bluuebunny/crossref_metadata_2025 huggingface dataset:
Capacitive methods for testing of power semiconductor devices
Authors: Papez Vaclav , Hájek Jiri , Kojecký Bedrich
Published: July 2015

Electrical capacity of power semiconductor devices is quite an important
parameter that can be utilized not only for testing a component itself, but
it can also be applied practically; e.g. in series-connected high voltage
devices. This paper first analyzes the theoretical voltage distribution on
the bases of the polarized p-n junction, as well as the size of capacity. The
measurement of the voltage-capacity dependence using the resonance principle
is illustrated on the samples of 4kV and 6kV thyristors. The correspondence
between theoretical estimation of the capacity, measured voltage capacity
dependence based on the resonance principle and experimentally determined by
injected charge proves the correctness of the applied procedures and
assumptions.
Carboxymethyl cellulase production from a Paenibacillus sp.
Authors: Mihajlovski Katarina , Davidovic Sladjana , Carevic Milica , Radovanovic Neda , Siler-Marinkovic Slavica , Rajilic-Stojanovic Mirjana , Dimitrijevic-Brankovic Suzana
Published: July 2015

Cellulases are industrially important enzymes with a potential to convert
cellulose into fermentable sugars. Novel bacterial isolate Paenibacillus sp.
CKS1 was tested for cellulase activity and the optimal conditions for
carboxymethyl cellulase (CMCase) production were determined. Maximum CMCase
activity was obtained in the third passage of the bacterial culture after 3
days of incubation at 30?C. Cellobiose and yeast extract was the optimal
source of carbon and nitrogen for induction of CMCase activity. In addition,
with initial pH 7 of the medium and 40 ml of working volume in 500 ml culture
flasks with shaking at 150 rpm, the maximum CMCase activity in a crude
culture supernatant reached value of 0.532?0.006 U/ml. For crude CMCase,
optimal temperature was 50?C and optimal pH 4.8, respectively. HPLC analysis
confirmed the bacterium is capable to hydrolise CMC to glucose and other
soluble sugars.
Rise of the aesthetic experience and the crisis of the aesthetic values
Authors: Cuckovic Aleksandar
Published: July 2015

The possibility of aesthetic experience is in recent years more common than
ever, because of the different contents that are being more and more invested
with the aesthetic properties. They originate from the very different
sources, first of all, from the artistic production and the mass reproduction
of the artifacts, then, from the whole human artificial environment, where
the mass media play an prominent role, but from the social rituals and
ceremonies and from the individually chosen ?lifestyles? as well. Although
the notion of the ?aesthetic experience? overpowered the traditionally
dominant concept of ?beauty? in the modern aeshtetics, the nature of its
value still initiates the debates, because the experiences are more numerous
than their holders. The excellence of art has been merged in the banality of
everyday life, which obtained an attractive appearance, but not the beauty of
spirit, lovable surface, but not the true depth. As a strategy of turning the
unaesthetic to aesthetic, aestheticization would be more promising if it
would not be reduced to the mere anaesthetic technique of beautification, but
if it would be the trigger for the legitimation of pervasive interference of
all of the domains of rationality, which are still seen irreconcilable and,
therefore, as usurpative.
σ-ring and σ-algebra of Sets1
Authors: Endou Noboru , Nakasho Kazuhisa , Shidama Yasunari
Published: July 2015

In this article, semiring and semialgebra of sets are formalized so as to construct a measure of a given set in the next step. Although a semiring of sets has already been formalized in [13], that is, strictly speaking, a definition of a quasi semiring of sets suggested in the last few decades [15]. We adopt a classical definition of a semiring of sets here to avoid such a confusion. Ring of sets and algebra of sets have been formalized as non empty preboolean set [23] and field of subsets [18], respectively. In the second section, definitions of a ring and a σ-ring of sets, which are based on a semiring and a ring of sets respectively, are formalized and their related theorems are proved. In the third section, definitions of an algebra and a σ-algebra of sets, which are based on a semialgebra and an algebra of sets respectively, are formalized and their related theorems are proved. In the last section, mutual relationships between σ-ring and σ-algebra of sets are formalized and some related examples are given. The formalization is based on [15], and also referred to [9] and [16].
Separability of Real Normed Spaces and Its Basic Properties
Authors: Nakasho Kazuhisa , Endou Noboru
Published: July 2015

In this article, the separability of real normed spaces and its properties are mainly formalized. In the first section, it is proved that a real normed subspace is separable if it is generated by a countable subset. We used here the fact that the rational numbers form a dense subset of the real numbers. In the second section, the basic properties of the separable normed spaces are discussed. It is applied to isomorphic spaces via bounded linear operators and double dual spaces. In the last section, it is proved that the completeness and reflexivity are transferred to sublinear normed spaces. The formalization is based on [34], and also referred to [7], [14] and [16].
Equivalent Expressions of Direct Sum Decomposition of Groups1
Authors: Nakasho Kazuhisa , Okazaki Hiroyuki , Yamazaki Hiroshi , Shidama Yasunari
Published: July 2015

In this article, the equivalent expressions of the direct sum decomposition of groups are mainly discussed. In the first section, we formalize the fact that the internal direct sum decomposition can be defined as normal subgroups and some of their properties. In the second section, we formalize an equivalent form of internal direct sum of commutative groups. In the last section, we formalize that the external direct sum leads an internal direct sum. We referred to [19], [18] [8] and [14] in the formalization.
Assessment of Person Fit for Mixed-Format Tests
Authors: Sinharay Sandip
Published: July 2015

Person-fit assessment may help the researcher to obtain additional information regarding the answering behavior of persons. Although several researchers examined person fit, there is a lack of research on person-fit assessment for mixed-format tests. In this article, the lz statistic and the ζ2 statistic, both of which have been used for tests with only dichotomous items or with only polytomous items, were modified for use with mixed-format tests. In a detailed simulation, the lz and ζ2 statistics are found to be conservative under a (frequentist) asymptotic normal approximation. However, the use of the statistics along with the (Bayesian) posterior predictive model checking method leads to a larger power. The suggested approaches are applied to an operational data set. The approaches appear to be satisfactory tools for assessing person fit for mixed-format tests.
Antioxidant capacity and kinetics of dendritic hindered phenols using DPPH assay
Authors: Li Cuiqin , Wei Yujia , Shi Weiguang , Wang Jun , Wang Baohui
Published: July 2015

Dendritic hindered phenols were synthesised using 3-(3,5-di-tert-butyl-4-hydroxy-phenyl)-propionic acid and dendritic poly(amido-amine) (PAMAM) as materials. The structures of the dendritic hindered phenols were characterised by infrared spectroscopy (FTIR), 1H-nuclear magnetic resonance spectroscopy (1H NMR) and liquid chromatography–mass spectrometry (LC-MS). The scavenging capacity and kinetics of the dendritic hindered phenols were investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. These dendritic hindered phenols have excellent scavenging capacity, being superior to antioxidants 1010 and 1098 with the same number of phenol hydroxyl groups. The scavenging capacity of the first-generation dendritic hindered phenol (1.0G dendritic phenol) was superior to that of the second-generation dendritic hindered phenol (2.0G dendritic phenol). The kinetic behaviour of the hindered phenols in scavenging the DPPH radical was a first-order reaction. The scavenging rate constants ( k1) of the dendritic phenols with DPPH radical were higher than that of antioxidants 1010 and 1098, while the k1 value of 1.0 G dendritic phenol was superior to that of 2.0 G dendritic phenol under the same test conditions. The scavenging activation energy ( Ea) of 1.0 dendritic phenol with four phenolic groups and two tertiary amine groups was the lowest, while that of antioxidant 1010 with a higher molecular weight and four phenolic groups was the greatest.
Self-Correcting Neural Network for Stereo-matching Problem Solving
Authors: Laskowski Lukasz , Jelonkiewicz Jerzy
Published: July 2015

In the present paper we describe innovative architecture of artificial neural network based on Hopfield structure - Self Correcting Neural Network (SCNN). It is implementation similar to dual mode Hopfield-like network for solving stereo matching problem. Considered network consists of basic layer of neurons implemented as analogue Hopfield-like network and supervising layer. Thanks to the supervising layer, there is a possibility of modification of the connection weights between the neurons in the basic layer. This enables the improvement of the network performance (accuracy). Authors propose a depth map use for image segmentation and objects auto-selection. High enough accuracy of these processes can be achieved when proposed network (SCNN) is applied. Similar idea can be applied also for images noise removal. In the present article we also describe in detail neurons dynamics in the basic and supervising layers of the SCNN.

The network considered here was a subject of experimental tests using real stereo pictures as well as simulated stereo images. This enabled calculation of error and direct comparison with classic analogue Hopfield neural network.
Immunological Computation for Protein Function Prediction
Authors: Zekri Meriem , Alem Karima , Souici-Meslati Labiba
Published: July 2015

Immunological computation is one of the largest recent bio-inspired approaches of artificial intelligence. Artificial immune systems (AIS) are inspired by the processes of the biological immune systems like the learning and memory characteristics which are used for solving complex problems. During the last two decades, AIS have been applied in various fields such as optimization, network security and data mining. In this article, we focus on the application of AIS to data mining in bioinformatics, more specifically, the classification task. For this purpose, we suggest three immune models based on clonal selection theory for the identification of G-protein coupled receptors (GPCRs) to predict their function. Our three classifiers are the artificial immune recognition system (AIRS), the clonal selection algorithm (CLONALG) and the clonal selection classification algorithm (CSCA). The GPCRs represent one of the largest and most important families of multifunctional proteins and are a significant target for bioactive and drug discovery programs. It is estimated that more than half of the drugs on the market currently target GPCRs. However, although thousands of GPCRs sequences are known, many of them remain orphans, have unknown function. Our experiments show that the three immunological classifiers have provided interesting results, however, AIRS obtained the best ones. Therefore, it is, for us, the most suitable immune model for the GPCRs identification problem.
Simple Linear Comparison of Strings in V-order
Authors: Alatabbi Ali , Daykin Jacqueline W. , Rahman M. Sohel , Smyth William F.
Published: July 2015

In this paper we focus on a total (but non-lexicographic) ordering of strings called V-order. We devise a new linear-time algorithm for computing the V-comparison of two finite strings. In comparison with the previous algorithm in the literature, our algorithm is both conceptually simpler, based on recording letter positions in increasing order, and more straightforward to implement, requiring only linked lists.
Mesh Algorithms for Coxeter Spectral Classification of Cox-regular Edge-bipartite Graphs with Loops, I. Mesh Root Systems
Authors: Kasjan Stanisław , Simson Daniel
Published: July 2015

This is the first part of our two part paper with the same title. Following our Coxeter spectral study in [Fund. Inform. [123(2013), 447-490] and [SIAM J. Discr. Math. 27(2013), 827-854] of the category 𝒰ℬigrn of loop-free edge-bipartite (signed) graphs Δ, with n ≥ 2 vertices, we study here the larger category ℛℬigrn of Cox-regular edge-bipartite graphs Δ (possibly with dotted loops), up to the usual ℤ-congruences ~Z and ≈Z. The positive graphs Δ in ℛℬigrn, with dotted loops, are studied by means of the complex Coxeter spectrum speccΔ ⊂ℂ, the irreducible mesh root systems of Dynkin types 𝔹n, n≥2,ℂn, n≥3, 𝔽4, 𝔾2, the isotropy group Gl( n, ℤ)Δ (containing the Weyl group of Δ), and by applying the matrix morsification technique introduced in [J. Pure A ppl. Algebra 215(2011), 13-24] and [Fund. Inform. [123(2013), 447-490].

One of our aims of the paper is to study the Coxeter spectral analysis question: “ Does the congruence Δ ≈ℤ Δ′ hold, for any pair of connected positive graphs Δ, Δ′∈ℛℬigrn such that speccΔ=speccΔ′ and the numbers of loops in Δ and Δ′ coincide?” We do it by a reduction to the Coxeter spectral study of the G1(n, ℤ)D-orbits in the set MorD ⊂ 𝕄n(ℤ) of matrix morsifications of a Dynkin diagram D=DΔ∈𝒰Bigrn associated with Δ. In particular, we construct in the second part of the paper numeric algorithms for computing the connected positive edge-bipartite graphs Δ in ℛℬigrn, for a fixed n ≥ 2, mesh algorithms for computing the set of all ℤ-invertible matrices B ∈ G1(n, ℤ) definining the ℤ-congruence Δ≈ℤΔ', for positive graphs Δ, Δ′∈ℛℬigrn, with n ≥ 2 fixed, and mesh-type algorithms for the mesh root systems Γ(RΔ•,ΦΔ). In the first part of the paper we present an introduction to the study of Cox-regular edge-bipartite graphs Δ with dotted loops in relation with the irreducible reduced root systems and the Dynkin diagrams ℬn, n≥2, ℂn, n≥3, 𝔽4,𝔾2. Moreover, we construct a unique ΦD-mesh root system Γ(RD•, ΦD) for each of the Cox-regular edge-bipartite graphs ℬn, n≥2, Cn, n≥3, ℱ4, cal𝒢2 of the type ℬn, n≥2, ℂn, n≥3, 𝔽4,𝔾2, respectively.

Our main inspiration for the study comes from the representation theory of posets, groups and algebras, Lie theory, and Diophantine geometry problems.
A P_Lingua Based Simulator for P Systems with Symport/Antiport Rules
Authors: Macías-Ramos Luis F. , Valencia-Cabrera Luis , Song Bosheng , Song Tao , Pan Linqiang , Pérez-Jiménez Mario J.
Published: July 2015

Inspired by mitosis process and membrane fission processes, cell-like P systems with symport/antiport rules and membrane division rules or membrane separation rules have been introduced, respectively. These computation systems have two key features: the ability to have infinite copies of some objects (within an active environment) and to generate an exponential workspace in polynomial time. In this work, we extend the P-Lingua framework for simulating that kind of P systems taking into account these two features. Consequently, a new simulator has been developed and included in pLinguaCore library. The functioning of the simulator has been checked by simulating efficient solutions to SAT problem using a family of cell-like P systems with symport/antiport rules and membrane division rules or membrane separation rules. The corresponding MeCoSim based application is also provided.
Latency of Neighborhood Based Recommender Systems
Authors: Chojnacki Szymon , Kłopotek Mieczysław
Published: July 2015

Latency of user-based and item-based recommenders is evaluated. The two algorithms can deliver high quality predictions in dynamically changing environments. However, their response time depends not only on the size, but also on the structure of underlying datasets. This constitutes a major drawback when compared to two other competitive approaches i.e. content-based and model-based systems. Therefore, we believe that there exists a need for comprehensive evaluation of the latency of the two algorithms.

During a typical worst case scenario analysis of collaborative filtering algorithms two assumption are made. The first assumption says that data are stored in dense collections. The second assumption states that large amount of computations can be performed in advance during the training phase. As a result it is advised to deploy user-based system when the number of users is relatively small. Item-based algorithms are believed to have better technical properties when the number of items is small.

We consider a situation in which the two assumptions are not necessarily met. We show that even though the latency of the two methods depends heavily on the proportion of users to items, this factor does not differentiate the two methods. We evaluate the algorithms with several real-life datasets. We augment the analysis with both graph-theoretical and experimental techniques.
On Promptness in Parity Games
Authors: Mogavero Fabio , Murano Aniello , Sorrentino Loredana
Published: July 2015

Parity games are infinite-duration two-player turn-based games that provide powerful formal-method techniques for the automatic synthesis and verification of distributed and reactive systems. This kind of game emerges as a natural evaluation technique for the solution of the μ-calculus model-checking problem and is closely related to alternating ω-automata. Due to these strict connections, parity games are a well-established environment to describe liveness properties such as “every request that occurs infinitely often is eventually responded”. Unfortunately, the classical form of such a condition suffers from the strong drawback that there is no bound on the effective time that separates a request from its response, i.e., responses are not promptly provided. Recently, to overcome this limitation, several variants of parity game have been proposed, in which quantitative requirements are added to the classic qualitative ones. In this paper, we make a general study of the concept of promptness in parity games that allows to put under a unique theoretical framework several of the cited variants along with new ones. Also, we describe simple polynomial reductions from all these conditions to either Büchi or parity games, which simplify all previous known procedures. In particular, they allow to lower the complexity class of cost and bounded-cost parity games recently introduced. Indeed, we provide solution algorithms showing that determining the winner of these games is in UPTIME ∩ COUPTIME.
A High Percentage of Beef Bull Pictures in Semen Catalogues Have Feet and Lower Legs that Are Not Visible
Authors: Franks Marcy , Grandin Temple
Published: July 2015

A total of 1379 beef bull pictures were surveyed to determine visibility of feet and legs from four American semen company websites. Five different breeds were represented: Angus, Red Angus, Hereford (polled and horned), Simmental, and Charolais. In addition to visibility, data on other variables were collected to establish frequencies and correlations. These included breed, color, material that obscured visibility, such as grass, picture taken at livestock show or outside, semen company, photographer, video, and age of bull. A foot and leg visibility score was given to each bull picture. Only 19.4% of the pictures had fully visible feet and legs. Both the hooves and dewclaws were hidden on 32.5% of the pictures. Correlation between bull’s birthdate and the first four visibility scores was statistically significant (P < 0.0001). As age increased the feet and legs were more likely to be visible in the bull’s picture. This may possibly be due to greater availability of both photo editing software and digital photography. One positive finding was that 6% of the bulls had a video of the bull walking which completely showed his feet and legs.
Prediction of Experimental Rainfall-Eroded Soil Area Based on S-Shaped Growth Curve Model Framework
Authors: Nie Wen , Huang Run-Qiu , Zhang Qian-Gui , Xian Wei , Xu Feng-Lin , Chen Lin
Published: July 2015

Rainfall-induced soil erosion of a mountain area plays a significant role in supplying sediment and shaping the landscape. The related area of soil erosion, as an index of the changed landscape, is easier to calculate visually using some popular imaging tools. By image analysis, our work shows that the changing of the soil erosion area admits the structure of an S-growth curve. Therefore, we propose to establish an S-curve model, based on incremental learning, to predict the soil erosion area. In the process of incremental learning, we dynamically update the accumulative rainfall and rainfall intensity to train the parameters of our S-curve model. In order to verify our prediction model, the index of area is utilized to express the output of eroded soil in a series of experiments. The results show that the proposed S-growth curve model can be used to estimate the growth of the soil erosion area (average relative error 3%–9.7%) according to variable soil material and rainfall intensity. The original S-growth curve model can calculate the erosion areas of just one soil material and one rainfall condition whose average relative error is 7.5%–12.2%; compared to the simple time series analysis-moving average method (average relative error 5.7%–12.1%), our proposed S-growth curve model can reveal the physical mechanism and evolution of the research object.
Case Study of Particle Number Fluxes and Size Distributions during Nucleation Events in Southeastern Italy in the Summer
Authors: Conte Marianna , Donateo Antonio , Dinoi Adelaide , Belosi Franco , Contini Daniele
Published: July 2015

Concentrations, size distributions and particle number vertical turbulent fluxes were measured by the eddy-covariance method at an urban background site in southeastern Italy during the summer. CO2/H2O concentrations and fluxes were also determined together with meteorological parameters. Time series show that particles could be divided into two size classes with negatively-correlated temporal trends in diurnal hours: nanoparticles (diameter Dp < 50 nm) and larger particles (Dp > 50 nm). Larger particles include part of the Aitken mode and the accumulation mode. Nanoparticles peaked in diurnal hours due to the presence of several days with nucleation events when particles Dp > 50 nm were at minimum concentrations. Nucleation increased diurnal total particle concentration by a factor of 2.5, reducing mean and median diameters from Dmean = 62.3 ± 1.2 nm and Dmedian = 29.1 ± 1.3 nm on non-event days to Dmean = 35.4 ± 0.6 nm and Dmedian = 15.5 ± 0.3 nm on event days. During nucleation events, particle deposition increased markedly (i.e., downward fluxes), but no significant changes in CO2 concentrations and fluxes were observed. This is compatible with new particle formation above the measurement height and a consequent net transport towards the surface. Correlation with meteorology shows that the formation of new particles is correlated with solar radiation and favored at high wind velocity.
Characterization of Anion Exchange Membrane Containing Epoxy Ring and C–Cl Bond Quaternized by Various Amine Groups for Application in Fuel Cells
Authors: Jeong Sung , Lee Ju , Woo Sahng , Seo Jin , Min Byoung
Published: July 2015

Anion exchange membranes were synthesized from different compositions of glycidyl methacrylate (GMA) and vinylbenzyl chloride (VBC), with constant content of divinyl benzene (DVB) by radical polymerization using benzoyl peroxide (BPO) on non-woven polyethylene terephthalate (PET) substrate. Polymerized membranes were then quaternized by soaking in trimethylamine (TMA), triethylamine (TEA), tripropylamine (TPA), and 1,4-diazabicyclo [2.2.2] octane (DABCO). Characteristics of membranes were confirmed by Fourier transform infrared spectroscopy, water uptake, ion exchange capacity, ion conductivity, thermal, and alkaline stability. The results revealed that membranes quaternized by TPA and DABCO showed high affinity when GMA content was 15 wt% and 75 wt%, respectively. IEC and ion conductivity of membranes quaternized by TPA were 1.34 meq·g−1 and 0.022 S·cm−1 (at 60 °C), respectively. IEC and ion conductivity of membranes were quaternized by DABCO were 1.34 meq·g−1 and 0.021 S·cm−1 (at 60 °C), respectively. The results indicate that the membrane containing GMA 15 wt% quaternized by TPA showed the highest thermal stability among membranes and exhibited high ion conductivity compared to existing researches using GMA, VBC, and DVB monomers.
A Supply-Chain Analysis Framework for Assessing Densified Biomass Solid Fuel Utilization Policies in China
Authors: Wang Wenyan , Ouyang Wei , Hao Fanghua
Published: July 2015

Densified Biomass Solid Fuel (DBSF) is a typical solid form of biomass, using agricultural and forestry residues as raw materials. DBSF utilization is considered to be an alternative to fossil energy, like coal in China, associated with a reduction of environmental pollution. China has abundant biomass resources and is suitable to develop DBSF. Until now, a number of policies aimed at fostering DBSF industry have been proliferated by policy makers in China. However, considering the seasonality and instability of biomass resources, these inefficiencies could trigger future scarcities of biomass feedstocks, baffling the resilience of biomass supply chains. Therefore, this review paper focuses on DBSF policies and strategies in China, based on the supply chain framework. We analyzed the current developing situation of DBSF industry in China and developed a framework for policy instruments based on the supply chain steps, which can be used to identify and assess the deficiencies of current DBSF industry policies, and we proposed some suggestions. These findings may inform policy development and identify synergies at different steps in the supply chain to enhance the development of DBSF industry.
Speciation and Degrees of Contamination of Metals in Sediments from Upstream and Downstream Reaches along the Catchment of the Southern Bohai Sea, China
Authors: Xu Li , Li Jing
Published: July 2015

Environmental processes and biological community structures change along fluvial gradients within coastal river basins; the accumulation and associated risk of metal contamination would also be expected to change from upstream to downstream reaches. Speciation and degrees of contamination of metals in sediments from the upstream and downstream of river catchments of the southern Bohai Sea were investigated. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from upstream reaches were 82.6, 157, 63.6, 26.6, 0.18 and 24.9 mg/kg, respectively. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from downstream reaches were 38.0, 66.0, 38.9, 18.1, 0.16 and 24.0 mg/kg, respectively. Most of the Cu, Zn, Cr, Ni and Pb in sediments from both the upstream and downstream reaches was mainly associated with the residual fraction. However, Cd was preferentially bound to the exchangeable phase. A cluster analysis was used to study the degree of association between sites, and three distinct clusters were identified in both upstream and downstream sediments. A correlation analysis was conducted to determine the extent of association among metals and showed that metals in sediments from the upstream reaches have more affinity than those in the downstream area. Sediment quality guidelines were used to evaluate potential risks. The risks from Zn, Cr and Ni in the upstream reaches were higher than those from downstream reaches; however, the other three metals (Cu, Pb and Cd) showed opposite results.
Moving to Serene Nature May Prevent Poor Mental Health—Results from a Swedish Longitudinal Cohort Study
Authors: Van den Bosch Matilda , Östergren Per-Olof , Grahn Patrik , Skärbäck Erik , Währborg Peter
Published: July 2015

Green spaces are recognized for improving mental health, but what particular kind of nature is required is yet not elucidated. This study explores the effect of specific types of recreational nature qualities on mental health. Longitudinal data (1999/2000 and 2005) from a public health survey was distributed to a stratified sample (n = 24,945) of a Swedish population. People from rural or suburban areas (n = 9230) who had moved between baseline and follow-up (n = 1419) were studied. Individual geographic residence codes were linked to five predefined nature qualities, classified in geographic information systems (GIS). Any change in the amount of or type of qualities within 300 m distance between baseline and follow-up was correlated to any change in mental health (as measured by the General Health Questionnaire) by logistic regression models. On average, the population had limited access to nature qualities both pre- and post-move. There was no significant correlation between change in the amount of qualities and change in mental health. However, the specific quality “serene” was a significant determinant with a significantly decreased risk for women of change to mental ill-health at follow-up. The objective definition of the potentially health-promoting quality may facilitate implication in landscape practice and healthy planning.
Matrix Metalloproteinase 9 Gene Promoter (rs 3918242) Mutation Reduces the Risk of Diabetic Microvascular Complications
Authors: Zhang Zhongwen , Wu Xiaoyun , Cai Tian , Gao Weiyi , Zhou Xiaojun , Zhao Junyu , Yao Jinming , Shang Hongxia , Dong Jianjun , Liao Lin
Published: July 2015

Background: Many studies have evaluated the association between matrix metalloproteinase 9 (MMP9) gene promoter polymorphism and diabetic microvascular complications. However, the results are conflicting and inconclusive. The aim of this meta-analysis was to evaluate the association more precisely. Materials and Methods: Studies were retrieved from the PubMed, Embase, Medline, China National Knowledge Infrastructure, Web of Science, and Cochrane databases. All statistical analyses were performed using Review Manager 5.2. Results: Data were abstracted from four case-control studies that included 446 patients with diabetic microvascular complications and 496 diabetic control subjects. The MMP9-1562 C/T genotype was significantly associated with the risk of diabetic nephropathy after stratification by specific type of microvascular complication (CT + TT vs. CC: OR = 0.42, 95% CI = 0.26–0.69, p = 0.0006; TT vs. CC + CT: OR = 0.37, 95% CI = 0.19–0.76, p = 0.006). Conclusions: This study adds to the evidence that MMP9-1562 T gene mutation might reduce the risk of diabetic nephropathy.
Structural Diversity of Copper(II) Complexes with 9-Deazahypoxanthine and Their in Vitro SOD-Like Activity
Authors: Gáliková Jana , Trávníček Zdeněk
Published: July 2015

Two structurally different copper(II) complexes of the compositions [{Cu(9dhx)(H2O)3}2(µ-SO4)2] (1) and [Cu(9dhx)2(H2O)2(NO3)2]·H2O (2), involving 9-deazahypoxanthine (9dhx; 6-oxo-9-deazapurine; 9-deazahypoxanthine), have been prepared and characterized by elemental analysis, infrared and electronic spectroscopy, electrospray ionisation (ESI) mass spectrometry, thermogravimetric (TG) and differential thermal (DTA) analyses, and cyclic voltammetry. The X-ray structures of complexes 1 and [Cu(9dhx)2(H2O)2(NO3)2] (2a) revealed the distorted octahedral geometry in the vicinity of the copper(II) atoms, with the NO5 and N2O4 donor set, respectively. In the dimeric compound 1, the {Cu(9dhx)(H2O)3}2 units are bridged by sulfate groups with the Cu···Cu separation being 5.3446(2) Å. In both structures the 9dhx ligands are coordinated through the N3 atoms of the pyrimidine moieties. The SOD-like activity of complexes 1 and 2 was evaluated in vitro showing moderate effect, with the IC50 values equal to 18.20, and 53.33 μM, respectively.
Crystal Structure of a Hidden Protein, YcaC, a Putative Cysteine Hydrolase from Pseudomonas aeruginosa, with and without an Acrylamide Adduct
Authors: Grøftehauge Morten , Truan Daphne , Vasil Adriana , Denny Paul , Vasil Michael , Pohl Ehmke
Published: July 2015

As part of the ongoing effort to functionally and structurally characterize virulence factors in the opportunistic pathogen Pseudomonas aeruginosa, we determined the crystal structure of YcaC co-purified with the target protein at resolutions of 2.34 and 2.56 Å without a priori knowledge of the protein identity or experimental phases. The three-dimensional structure of YcaC adopts a well-known cysteine hydrolase fold with the putative active site residues conserved. The active site cysteine is covalently bound to propionamide in one crystal form, whereas the second form contains an S-mercaptocysteine. The precise biological function of YcaC is unknown; however, related prokaryotic proteins have functions in antibacterial resistance, siderophore production and NADH biosynthesis. Here, we show that YcaC is exceptionally well conserved across both bacterial and fungal species despite being non-ubiquitous. This suggests that whilst YcaC may not be part of an integral pathway, the function could confer a significant evolutionary advantage to microbial life.
Hydrogels for Engineering of Perfusable Vascular Networks
Authors: Liu Juan , Zheng Huaiyuan , Poh Patrina , Machens Hans-Günther , Schilling Arndt
Published: July 2015

Hydrogels are commonly used biomaterials for tissue engineering. With their high-water content, good biocompatibility and biodegradability they resemble the natural extracellular environment and have been widely used as scaffolds for 3D cell culture and studies of cell biology. The possible size of such hydrogel constructs with embedded cells is limited by the cellular demand for oxygen and nutrients. For the fabrication of large and complex tissue constructs, vascular structures become necessary within the hydrogels to supply the encapsulated cells. In this review, we discuss the types of hydrogels that are currently used for the fabrication of constructs with embedded vascular networks, the key properties of hydrogels needed for this purpose and current techniques to engineer perfusable vascular structures into these hydrogels. We then discuss directions for future research aimed at engineering of vascularized tissue for implantation.
Effect of rhBMP-2 Immobilized Anorganic Bovine Bone Matrix on Bone Regeneration
Authors: Huh Jung-Bo , Yang June-Jip , Choi Kyung-Hee , Bae Ji , Lee Jeong-Yeol , Kim Sung-Eun , Shin Sang-Wan
Published: July 2015

Anorganic bovine bone matrix (Bio-Oss®) has been used for a long time for bone graft regeneration, but has poor osteoinductive capability. The use of recombinant human bone morphogenetic protein-2 (rhBMP-2) has been suggested to overcome this limitation of Bio-Oss®. In the present study, heparin-mediated rhBMP-2 was combined with Bio-Oss® in animal experiments to investigate bone formation performance; heparin was used to control rhBMP-2 release. Two calvarial defects (8 mm diameter) were formed in a white rabbit model and then implanted or not (controls) with Bio-Oss® or BMP-2/Bio-Oss®. The Bio-Oss® and BMP-2/Bio-Oss® groups had significantly greater new bone areas (expressed as percentages of augmented areas) than the non-implanted controls at four and eight weeks after surgery, and the BMP-2/Bio-Oss® group (16.50 ± 2.87 (n = 6)) had significantly greater new bone areas than the Bio-Oss® group (9.43 ± 3.73 (n = 6)) at four weeks. These findings suggest that rhBMP-2 treated heparinized Bio-Oss® markedly enhances bone regeneration.
Vanadium(V)-Substitution Reactions of Wells–Dawson-Type Polyoxometalates: From [X2M18O62]6− (X = P, As; M = Mo, W) to [X2VM17O62]7−
Authors: Ueda Tadaharu , Nishimoto Yuriko , Saito Rie , Ohnishi Miho , Nambu Jun-ichi
Published: July 2015

The formation processes of V(V)-substituted polyoxometalates with the Wells–Dawson-type structure were studied by cyclic voltammetry and by 31P NMR and Raman spectroscopy. Generally, the vanadium-substituted heteropolytungstates, [P2VW17O62]7− and [As2VW17O62]7−, were prepared by mixing equimolar amounts of the corresponding lacunary species—[P2W17O61]10− and [As2W17O61]10−—and vanadate. According to the results of various measurements in the present study, the tungsten site in the framework of [P2W18O62]6− and [As2W18O62]6− without defect sites could be substituted with V(V) to form the [P2VW17O62]7− and [As2VW17O62]7−, respectively. The order in which the reagents were mixed was observed to be the key factor for the formation of Dawson-type V(V)-substituted polyoxometalates. Even when the concentration of each reagent was identical, the final products differed depending on the order of their addition to the reaction mixture. Unlike Wells–Dawson-type heteropolytungstates, the molybdenum sites in the framework of [P2Mo18O62]6− and [As2Mo18O62]6− were substituted with V(V), but formed Keggin-type [PVMo11O40]4− and [AsVMo11O40]4− instead of [P2VMo17O62]7− and [As2VMo17O62]7−, respectively, even though a variety of reaction conditions were used. The formation constant of the [PVMo11O40]4− and [AsVMo11O40]4− was hypothesized to be substantially greater than that of the [P2VMo17O62]7− and [As2VMo17O62]7−.
An Efficient Finite Element Framework to Assess Flexibility Performances of SMA Self-Expandable Carotid Artery Stents
Authors: Ferraro Mauro , Auricchio Ferdinando , Boatti Elisa , Scalet Giulia , Conti Michele , Morganti Simone , Reali Alessandro
Published: July 2015

Computer-based simulations are nowadays widely exploited for the prediction of the mechanical behavior of different biomedical devices. In this aspect, structural finite element analyses (FEA) are currently the preferred computational tool to evaluate the stent response under bending. This work aims at developing a computational framework based on linear and higher order FEA to evaluate the flexibility of self-expandable carotid artery stents. In particular, numerical simulations involving large deformations and inelastic shape memory alloy constitutive modeling are performed, and the results suggest that the employment of higher order FEA allows accurately representing the computational domain and getting a better approximation of the solution with a widely-reduced number of degrees of freedom with respect to linear FEA. Moreover, when buckling phenomena occur, higher order FEA presents a superior capability of reproducing the nonlinear local effects related to buckling phenomena.
In Vitro Analyses of the Toxicity, Immunological, and Gene Expression Effects of Cobalt-Chromium Alloy Wear Debris and Co Ions Derived from Metal-on-Metal Hip Implants
Authors: Posada Olga , Tate Rothwelle , Meek R.M. , Grant M.
Published: July 2015

Joint replacement has proven to be an extremely successful and cost-effective means of relieving arthritic pain and improving quality of life for recipients. Wear debris-induced osteolysis is, however, a major limitation and causes orthopaedic implant aseptic loosening, and various cell types including macrophages, monocytes, osteoblasts, and osteoclasts, are involved. During the last few years, there has been increasing concern about metal-on-metal (MoM) hip replacements regarding adverse reactions to metal debris associated with the MoM articulation. Even though MoM-bearing technology was initially aimed to extend the durability of hip replacements and to reduce the requirement for revision, they have been reported to release at least three times more cobalt and chromium ions than metal-on-polyethylene (MoP) hip replacements. As a result, the toxicity of metal particles and ions produced by bearing surfaces, both locally in the periprosthetic space and systemically, became a concern. Several investigations have been carried out to understand the mechanisms responsible for the adverse response to metal wear debris. This review aims at summarising in vitro analyses of the toxicity, immunological, and gene expression effects of cobalt ions and wear debris derived from MoM hip implants.
Poly(Dopamine)-Assisted Immobilization of Xu Duan on 3D Printed Poly(Lactic Acid) Scaffolds to Up-Regulate Osteogenic and Angiogenic Markers of Bone Marrow Stem Cells
Authors: Yeh Chia-Hung , Chen Yi-Wen , Shie Ming-You , Fang Hsin-Yuan
Published: July 2015

Three-dimensional printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating and Xu Duan (XD) immobilization to regulate cell adhesion, proliferation and differentiation of human bone-marrow mesenchymal stem cells (hBMSCs). We prepared PLA scaffolds and coated with polydopamine (PDA). The chemical composition and surface properties of PLA/PDA/XD were characterized by XPS. PLA/PDA/XD controlled hBMSCs’ responses in several ways. Firstly, adhesion and proliferation of hBMSCs cultured on PLA/PDA/XD were significantly enhanced relative to those on PLA. In addition, the focal adhesion kinase (FAK) expression of cells was increased and promoted cell attachment depended on the XD content. In osteogenesis assay, the osteogenesis markers of hBMSCs cultured on PLA/PDA/XD were significantly higher than seen in those cultured on a pure PLA/PDA scaffolds. Moreover, hBMSCs cultured on PLA/PDA/XD showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hBMSCs.
Distribution of Marine Lipophilic Toxins in Shellfish Products Collected from the Chinese Market
Authors: Wu Haiyan , Yao Jianhua , Guo Mengmeng , Tan Zhijun , Zhou Deqing , Zhai Yuxiu
Published: July 2015

To investigate the prevalence of lipophilic marine biotoxins in shellfish from the Chinese market, we used hydrophilic interaction liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure levels of okadaic acid (OA), azaspiracid (AZA1), pectenotoxin (PTX2), gymnodimine (GYM), and spirolide (SPX1). We collected and analyzed 291 shellfish samples from main production sites along a wide latitudinal transect along the Chinese coastline from December 2008 to December 2009. Results revealed a patchy distribution of the five toxins and highlighted the specific geographical distribution and seasonal and species variation of the putative toxigenic organisms. All five lipophilic marine biotoxins were found in shellfish samples. The highest concentrations of OA, AZA1, PTX2, GYM, and SPX1 were 37.3, 5.90, 16.4, 14.4, and 8.97 μg/kg, respectively. These values were much lower than the legislation limits for lipophilic shellfish toxins. However, the value might be significantly underestimated for the limited detection toxins. Also, these toxins were found in most coastal areas of China and were present in almost all seasons of the year. Thus, these five toxins represent a potential threat to human health. Consequently, studies should be conducted and measures should be taken to ensure the safety of the harvested product.
New Scalarane Sesterterpenoids from the Formosan Sponge Ircinia felix
Authors: Lai Ya-Yuan , Lu Mei-Chin , Wang Li-Hsueh , Chen Jih-Jung , Fang Lee-Shing , Wu Yang-Chang , Sung Ping-Jyun
Published: July 2015

Five new scalarane sesterterpenoids, felixins A–E (1–5), were isolated from the Formosan sponge Ircinia felix. The structures of scalaranes 1–5 were elucidated on the basis of spectroscopic analysis. Cytotoxicity of scalaranes 1–5 against the proliferation of a limited panel of tumor cell lines was evaluated.
Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin
Authors: Zhang Li , Wang Handong
Published: July 2015

Astaxanthin (ATX) is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA) as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma (PPARγ). Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX.
New α-Glucosidase Inhibitory Triterpenic Acid from Marine Macro Green Alga Codium dwarkense Boergs
Authors: Ali Liaqat , Khan Abdul , Al-Kharusi Lubna , Hussain Javid , Al-Harrasi Ahmed
Published: July 2015

The marine ecosystem has been a key resource for secondary metabolites with promising biological roles. In the current study, bioassay-guided phytochemical investigations were carried out to assess the presence of enzyme inhibitory chemical constituents from the methanolic extract of marine green alga—Codium dwarkense. The bioactive fractions were further subjected to chromatographic separations, which resulted in the isolation of a new triterpenic acid; dwarkenoic acid (1) and the known sterols; androst-5-en-3β-ol (2), stigmasta-5,25-dien-3β,7α-diol (3), ergosta-5,25-dien-3β-ol (4), 7-hydroxystigmasta-4,25-dien-3-one-7-O-β-d-fucopyranoside (5), 7-hydroxystigmasta-4,25-dien-3-one (6), and stigmasta-5,25-dien-3β-ol (7). The structure elucidation of the new compound was carried out by combined mass spectrometry and 1D (1H and 13C) and 2D (HSQC, HMBC, COSY, and NOESY) NMR spectroscopic data. The sub-fractions and pure constituents were assayed for enzymatic inhibition of alpha-glucosidase. Compound 1 showed significant inhibition at all concentrations. Compounds 2, 3, 5, and 7 exhibited a dose-dependent response, whereas compounds 4–6 showed moderate inhibition. Utilizing such marine-derived biological resources could lead to drug discoveries related to anti-diabetics.
Microintaglio Printing for Soft Lithography-Based in Situ Microarrays
Authors: Biyani Manish , Ichiki Takanori
Published: July 2015

Advances in lithographic approaches to fabricating bio-microarrays have been extensively explored over the last two decades. However, the need for pattern flexibility, a high density, a high resolution, affordability and on-demand fabrication is promoting the development of unconventional routes for microarray fabrication. This review highlights the development and uses of a new molecular lithography approach, called “microintaglio printing technology”, for large-scale bio-microarray fabrication using a microreactor array (µRA)-based chip consisting of uniformly-arranged, femtoliter-size µRA molds. In this method, a single-molecule-amplified DNA microarray pattern is self-assembled onto a µRA mold and subsequently converted into a messenger RNA or protein microarray pattern by simultaneously producing and transferring (immobilizing) a messenger RNA or a protein from a µRA mold to a glass surface. Microintaglio printing allows the self-assembly and patterning of in situ-synthesized biomolecules into high-density (kilo-giga-density), ordered arrays on a chip surface with µm-order precision. This holistic aim, which is difficult to achieve using conventional printing and microarray approaches, is expected to revolutionize and reshape proteomics. This review is not written comprehensively, but rather substantively, highlighting the versatility of microintaglio printing for developing a prerequisite platform for microarray technology for the postgenomic era.