networks often require enumeration of trees, their high-dimensional analogues are also based on torsion-weighted enumeration of acyclic subcomplexes over the reals. In this paper, for a high-dimensional network with a current generator, we express a current vector and a voltage vector in terms of high-dimensional forests. To this end, we introduce a new simple method, an acyclization in codimension 1, for computing forest-numbers.

Bicyclization has proven to be an effective strategy for significantly restricting conformational flexibility in peptides and peptidomimetics such as peptoids. Such constrained bicyclic peptoids would have far higher conformational rigidity than monocyclic and linear ones, allowing them to have enhanced binding affinity and selectivity for their biological targets. Herein, we show that bicyclic peptoids have superior cellular uptake efficiency than their linear counterparts regardless of their side chains and ring sizes. As a representative example, an 8-mer bicyclic peptoid achieves a CP

Here we describe the design and synthesis of a DNA-encoded library of bicyclic peptoids. We show that our solid-phase strategy is facile and DNA-compatible, yielding a structurally diverse combinatorial library of bicyclic peptoids of various ring sizes. We also demonstrate that affinity-based screening of a DNA-encoded library of bicyclic peptoids enables to efficiently identify high-affinity ligands for a target protein. Given their highly constraint structures, as well as increased cell permeability and proteolytic stability relative to native peptides, bicyclic peptoids could be an excellent source of protein capture agents. As such, our DNA-encoded library of bicyclic peptoids will serve as versatile tools that facilitate the generation of potent ligands against many challenging targets, such as intracellular protein-protein interactions.

For a network G, we introduce a non-singular symmetric matrix, called a path intersection matrix, that will provide a new method for computing the ratio k ( G ) / k ( G / a b ) where k ( G ) is the tree-number of G and G / a b is obtained from G ∪ a b by contracting the new edge ab between two distinct nodes a and b. The quantities k ( G ) / k ( G / a b ) appear as invariants for various networks such as effective conductance for an electrical network and an ingredient for information centrality for a social network. We will review several examples of networks where path intersection matrices can be applied.

We report the design and synthesis of a DNA-encoded one-bead one-compound library of cyclic peptoids composed of more than 11 million molecules. We show that affinity-based screening of this large library can identify cyclic peptoid ligands for a target protein. In this work, we developed a simple method for amplifying the PCR product from DNA tags on a single bead, thereby enabling determination of the structures of hit cyclic peptoids with no need for high-throughput sequencing and complicated data analysis. We also developed a sublibrary screening strategy to minimize false positives caused by the interference of coding DNA tags before starting laborious and impractical hit confirmation. Given the simplicity and robustness of the synthesis and screening, along with the desirable features of macrocyclic peptoids including improved conformational rigidity, our method will be highly useful for discovering biologically active molecules modulating challenging targets such as protein-protein interactions that are not easily targeted by typical peptidomimetics and small-molecules.

Peptoids, oligomers of N-substituted glycines, have been attracting increasing interest due to their advantageous properties as peptidomimetics. However, due to the lack of chiral centers and amide hydrogen atoms, peptoids, in general, do not form folding structures except that they have α-chiral side chains. We have recently developed "peptoids with backbone chirality" as a new class of peptoid foldamers called α-ABpeptoids and demonstrated that they could have folding conformations owing to the methyl groups on chiral α-carbons in the backbone structure. Here we report α-ABpeptoid/β3 -peptide oligomers as a unique peptidomimetic structure with a heterogeneous backbone. This hybrid structure contains a mixed α-ABpeptoid and β3 -peptide residues arranged in an alternate manner. These α-ABpeptoid/β3 -peptide oligomers could form intramolecular hydrogen bonding and have better cell permeability relative to pure peptide sequences. These oligomers were shown to adopt ordered folding structures based on circular dichroism studies. Overall, α-ABpeptoid/β3 -peptide oligomers may represent a novel class of peptidomimetic foldamers and will find a wide range of applications in biomedical and material sciences.

The development of peptidomimetic foldamers that can form well-defined folded structures is highly desirable yet challenging. We previously reported on &alpha, ABpeptoids, oligomers of N-alkylated &beta, 2-homoalanines and found that due to the presence of chiral methyl groups at &alpha, positions, &alpha, ABpeptoids were shown to adopt folding conformations. Here, we report &beta, ABpeptoids having chiral methyl group at &beta, positions rather than &alpha, positions as a different class of peptoids with backbone chirality. We developed a facile solid-phase synthetic route that enables the synthesis of &beta, ABpeptoid oligomers ranging from 2-mer to 8-mer in excellent yields. These oligomers were shown to adopt ordered folding conformations based on circular dichroism (CD) and NMR studies. Overall, these results suggest that &beta, ABpeptoids represent a novel class of peptidomimetic foldamers that will find a wide range of applications in biomedical and material sciences.

Peptoids, oligomers of N-substituted glycines, have been attracting increasing interest due to their advantageous properties as peptidomimetics. However, due to the lack of chiral centers and amide hydrogen atoms, peptoids, in general, do not form folding structures except that they have α-chiral side chains. We have recently developed "peptoids with backbone chirality" as a new class of peptoid foldamers called α-ABpeptoids and demonstrated that they could have folding conformations owing to the methyl groups on chiral α-carbons in the backbone structure. Here we report α-ABpeptoid/β

A novel submonomer solid-phase synthetic method for α-ABpeptoid oligomers is reported. Iterative submonomer coupling and Fukuyama-Mitsunobu alkylation enable facile, divergent synthesis of α-ABpeptoid oligomers substituted with chemically diverse side chains in excellent yields.

This study investigates the quality characteristics of muffins prepared with various concentrations of akebia leaves powder. Muffins are prepared by additions of 0%, 2%, 4%, 6% and 8% powder to the flour for basic formulation. Heights decrease significantly when the amount of Akebia leaves powder increases. When the weight is being measured, there are no meaningful differences between the samples. As a result from measuring the colors, the lightness, redness and yellowness of muffins decrease as the concentrations of the powder increase. When measuring the texture of akebia leaves muffins, the hardness, cohesiveness, gumminess and chewiness decrease, but the springiness and adhesiveness increase as the concentrations of Akebia leaves powder increase. When the sensual qualities of the muffins are measured, the color, sweetness, softness and overall quality of all of the samples have shown significant differences, and the muffins containing 4% of Akebia leaves powder reveal the highest sensual quality indexes.Key words: Akebia quinata leaves, muffins, quality characteristics

A new class of peptoid-based peptidomimetics composed of oligomers of N-substituted β(2)-homoalanines is reported. Design, solid-phase synthesis, and preliminary circular dichroism studies of oligomers of N-alkylated β(2)-homoalanines consisting of up to 8-mers are described.

In this paper, Capacitance-Voltage (CV) measurements as a powerful technique to analyze electric properties of Top emitting OLED (TOLED) devices are introduced. After comparing CV characteristics between inverted TOLED and conventional TOLED with thin metal, it is found that inverted OLED struggles charge injection, especially electron injection. Here Current-Voltage-Luminance (IVL) and CV characteristics are carefully analyzed for single carrier devices and dual carrier devices systematically. Top emitting OLED (TOLED) with thin metal cathode shows more efficient electron injection and higher efficiency than that of inverted OLED, which is attributed to the order of thermal deposition of organic/metal layers.

Using variable-angle spectroscopic ellipsometry, we measure the pseudo-dielectric functions of as-deposited and annealed SiO2/SiOx multilayers. The SiO2(2 nm)/SiOx(2 nm) multilayers are prepared under various deposition temperatures by ion beam sputtering. Annealing at temperatures above 1100 °C leads to the formation of Si nanocrystals (nc-Si) in the SiOx layer of multilayers. Transmission electron microscopy images clearly demonstrate the existence of nc-Si. We assume a Tauc–Lorentz lineshape for the dielectric function of nc-Si, and use an effective medium approximation for SiO2/nc-Si multilayers as a mixture of nc-Si and SiO2. We successfully estimate the dielectric function of nc-Si and its volume fraction. We find that the volume fraction of nc-Si decreases after annealing, with increasing x in as-deposited SiOx layer. This result is compared to expected nc-Si volume fraction, which is estimated from the stoichiometry of SiOx.

We have measured the dielectric function of poly 2-methoxy-5-hexyloxy phenylenevinylene and the alternating copolymers with N-hexylphenothiazine grown on glass using variable angle spectroscopic ellipsometry and Raman spectroscopy at room temperature. Using the parametric optical constant model, we estimated the dielectric function of each polymer and also determined the band gap parameters, such as threshold energy, broadening, and amplitude. We also determined the band gap parameters by performing lineshape curve-fitting on the second derivative of the fit dielectric function using standard critical point model, and compared to those of the parametric optical constant model. We discussed the shift of band gap parameters and phonon wave numbers in terms of the chemical structures.

We give a new formula for the weighted high-dimensional tree-numbers of matroid complexes. This formula is derived from our result that the spectra of the weighted combinatorial Laplacians of matroid complexes consist of polynomials in the weights. In the formula, Crapo’s $\beta$-invariant appears as the key factor relating weighted combinatorial Laplacians and weighted tree-numbers for matroid complexes., Nous présentons une nouvelle formule pour les nombres d’arbres pondérés de grande dimension des matroïdes complexes. Cette formule est dérivée du résultat que le spectre des Laplaciens combinatoires pondérés des matrides complexes sont des polynômes à plusieurs variables. Dans la formule, le $\beta$;-invariant de Crapo apparaît comme étant le facteur clé reliant les Laplaciens combinatoires pondérés et les nombres d’arbres pondérés des matroïdes complexes.

A facile method for sequence determination of cyclic peptides/peptoids is described. Macrocyclic peptides/peptoids of 3–10 residues were efficiently synthesized through thioether formation. One-pot reaction of thioether-embedded cyclic peptides/peptoids involving cyanogen bromide-mediated ring-opening and cleavage provides linearized molecules, which can be efficiently sequenced by tandem mass spectrometry.

The objectives of this work are to present the dynamic simulation strategy based on clustermodular approach and to develop a prototype simulator. In addition, methods for the improvement of computational efficiency and applicability are studied. A process can be decomposed into several clusters which consist of strongly coupled units depending upon the process dynamics or topology. The combined approach of simultaneous and sequential simulation based on the cluster structure is implemented within the developed dynamic process simulator, MOSA (Multi Objective Simulation Architecture). Dynamic simulation for a utility plant is presented as a case study in order to prove the efficiency and flexibility of MOSA.

Process simulation is essential to the economic evaluation and the reliability or safety analysis of a chemical process. However, conventional similators do not provide users with the information on the accuracy of the results or on the effects of the uncertainties in the data used in the simulation. Therefore, a new simulation method is required which deals with uncertainties in the input variables and in the model parameters. A methodology for stochastic simulation is proposed in this paper, which is based on Monte Carlo simulation. The results of sensitivity analysis numerically and graphically show the trend of the change in the uncertainties of the process variables, changes in the importance of the variables, and the relations between the variables. The proposed approach was implemented in a general purpose dynamic process simulator, MOSA, and showed good applicabilities for chemical processes with various uncertainties. One of the most important advantages of the proposed method is that it can use the deterministic models used in the conventional simulators without any modifications.

A dynamic simulation strategy based on modular approach is presented and its implementation is described. The modular approach is very appealing to engineers, as it is easy to understand and to make use of well-established knowledge of each module. A process can be partitioned into several clusters which consist of strongly coupled units according to the process dynamics or topology. A mixed form of simultaneous and sequential simiilation based on this cluster is implemented as a prototype dynamic process simulator, MOSA. Currently, ODE mode simulation for solving dynamic model equations is used because it is relatively easy to implement.

This paper presents an efficient homotopy continuation method to solve a nonlinear eqaution system which describes chemical engineering problems. The characteristics of the Newton homotopy function is studied and parametric continuation is proposed to study steady state multiplicities for a constrained system. An equation based distillation simulator employing the proposed algorithm was implemented. The proposed algorithm and simulator were tested on many numerical problems and complex distillation columns.

Objectives: This study investigated the busyness of dentists and analyzed factors related to busyness in these professionals. Methods: The subjects were 243 practicing dentists. Surveys were carried out via mail. Busyness was measured by using the Mumma scale. The data were analyzed using the Kruskal-Wallis test. Results: The dentists’ busyness index was 1.91. Of the participants, 40% of practicing dentists wanted more patients, 30.8% did not overwork but did not want more patients, and 27.1% overworked and did not want more patients. The busyness index was significantly related to the number of dental hygienists and dentists. However, it did not differ with respect to the number of assistant nurses. Conclusions: The busyness index should be considered when developing relevant human resource plans.