bluuebunny/crossref_metadata_2025 huggingface dataset:
The 2-Hilbert space of a prequantum bundle gerbe
Authors: Bunk Severin , Sämann Christian , Szabo Richard J.
Published: October 2017

We construct a prequantum 2-Hilbert space for any line bundle gerbe whose Dixmier–Douady class is torsion. Analogously to usual prequantization, this 2-Hilbert space has the category of sections of the line bundle gerbe as its underlying 2-vector space. These sections are obtained as certain morphism categories in Waldorf’s version of the 2-category of line bundle gerbes. We show that these morphism categories carry a monoidal structure under which they are semisimple and abelian. We introduce a dual functor on the sections, which yields a closed structure on the morphisms between bundle gerbes and turns the category of sections into a 2-Hilbert space. We discuss how these 2-Hilbert spaces fit various expectations from higher prequantization. We then extend the transgression functor to the full 2-category of bundle gerbes and demonstrate its compatibility with the additional structures introduced. We discuss various aspects of Kostant–Souriau prequantization in this setting, including its dimensional reduction to ordinary prequantization.
Nonsingular localized wave solutions for the nonlocal Davey–Stewartson I equation with zero background
Authors: Xu Tao , Li Min , Huang Yehui , Chen Yang , Yu Chen
Published: October 2017

In this paper, via the elementary Darboux transformation, we study the nonsingular localized wave solutions of the partially parity-time [Formula: see text] symmetric nonlocal Davey–Stewartson I equation with zero background. In addition to the common dromion and line-soliton solutions, we obtain some new localized wave solutions including the periodical-soliton, quasi-line-soliton and defected-line-soliton solutions. Meanwhile, we give the exact nonsingular parametric conditions for the derived solutions to display different localized wave structures. In addition, we discuss the dynamical behavior of the obtained nonlinear localized wave solutions with graphical illustration.
Low-temperature sintered Li2(MnxTi1−x)O3microwave dielectric ceramics with adjustable τf
Authors: Liu Cheng , Zhang Huaiwu , Su Hua , Li Jie , Liao Yulong , Jia Lijun , Li Yuanxun
Published: October 2017

B2O3–Bi2O3–SiO2–ZnO (BBSZ) glass-modified Li2(Mn[Formula: see text]Ti[Formula: see text])O3ceramics were fabricated via a solid-state reaction route. Pure phase and dense crystal morphology were obtained at 900[Formula: see text]C. Suitable amount of Mn[Formula: see text]-ion substitution could adjust the [Formula: see text] value of the Li2(Mn[Formula: see text]Ti[Formula: see text])O3system to near zero. Among all of the Li2(Mn[Formula: see text]Ti[Formula: see text])O3samples, the sample with x = 0.9 (marked as BL9 in this paper) possessed good microwave dielectric properties: [Formula: see text] = 18, Q × f = 14,056 GHz (9.58 GHz) and [Formula: see text] = (+)2.43 ppm/[Formula: see text]C. It is suggested that the Li2(Mn[Formula: see text]Ti[Formula: see text])O3ceramic with BBSZ glass is a suitable low-temperature co-fired ceramic (LTCC) candidate for microwave applications.
Repair Methods of Complex Holes in a Three-Dimensional Model Based on Variation Level Set
Authors: Zhang Jing , Zhou Mingquan
Published: October 2017

With regard to the numerous complex holes that accompany a three-dimensional (3D) model reconstruction, a hole-repair method is proposed in this paper. First, signed distance function (SDF) is constructed, and the curved surface where the hole is positioned is expressed by a static SDF. Another dynamic SDF is used to express the initial curved surface. Using a variation level set on implicit surfaces, we introduce a global convex optimization energy model to perform minimum inducement, thus turning the problem of extracting the hole edge into a problem of spherical evolution of a hidden surface. Finally, we consider the extracted hole-edge surface as the initial observation surface and complete the hole repair using convolution and synthesis. The experiment shows that this algorithm can effectively restore notable geometrical features of areas with complex holes and can repair the holes in a model with many grids.
UAV Path Planning Based on Particle Swarm Optimization with Global Best Path Competition
Authors: Huang Chen , Fei Jiyou
Published: October 2017

Path planning is the essential aspect of autonomous flight system for unmanned aerial vehicles (UAVs). An improved particle swarm optimization (PSO) algorithm, named GBPSO, is proposed to enhance the performance of three-dimensional path planning for fixed-wing UAVs in this paper. In order to improve the convergence speed and the search ability of the particles, the competition strategy is introduced into the standard PSO to optimize the global best solution during the process of particle evolution. More specifically, according to a set of segment evaluation functions, the optimal path found by single waypoint selection way is adopted as one of the candidate global best paths. Meanwhile, based on the particle as an integrated individual, an optimal trajectory from the start point to the flight target is generated as another global best candidate path. Subsequently, the global best path is determined by considering the pre-specified elevation function values of two candidate paths. Finally, to verify the performance of the proposed method, GBPSO is compared with some existing path-planning methods in two simulation scenarios with different obstacles. The results demonstrate that GBPSO is more effective, robust and feasible for UAV path planning.
A Multiagent Planning Approach for Cooperative Patrolling with Non-Stationary Adversaries
Authors: Beynier Aurélie
Published: October 2017

Multiagent patrolling is the problem faced by a set of agents that have to visit a set of sites to prevent or detect some threats or illegal actions. Although it is commonly assumed that patrollers share a common objective, the issue of cooperation between the patrollers has received little attention. Over the last years, the focus has been put on patrolling strategies to prevent a one-shot attack from an adversary. This adversary is usually assumed to be fully rational and to have full observability of the system. Most approaches are then based on game theory and consists in computing a best response strategy. Nonetheless, when patrolling frontiers, detecting illegal fishing or poaching; patrollers face multiple adversaries with limited observability and rationality. Moreover, adversaries can perform multiple illegal actions over time and space and may change their strategies as time passes. In this paper, we propose a multiagent planning approach that enables effective cooperation between a team of patrollers in uncertain environments. Patrolling agents are assumed to have partial observability of the system. Our approach allows the patrollers to learn a generic and stochastic model of the adversaries based on the history of observations. A wide variety of adversaries can thus be considered with strategies ranging from random behaviors to fully rational and informed behaviors. We show that the multiagent planning problem can be formalized by a non-stationary DEC- POMDP. In order to deal with the non-stationary, we introduce the notion of context. We then describe an evolutionary algorithm to compute patrolling strategies on-line, and we propose methods to improve the patrollers’ performance.
Automatic Creation of Machine Learning Workflows with Strongly Typed Genetic Programming
Authors: Křen Tomáš , Pilát Martin , Neruda Roman
Published: October 2017

Manual creation of machine learning ensembles is a hard and tedious task which requires an expert and a lot of time. In this work we describe a new version of the GP-ML algorithm which uses genetic programming to create machine learning workows (combinations of preprocessing, classification, and ensembles) automatically, using strongly typed genetic programming and asynchronous evolution. The current version improves the way in which the individuals in the genetic programming are created and allows for much larger workows. Additionally, we added new machine learning methods. The algorithm is compared to the grid search of the base methods and to its previous versions on a set of problems from the UCI machine learning repository.
Grounding of HTN Planning Domain
Authors: Ramoul Abdeldjalil , Pellier Damien , Fiorino Humbert , Pesty Sylvie
Published: October 2017

Many Artificial Intelligence techniques have been developed for intelligent and autonomous systems to act and make rational decisions based on perceptions of the world state. Among these techniques, HTN (Hierarchical Task Network) planning is one of the most used in practice. HTN planning is based on expressive languages allowing to specify complex expert knowledge for real world domains. At the same time, many preprocessing techniques for classical planning were proposed to speed up the search. One of these technique, named grounding, consists in enumerating and instantiating all the possible actions from the planning problem descriptions. This technique has proven its effectiveness. Therefore, combining the expressiveness of HTN planning with the efficiency of the grounding preprocessing techniques used in classical planning is a very challenging issue. In this paper, we propose a generic algorithm to ground the domain representation for HTN planning. We show experimentally that grounding process improves the performances of state of the art HTN planners on a range of planning problems from the International Planning Competition (IPC).
Automated Domain Bias Correction and Its Application in Text-Based Personality Analysis
Authors: Yakut Kiliç Işil Doğa , Pan Shimei
Published: October 2017

Personality prediction based on textual data is one topic gaining attention recently for its potential in large-scale personalized applications such as social media-based marketing. However, when applying this technology in real-world applications, users often encounter situations in which the personality traits derived from different sources (e.g., social media posts versus emails) are inconsistent. Varying results for the same individual renders the technology ineffective and untrustworthy. In this paper, we demonstrate the impact of domain differences in automated text-based personality prediction. We also propose different approaches for domain error correction to meet different needs: (a) single or multi-domain correction and (b) outcome-based or input feature-based error correction. We conduct comprehensive experiments to evaluate the effectiveness of these methods. Our findings demonstrate a significant improvement of prediction accuracy with the proposed methods. (e.g., 20–30% relative error reduction using outcome-based error correction or 48% increase of F1 score using feature-based error correction).
BRIGHT LUMINESCENCE OF FIRE RETARDANT ALUMINUM HYDROXIDE-SILICA SPHERE COMPOSITE
Authors: KONG HA-SUNG , KIM BYOUNG-JU , KANG KWANG-SUN
Published: October 2017

Bright luminescence was achieved with excess amount of aluminum hydroxide with silica spheres. Various amounts of aluminum hydroxide were attached to silica spheres to improve the performance of fire retardancy. Although silica spheres attached with 60[Formula: see text]wt.% of AlCl3 (AlOH-A) showed no color change and luminescent chromophores, silica spheres attached with 80[Formula: see text]wt.% of (AlOH-B) and 100% of (AlOH-C) of AlCl3 changed the color and produced luminescent chromophores. The solution colors became intense yellow and brown for AlOH-B and AlOH-C, respectively, after 15 days. The FTIR spectra showed the characteristic absorption peaks of Al–OH and Si–O–Al. The concentration dependent photoluminescence (PL) intensities were continuously increased until 242[Formula: see text]mg addition of the colored solution and then slightly decreased thereafter for both AlOH-B and AlOH-C. The PL peaks shifted toward red by increasing the excitation wavelength for both AlOH-B and AlOH-C. Large Stoke shifts, such as 73 and 68[Formula: see text]nm for AlOH-B and AlOH-C, respectively, were observed.
AMORPHOUS VANADIUM DIOXIDE: THE RESIST FOR ELECTRON-BEAM LITHOGRAPHY
Authors: STEFANOVICH GENRIKH , VELICHKO ANDREY , PERGAMENT ALEXANDER , BORISKOV PETER
Published: October 2017

Amorphous vanadium dioxide, in combination with the resist properties, allowing one to create nanoscale structures, and with the effects of electrical switching and memory, should be in demand by the electronic industry. The opportunity to prepare highly sensitive to electron beam, optical and ion irradiation oxide films of vanadium by vacuum methods allows hope for simplified methods for coating and developing resists based on vanadium oxides. The scope of this review article is indicated by its title, namely, it encompasses the authors’ experimental results and model approximations on electron-beam modification of vanadium dioxide thin films and application of these films as inorganic nanolithography resists. These findings have been earlier published in a number of scattered original papers, and here we unite them all in one detailed review supplementing with new, previously unpublished data.
Strong Lp convergence of wavelet deconvolution density estimators
Authors: Liu Youming , Zeng Xiaochen
Published: October 2017

Using compactly supported wavelets, Giné and Nickl [Uniform limit theorems for wavelet density estimators, Ann. Probab. 37(4) (2009) 1605–1646] obtain the optimal strong [Formula: see text] convergence rates of wavelet estimators for a fixed noise-free density function. They also study the same problem by spline wavelets [Adaptive estimation of a distribution function and its density in sup-norm loss by wavelet and spline projections, Bernoulli 16(4) (2010) 1137–1163]. This paper considers the strong [Formula: see text] convergence of wavelet deconvolution density estimators. We first show the strong [Formula: see text] consistency of our wavelet estimator, when the Fourier transform of the noise density has no zeros. Then strong [Formula: see text] convergence rates are provided, when the noises are severely and moderately ill-posed. In particular, for moderately ill-posed noises and [Formula: see text], our convergence rate is close to Giné and Nickl’s.
Analysis of Linear and Nonlinear Optical Properties of NiO Nanoparticles by Sol–Gel Method
Authors: Usha V. , Vettumperumal R. , Kalyanaraman S. , Thangavel R.
Published: October 2017

Nanocrystalline nickel oxide (NiO) were prepared by low cost sol–gel method and analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectra (EDX), Raman, photoluminescence (PL) and UV-Vis-NIR spectroscopic techniques. XRD spectrum confirmed the face centered cubic structure of NiO nanoparticles and it showed polycrystalline nature without any impurity. Magnetic ordered phase related modes of NiO nanoparticles was observed from Raman spectra, which also confirmed the absence of secondary phases in NiO nanoparticles. Linear and nonlinear refractive index and optical susceptibility of NiO nanoparticles were calculated and discussed using Tauc’s method and Wemple and DiDomenico single oscillator model. Calculated maximum value of third ordered nonlinear optical susceptibility ([Formula: see text] is [Formula: see text] revealed that the NiO nanoparticles were suitable in nonlinear optical devices applications. Simulation of second harmonic efficiency, spectral band width and quasi phase matching of NiO nanocrystals are discussed using optiFDTD.
Acoustics and Transport Properties of PEG Blended with CuO Nanoparticles: A Novel Application to Heat Transfer
Authors: Kamila Susmita , Venu Gopal V. R. , Satish B. M.
Published: October 2017

The present investigation reports the acoustics and transport properties of a series of colloidal dispersion of nanocopper oxide in polyethylene glycol (PEG-400). The data are presented for five different CuO nanofluids of varying concentration in PEG prepared by the ultrasonication technique. The synthesized powder samples were characterized for their sizes and arrangement by X-ray Diffraction analysis (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), which shows the particulate size to be of nanoscale with elongated shape. Similarly, the size and stability of nanofluids were studied by zeta potential and particle size analysis. Besides, ultrasonic velocity, viscosity measurement show better dispersivity of nanoparticles and molecular environment of the nanofluids, whereas the enhanced thermal as well as electrical conductivities of nanofluids can make them suitable for use as heat transfer fluids.
Wavelet estimation of functional coefficient regression models
Authors: Montoril Michel H. , Morettin Pedro A. , Chiann Chang
Published: October 2017

The area of nonlinear time series models has experienced a great development since the 1980s. Although there is a wide range of parametric nonlinear time series models, in general, we do not know if the postulated model is the most appropriated one for a specific data set. This situation highlights the importance of nonparametric models. An interesting nonparametric model to fit nonlinear time series is the well-known functional coefficient regression model. Nonparametric estimations by, e.g., local linear regression and splines, are developed in the literature. In this work, we study the estimation of such a model using wavelets. It is a proposal that takes into account both, classical and warped wavelets. We present the rates of convergence of the proposed estimators and carry out simulation studies to evaluate automatic procedures (among AIC, AICc and BIC) for selecting the coarsest and finest levels to be used during the estimation process. Moreover, we illustrate the methodology with an application to a real data set, where we also calculate multi-step-ahead forecasts and compare the results with other methods known in the literature.
Evaluating the quality of SHAPE data simulated by k-mers for RNA structure prediction
Authors: Montaseri Soheila , Zare-Mirakabad Fatemeh , Ganjtabesh Mohammad
Published: October 2017

Finding an effective measure to predict a more accurate RNA secondary structure is a challenging problem. In the last decade, an experimental method, known as selective [Formula: see text]-hydroxyl acylation analyzed by primer extension (SHAPE), was proposed to measure the tendency of forming a base pair for almost all nucleotides in an RNA sequence. These SHAPE reactivities are then utilized to improve the accuracy of RNA structure prediction. Due to a significant impact of SHAPE reactivity and in order to reduce the experimental costs, we propose a new model called HL-k-mer. This model simulates the SHAPE reactivity for each nucleotide in an RNA sequence. This is done by fetching the SHAPE reactivities for all sub-sequences of length k (k-mers) appearing in helix and loop regions. For evaluating the quality of simulated SHAPE data, ESD-Fold method is used based on the SHAPE data simulated by the HL-k-mer model ([Formula: see text]). Also, for further evaluation of simulated SHAPE data, three different methods are employed. We also extend this model to simulate the SHAPE data for the RNA pseudoknotted structure. The results indicate that the average accuracies of prediction using the SHAPE data simulated by our models (for [Formula: see text]) are higher compared to the experimental SHAPE data.
BIonic system: Extraction of Lovelock gravity from a Born–Infeld-type theory
Authors: Naimi Yaghoob , Sepehri Alireza , Ghaffary Tooraj , Ghaforyan Hossein , Ebrahimzadeh Majid
Published: October 2017

It was shown that both Lovelock gravity and Born–Infeld (BI) electrodynamics can be obtained from low effective limit of string theory. Motivated by the mentioned unique origin of the gauge-gravity theories, we are going to find a close relation between them. In this research, we start from the Lagrangian of a BI-type nonlinear electrodynamics with an exponential form to extract the action of Lovelock gravity. We investigate the origin of Lovelock gravity in a system of branes which are connected with each other by different wormholes through a BIonic system. These wormholes are produced as due to the nonlinear electrodynamics which are emerged on the interacting branes. By approaching branes, wormholes dissolve into branes and Lovelock gravity is generated. Also, throats of some wormholes become smaller than their horizons and they transit to black holes. Generalizing calculations to M-theory, it is found that by compacting Mp-branes, Lovelock gravity changes to nonlinear electrodynamics and thus both of them have the same origin. This result is consistent with the prediction of BIonic model in string theory.
The Pattern of China’s Financial Initiative in Latin America: A Comparative Study
Authors: TENG CHUNG-CHIAN
Published: October 2017

Since the start of the 21st century, it is clear that China has increasingly turned its attention to Latin America. Although not included in China’s “One Belt, One Road” initiative officially, Latin America has already garnered substantial commitment from China as a result of the latter’s financial funding for development projects and the enhancement of two-way trade relations.

In recent years, scholarly research has tended to analyze China’s financial clout and its impact on the governmental domestic and external decisions of Latin American countries. In this study, my purpose is to examine China’s financial initiative and its influence on development projects in Latin America.

With the advent of a “new normal” in China, Xi Jinping and Li Keqiang respectively proposed a “[Formula: see text]” model and “[Formula: see text]” model in 2014 and 2015 — a reflection of China’s assertive economic diplomacy during the Xi era. Their plan was to have China adopt a more active position toward the provision of financial loans to Latin American nations.

China’s financial funds and construction assistance have been poured into key infrastructural projects, such as those related to power generation and transportation in Ecuador and Argentina. It can be expected that such projects satisfy the needs of both the people as well as the government, and contribute to genuine development there. On top of the involvement of China in relation to technology, equipment, and design, an expansion in cooperation and partnership is currently and will also be in the future the best reward for China.
Dedekind sums take each value infinitely many times
Authors: Girstmair Kurt
Published: October 2017

For [Formula: see text] and [Formula: see text], [Formula: see text], let [Formula: see text] denote the classical Dedekind sum. We show that Dedekind sums take this value infinitely many times in the following sense. There are pairs [Formula: see text], [Formula: see text], with [Formula: see text] tending to infinity as [Formula: see text] grows, such that [Formula: see text] for all [Formula: see text].
Square-full primitive roots
Authors: Munsch Marc , Trudgian Tim
Published: October 2017

We use character sum estimates to give some bounds on the least square-full primitive root modulo a prime. In particular, we show that there is a square-full primitive root mod [Formula: see text] less than [Formula: see text].
Central binomial coefficients divisible by or coprime to their indices
Authors: Sanna Carlo
Published: October 2017

Let [Formula: see text] be the set of all positive integers [Formula: see text] such that [Formula: see text] divides the central binomial coefficient [Formula: see text]. Pomerance proved that the upper density of [Formula: see text] is at most [Formula: see text]. We improve this bound to [Formula: see text]. Moreover, let [Formula: see text] be the set of all positive integers [Formula: see text] such that [Formula: see text] and [Formula: see text] are relatively prime. We show that [Formula: see text] for all [Formula: see text].
Global attractivity of the predator–prey system for cotton aphid and seven-spot ladybird beetle with stage structure
Authors: Zheng Lifei , Hu Guixin , Zhao Huiyan , Piyaratne M. K. D. K. , Wan Aying
Published: October 2017

It is well known that the cotton aphid is the major pest in cotton fields of Northwest China, and seven-spot ladybird is an important natural enemy among the various possible natural enemies of cotton aphid. In order to increase the applications of population dynamics in integrated pest management and control the cotton aphids biologically, we need to understand the population dynamics of cotton aphid and their natural enemies. A delay predator–prey system on cotton aphid and seven-spot ladybird beetle are proposed in this paper. Based on the comparison theorem and an iterative method, we investigate the global attractivity of the equilibrium points which have important biological meanings. Furthermore, some numerical simulations were carried out to illustrate and expand our theoretical results, in which a conjecture to generalize the well-known Theorem 16.4 in H. R. Thiemes book was put forward, which was taken as the open problem. The numerical simulations show coexistence of periodic solution, confirming the theoretical prediction.
Analysis of the characteristics of thick-film NTC thermistor devices manufactured by screen-printing and firing technique and by room temperature aerosol deposition method (ADM)
Authors: Schubert Michaela , Kita Jaroslaw , Münch Christian , Moos Ralf
Published: October 2017

The study compares thick-film NTC thermistor devices, produced by the screen-printing (and firing) technique and by the Aerosol Deposition Method (ADM) at room temperature. The devices are compared with respect to film quality (optical, mechanical) and to the negative temperature coefficient of resistance (NTCR) parameters [Formula: see text] and [Formula: see text]. While the screen-printed films are porous, the Aerosol Deposited (AD) films are characterized by high tightness, mechanical stability, and a production at room temperature. The electrical analysis shows that the AD films reach the [Formula: see text]- and [Formula: see text]-values of bulk NTCRs from literature after a moderate tempering step below 400[Formula: see text]C in air. The screen-printed films show [Formula: see text]-values that are comparable to the values of bulk NTCRs from literature and [Formula: see text]-values that are significantly higher.
d-matching in k-uniform hypergraphs
Authors: Zhang Yi , Lu Mei
Published: October 2017

A matching of a [Formula: see text]-uniform hypergraph is a set of pairwise disjoint edges. A [Formula: see text]-matching in a [Formula: see text]-uniform hypergraph [Formula: see text] is a matching of size [Formula: see text]. Let [Formula: see text] be a [Formula: see text]-uniform hypergraph of order [Formula: see text] and [Formula: see text]. If [Formula: see text] for any two adjacent vertices [Formula: see text], and [Formula: see text], then [Formula: see text] contains a [Formula: see text]-matching. This result is an extension of a work of Bollobás, Daykin and Erdős [Sets of independent edges of a hypergraph, Quart. J. Math. Oxford 21 (1976) 25–32].
Distinct roles of intracellular heat shock protein 70 in maintaining gastrointestinal homeostasis
Authors: Wang Yunwei , Lin Fanfei , Zhu Xiaorong , Leone Vanessa A. , Dalal Sushila , Tao Yun , Messer Jeannette S. , Chang Eugene B.
Published: October 2017

The inducible heat shock protein 70 (Hsp70) is both cytoprotective and immunomodulatory, potentially accounting for its critical role in maintaining gastrointestinal homeostasis. When levels are reduced in conditions like inflammatory bowel diseases (IBD), loss of function contributes to the severity and chronicity of these diseases, although through which cell types and mechanisms remains unclear. Here, the role of Hsp70-mediated intestinal epithelial protection and immune regulation in experimental colitis was examined by using a villin promoter-driven Hsp70 transgene in the 2,4,6-trinitrobenzene sulfonic acid (TNBS) and dextran sodium sulfate (DSS) models and in IL-10/Hsp70 double knockout (IL10−/−/Hsp70−/−) mice. In addition, Hsp70-mediated IL-10 production and immune protection were investigated using a CD45RBhigh transfer model and measuring colonic and immune cell cytokine expression during colitis. We found that the epithelial-specific expression of Hsp70 transgene attenuated DSS-induced colitis in Hsp70−/− mice by protecting tight junctions (TJ) and their interaction with the TJ-associated protein ZO-1. In the TNBS colitis and CD45RBhigh model, Hsp70 carried out its intracellular anti-inflammatory function by maintaining IL-10 production. Impaired ERK phosphorylation, but not p38 or JNK phosphorylation pathways, was associated with decreased IL-10 production in Hsp70-deficient cells. Together, these actions can be leveraged in the context of cellular specificity to develop complementary strategies that can lead to reduction in mucosal injury and immune activation in colonic colitis development.

NEW & NOTEWORTHY Using four different experimental colitis models, we filled an important gap in knowledge by defining essential roles of intracellular heat shock protein 70 in different cell types in maintaining intestinal integrity and immune regulation. These findings are relevant to human inflammatory bowel diseases and represent potential avenues for developing therapeutic strategies, not only to counter the destructive processes of inflammation but also to promote tissue healing and prevent complications frequently associated with chronic intestinal inflammation.
Rapid change of liver stiffness after variceal ligation and TIPS implantation
Authors: Piecha Felix , Paech Daniel , Sollors Janina , Seitz Helmut-Karl , Rössle Martin , Rausch Vanessa , Mueller Sebastian
Published: October 2017

Liver stiffness (LS) as measured by transient elastography is widely used to screen for liver fibrosis. However, LS also increases in response to pressure changes like congestion but no data on portal pressure are available. We study here the effect of rapid portal pressure changes on LS. Therefore, LS was assessed directly prior and after ligation of esophageal varices ( n = 11) as well as transjugular intrahepatic portosystemic shunt (TIPS) implantation in patients with established cirrhosis ( n = 14). Additionally, we retrospectively analyzed changes in LS and variceal size in patients with sequential gastroscopic monitoring and LS measurements ( n = 14). To study LS and portal pressure in healthy livers, LS (µFibroscan; Echosens, Paris, France) and invasive pressures (Powerlab, AD Instruments, New Zealand) were assessed in male Wistar rats after ligation of single liver lobes. Ligation of esophageal varices caused an immediate and significant increase of LS from 40.3 ± 19.0 to 56.1 ± 21.5 kPa. Likewise, LS decreased significantly from 53.1 ± 16.6 to 43.8 ± 17.3 kPa after TIPS placement, which correlated significantly with portal pressure ( r = 0.558). In the retrospective cohort, the significant LS decrease from 54.9 ± 23.5 to 47.9 ± 23.8 kPa over a mean observation interval of 4.3 ± 3 mo was significantly correlated with a concomitant increase of variceal size ( r = −0.605). In the animal model, LS and portal pressure increased significantly after single lobe ligation without changes of arterial or central venous pressure. In conclusion, rapid changes of portal pressure are a strong modulator of LS in healthy and cirrhotic organs. In patients with stable cirrhosis according to the model for end-stage liver disease (MELD), a decrease of LS may be indicative for enlarging varices.

NEW & NOTEWORTHY Liver stiffness (LS) immediately increases after variceal ligation while it decreases after transjugular intrahepatic portosystemic shunt (TIPS) implantation due to portal pressure changes. LS and portal pressure rapidly increase after single lobe ligation in Wistar rats without changes of arterial or central venous pressure. Collateral formation may be one cause for a transient decrease in LS in the absence of other confounders. Such pressure changes should be considered when interpreting LS in clinical practice.
Parenchymal strain heterogeneity during oscillatory ventilation: why two frequencies are better than one
Authors: Herrmann Jacob , Tawhai Merryn H. , Kaczka David W.
Published: October 2017

High-frequency oscillatory ventilation (HFOV) relies on low tidal volumes cycled at supraphysiological rates, producing fundamentally different mechanisms for gas transport and exchange compared with conventional mechanical ventilation. Despite the appeal of using low tidal volumes to mitigate the risks of ventilator-induced lung injury, HFOV has not improved mortality for most clinical indications. This may be due to nonuniform and frequency-dependent distribution of flow throughout the lung. The goal of this study was to compare parenchymal strain heterogeneity during eucapnic HFOV when using oscillatory waveforms that consisted of either a single discrete frequency or two simultaneous frequencies. We utilized a three-dimensional, anatomically structured canine lung model for simulating frequency-dependent ventilation distribution. Gas transport was simulated via direct alveolar ventilation, advective mixing at bifurcations, turbulent and oscillatory dispersion, and molecular diffusion. Volume amplitudes at each oscillatory frequency were iteratively optimized to attain eucapnia. Ventilation using single-frequency HFOV demonstrated increasing heterogeneity of acinar flow and CO2 elimination with frequency for frequencies greater than the resonant frequency. For certain pairs of frequencies, a linear combination of the two corresponding ventilation distributions yielded reduced acinar strain heterogeneity compared with either frequency alone. Our model demonstrates that superposition of two simultaneous oscillatory frequencies can achieve more uniform ventilation distribution, and therefore lessen the potential for ventilator-induced lung injury, compared with traditional single-frequency HFOV.

NEW & NOTEWORTHY In this study, we simulated oscillatory ventilation with multiple simultaneous frequencies using a computational lung model that includes distributed flow and gas transport. A mechanism of benefit was identified by which ventilation with two simultaneous frequencies results in reduced acinar strain heterogeneity compared with either frequency alone. This finding suggests the possibility of tuning the spectral content of ventilator waveforms according to patient-specific mechanical heterogeneity.
Occurrence of cardiac output decrease (via stroke volume) is more pronounced in women than in men during prolonged dry static apnea
Authors: Magnani Sara , Mulliri Gabriele , Sainas Gianmarco , Ghiani Giovanna , Pinna Virginia , Sanna Irene , Crisafulli Antonio , Tocco Filippo
Published: October 2017

Little is known about sex differences in autonomic cardiovascular regulation of the diving response, and the few available studies of these differences were conducted on subjects with limited or no diving experience. We examined the influence of sex on hemodynamics during dry static apnea (SA) in eight male and eight female elite divers matched for their breath hold (BH) ability. Hemodynamics was assessed by means of simultaneous echocardiography and impedance cardiography measurements, and arterial pressure and oxygen saturation ([Formula: see text]) were also collected. In the first quarter (AP25%) and half (AP50%) of apnea duration cardiac output (CO) showed a more rapid and intense decrease in women than in men (−43% vs. −17% during AP25% and −40% vs. −19% during AP50%, respectively, P < 0.05). At the same time points, systemic vascular resistance (SVR) increased more in women than in men (+22% vs. +100% at AP25% and +48% vs. +107% at AP50%, respectively, P < 0.05). [Formula: see text] progressively declined in both groups, but men showed a more pronounced decrease than women at the end of apneas (−13% vs. −5%, respectively, P < 0.05). In men the higher the body surface area values the longer the apnea, while in women the higher the SVR response the longer the apnea. In elite female divers, the magnitude of CO decrease during dry SA was larger than in male divers. The capacities to store oxygen and to reduce O2 consumption play a pivotal role in BH performance, but their extent seems to be different in the sexes.

NEW & NOTEWORTHY This is the first study in which the influence of sex on hemodynamics during dry static apnea has been investigated in two groups of elite divers matched for their breath hold ability. We also show the correlation between the performances obtained by divers during a real competition and their anthropometric, respiratory, and cardiovascular characteristics.
Phosphorylation of connexin 43 induced by traumatic brain injury promotes exosome release
Authors: Chen Wei , Guo Yijun , Yang Wenjin , Chen Lei , Ren Dabin , Wu Chenxing , He Bin , Zheng Ping , Tong Wusong
Published: October 2017

Traumatic brain injury (TBI) caused by the external force leads to the neuronal dysfunction and even death. TBI has been reported to significantly increase the phosphorylation of glial gap junction protein connexin 43 (Cx43), which in turn propagates damages into surrounding brain tissues. However, the neuroprotective and anti-apoptosis effects of glia-derived exosomes have also been implicated in recent studies. Therefore, we detected whether TBI-induced phosphorylation of Cx43 would promote exosome release in rat brain. To generate TBI model, adult male Sprague-Dawley rats were subjected to lateral fluid percussion injury. Phosphorylated Cx43 protein levels and exosome activities were quantified using Western blot analysis following TBI. Long-term potentiation (LTP) was also tested in rat hippocampal slices. TBI significantly increased the phosphorylated Cx43 and exosome markers expression in rat ipsilateral hippocampus, but not cortex. Blocking the activity of Cx43 or ERK, but not JNK, significantly suppressed TBI-induced exosome release in hippocampus. Furthermore, TBI significantly inhibited the induction of LTP in hippocampal slices, which could be partially but significantly restored by pretreatment with exosomes. The results imply that TBI-activated Cx43 could mediate a nociceptive effect by propagating the brain damages, as well as a neuroprotective effect by promoting exosome release.

NEW & NOTEWORTHY We have demonstrated in rat traumatic brain injury (TBI) models that both phosphorylated connexin 43 (p-Cx43) expression and exosome release were elevated in the hippocampus following TBI. The promoted exosome release depends on the phosphorylation of Cx43 and requires ERK signaling activation. Exosome treatment could partially restore the attenuated long-term potentiation. Our results provide new insight for future therapeutic direction on the functional recovery of TBI by promoting p-Cx43-dependent exosome release but limiting the gap junction-mediated bystander effect.
Effect of Glycine, Pyruvate, and Resveratrol on the Regeneration Process of Postischemic Intestinal Mucosa
Authors: Brencher Lisa , Petrat Frank , Stych Katrin , Hamburger Tim , Kirsch Michael
Published: October 2017

Background. Intestinal ischemia is often caused by a malperfusion of the upper mesenteric artery. Since the intestinal mucosa is one of the most rapidly proliferating organs in human body, this tissue can partly regenerate itself after the onset of ischemia and reperfusion (I/R). Therefore, we investigated whether glycine, sodium pyruvate, and resveratrol can either support or potentially harm regeneration when applied therapeutically after reperfusion injury. Methods. I/R of the small intestine was initiated by occluding and reopening the upper mesenteric artery in rats. After 60 min of ischemia and 300 min of reperfusion, glycine, sodium pyruvate, or resveratrol was administered intravenously. Small intestine regeneration was analyzed regarding tissue damage, activity of saccharase, and Ki-67 positive cells. Additionally, systemic parameters and metabolic ones were obtained at selected periods. Results. Resveratrol failed in improving the outcome after I/R, while glycine showed a partial beneficial effect. Sodium pyruvate ameliorated metabolic acidosis, diminished histopathologic tissue injury, and increased cell proliferation in the small intestine. Conclusion. While glycine could improve in part regeneration but not proliferation, sodium pyruvate seems to be a possible therapeutic agent to facilitate proliferation and to support mucosal regeneration after I/R injury to the small intestine.
Crosstalk between Substrates and Rho-Associated Kinase Inhibitors in Cryopreservation of Tissue-Engineered Constructs
Authors: Bit Arindam , Kumar Awanish , Singh Abhishek Kumar , Rizvanov Albert A. , Kiassov Andrey P. , Patra Pradeep Kumar , Kumar Munish , Bissoyi Akalabya
Published: October 2017

It is documented that human mesenchymal stem cells (hMSCs) can be differentiated into various types of cells to present a tool for tissue engineering and regenerative medicine. Thus, the preservation of stem cells is a crucial factor for their effective long-term storage that further facilitates their continuous supply and transportation for application in regenerative medicine. Cryopreservation is the most important, practicable, and the only established mechanism for long-term preservation of cells, tissues, and organs, and engineered tissues; thus, it is the key step for the improvement of tissue engineering. A significant portion of MSCs loses cellular viability while freeze-thawing, which represents an important technical limitation to achieving sufficient viable cell numbers for maximum efficacy. Several natural and synthetic materials are extensively used as substrates for tissue engineering constructs and cryopreservation because they promote cell attachment and proliferation. Rho-associated kinase (ROCK) inhibitors can improve the physiological function and postthaw viability of cryopreserved MSCs. This review proposes a crosstalk between substrate topology and interaction of cells with ROCK inhibitors. It is shown that incorporation of ionic nanoparticles in the presence of an external electrical field improves the generation of ROCK inhibitors to safeguard cellular viability for the enhanced cryopreservation of engineered tissues.
The Role of Insulin Receptor Isoforms in Diabetes and Its Metabolic and Vascular Complications
Authors: Escribano O. , Beneit N. , Rubio-Longás C. , López-Pastor A. R. , Gómez-Hernández A.
Published: October 2017

The insulin receptor (IR) presents by alternative splicing two isoforms: IRA and IRB. The differential physiological and pathological role of both isoforms is not completely known, and it is determinant the different binding affinity for insulin-like growth factor. IRB is more abundant in adult tissues and it exerts mainly the metabolic actions of insulin, whereas IRA is mainly expressed in fetal and prenatal period and exerts mitogenic actions. However, the change in the expression profile of both IR isoforms and its dysregulation are associated with the development of different pathologies, such as cancer, insulin resistance, diabetes, obesity, and atherosclerosis. In some of them, there is a significant increase of IRA/IRB ratio conferring a proliferative and migratory advantage to different cell types and favouring IGF-II actions with a sustained detriment in the metabolic effects of insulin. This review discussed specifically the role of IR isoforms as well as IGF-IR in diabetes and its associated complications as obesity and atherosclerosis. Future research with new IR modulators might be considered as possible targets to improve the treatment of diabetes and its associated complications.
Design and Evaluation of a Mathematical Optimization Model for Traffic Signal Plan Transition Based on Social Cost Function
Authors: Peñabaena-Niebles Rita , Cantillo Victor , Moura José Luis , Ibeas Angel
Published: October 2017

Signal plan transition is the process of changing from one timing plan to another. It begins when the first intersection starts adjusting signal timing plans and ends when the last intersection completes adjusting signal timing plans. The transition between signal timing plans is required because traffic patterns change during the day. Therefore, it is necessary to modify signal timing parameters offset, phase split, and cycle length for different expectations of traffic volume. This paper presents an alternative and new mathematical model to enhance the performance of traffic signals coordination at intersections during the transition phase. This model is oriented to describe the transition regarding coordination parameters in all intersections of an arterial road for minimizing the social cost during the transition phase expressed in function of costs due to delays, fuel consumption, and air emissions. An ant colony algorithm was designed, coded, and simulated to find the optimal transition parameters using available data. The model was evaluated based on its ability to minimize social costs during the transition period. Results showed that the proposed method performs better than traditional ones.
Regional Groundwater Quality Management through Hydrogeological Modeling in LCC, West Faisalabad, Pakistan
Authors: Shakoor Aamir , Mahmood Khan Zahid , Arshad Muhammad , Farid Hafiz Umar , Sultan Muhammad , Azmat Muhammad , Shahid Muhammad Adnan , Hussain Zafar
Published: October 2017

The intensive abstraction of groundwater is causing a number of problems such as groundwater depletion and quality deterioration. To manage such problems, the data of 256 piezometers regarding groundwater levels and quality were acquired for the period of 2003 to 2012 in command area of Lower Chenab Canal (LCC), West Faisalabad, Pakistan. MODFLOW and MT3D models were calibrated for the period of 2003–2007 and validated for years 2008–2012 with respect to observed groundwater levels and quality data, respectively. After the successful calibration and validation, two pumping scenarios were developed up to year 2030: Scenario I (increase in pumping rate according to the historical trend) and Scenario II (adjusted canal water supplies and groundwater patterns). The predicted results of Scenario I revealed that, up to year 2030, the area under good quality groundwater reduced significantly from 50.35 to 28.95%, while marginal and hazardous groundwater quality area increased from 49.65 to 71.06%. Under Scenario II, the good quality groundwater area increased to 6.32% and 12.48% area possesses less hazardous quality of groundwater. It was concluded that the canal water supply should shift from good quality aquifer zone to poor quality aquifer zone for proficient management of groundwater at the study area.
Dynamics of Insulin Secretion from EndoC-βH1β-Cell Pseudoislets in Response to Glucose and Other Nutrient and Nonnutrient Secretagogues
Authors: Teraoku Hiroki , Lenzen Sigurd
Published: October 2017

The dynamics of insulin secretion were characterized in response to a variety of physiological and pharmacological stimulators and other compounds in perifused pseudoislets generated from cells of the EndoC-βH1β-cell line. Perifusion of EndoC-βH1 pseudoislets with the physiological stimulus glucose (16.7 mM) induced sustained insulin secretion, which was inhibited by mannoheptulose. The adenylate cyclase activators IBMX and forskolin strongly potentiated this secretion. Glibenclamide, a Kir 6.2 potassium channel blocker, and Bay K 8644, an opener of the voltage-sensitive Ca2+channel, also potentiated glucose-induced insulin secretion. The dynamics of insulin secretion from EndoC-βH1 pseudoislets were characterized by an insulin secretory response to glucose starting within 1-2 min and passing over without interruption into a sustained phase of insulin release for the whole stimulation period. This lack of a transient decline between the first and the second phases of insulin release is an indication for a quick supply of insulin secretory granules from the reserve pool to the docking sites below the plasma membrane. Thereby, new secretory granules are directly made available for sustained exocytosis of insulin in EndoC-βH1β-cells. The study shows that EndoC-βH1β-cell pseudoislets are well suited for kinetic analyses of insulin secretion.