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We define a weaker Meir-Keeler type function and establish the fixed point theorems for a weaker Meir-Keeler type -set contraction in metric spaces.

In this work, we introduce the concept of cone ball-metric spaces and we prove fixed point results on such spaces for mappings satisfying a contraction involving a stronger Meir–Keeler cone-type function.

In this work, we first define the asymptotic pointwise weaker Meir–Keeler-type ψ -contraction, ψ : X → ℜ + , and then a simple proof for the existence of fixed point theorems for the asymptotic pointwise weaker Meir–Keeler-type ψ -contraction is given.

Background Butylidenephthalide (Bdph), a main constituent of Ligusticum chuanxiong Hort., was reported to have selective antianginal effect without changing blood pressure in conscious rat. Recently, we have observed that Bdph antagonized cromakalim, an ATP-dependent K+ channel opener, in guinea-pig trachea. Thus, we were interested in investigating whether Bdph at the dose without changing blood pressure antagonized cromakalim-induced systolic pressure reduction in conscious rats. Methods Systolic arterial pressures of conscious rats were determined by using the indirect tail-cuff method. Results Bdph (30 mg/kg, i.p.) did not affect baseline systolic pressure in conscious normotensive and spontaneous hypertensive rats. Bdph (30 mg/kg, i.p.) also did not affect log dose–response curves of prazosin, clonidine and Bay K 8644, a Ca2+ channel activator, in normotensive rats. However, Bdph (30 mg/kg, i.p.) similar to 4-aminopyridine (4-AP, 0.4 mg/kg, i.p.), a K+ channel blocker, non-parallelly but surmountably, and partially similar to glibenclamide (GBC, 10 mg/kg, i.v.), an ATP-sensitive K+ channel blocker, surmountably but not parallelly rightward shifted the log dose-systolic pressure reduction curve of cromakalim, an ATP-sensitive K+ channel opener, in normotensive rats, respectively. Discussion The antagonistic effect of Bdph against cromakalim was similar to that of 4-AP, a K+ channel blocker of Kv1 family, and partially similar to that of GBC, an ATP-sensitive K+ channel blocker. Thus, Bdph may be a kind of K+ channel blockers, which have been reviewed to have a potential clinical use for Alzheimer disease. Indeed, Bdph has also been reported to reverse the deficits of inhibitory avoidance performance and improve memory in rats. Recently, 4-AP was reported to treat Episodic ataxia type 2 (EA2) which is a form of hereditary neurological disorder. Consistently, Bdph was recently reported to have antihyperglycemic activity in mice, since GBC is a powerful oral hypoglycemic drug. Conclusions Bdph similar to 4-AP and partially similar to GBC may block Kv1 family and ATP-sensitive K+ channels in conscious normotensive rats.

Background With millisecond-level resolution, electroencephalographic (EEG) recording provides a sensitive tool to assay neural dynamics of human cognition. However, selection of EEG features used to answer experimental questions is typically determined a priori. The utility of machine learning was investigated as a computational framework for extracting the most relevant features from EEG data empirically. Methods Schizophrenia (SZ; n = 40) and healthy community (HC; n = 12) subjects completed a Sternberg Working Memory Task (SWMT) during EEG recording. EEG was analyzed to extract 5 frequency components (theta1, theta2, alpha, beta, gamma) at 4 processing stages (baseline, encoding, retention, retrieval) and 3 scalp sites (frontal-Fz, central-Cz, occipital-Oz) separately for correctly and incorrectly answered trials. The 1-norm support vector machine (SVM) method was used to build EEG classifiers of SWMT trial accuracy (correct vs. incorrect; Model 1) and diagnosis (HC vs. SZ; Model 2). External validity of SVM models was examined in relation to neuropsychological test performance and diagnostic classification using conventional regression-based analyses. Results SWMT performance was significantly reduced in SZ (p < .001). Model 1 correctly classified trial accuracy at 84 % in HC, and at 74 % when cross-validated in SZ data. Frontal gamma at encoding and central theta at retention provided highest weightings, accounting for 76 % of variance in SWMT scores and 42 % variance in neuropsychological test performance across samples. Model 2 identified frontal theta at baseline and frontal alpha during retrieval as primary classifiers of diagnosis, providing 87 % classification accuracy as a discriminant function. Conclusions EEG features derived by SVM are consistent with literature reports of gamma’s role in memory encoding, engagement of theta during memory retention, and elevated resting low-frequency activity in schizophrenia. Tests of model performance and cross-validation support the stability and generalizability of results, and utility of SVM as an analytic approach for EEG feature selection.

In this paper, we introduce the notions of soft Meir-Keeler contractive mappings and weaker ϕ-Meir-Keeler contractive mappings, and the purpose of this paper is to prove two theorems which assures the existence of fixed points for these two soft Meir-Keeler type contractive mappings on a soft metric space. Our results generalize and improve many recent fixed point results in the literature.

In this article, for a tυs-G-cone metric space (X, G) and for the family A of subsets of X, we introduce a new notion of the tυs - H -c one metric H with respect to G, and we get a fixed result for the stronger Meir-Keeler-G-cone-type function in a complete tυs-G-cone metric space (A,H) Our result generalizes some recent results due to Dariusz Wardowski and Radonevic’ et al. MSC: 47H10; 54C60; 54H25; 55M20.

We use a concept of abstract convexity to define the almost - property, al- - family, and almost -spaces. We get some new approximate fixed point theorems and fixed point theorems in almost -spaces. Our results extend some results of other authors.

BackgroundHesperetin was reported to selectively inhibit phosphodiesterase 4 (PDE4). While hesperetin-7,3'-O-dimethylether (HDME) is a synthetic liposoluble hesperetin. Therefore, we were interested in investigating its selectivity on PDE4 and binding ability on high-affinity rolipram-binding sites (HARBs)in vitro, and its effects on ovalbumin-induced airway hyperresponsivenessin vivo, and clarifying its potential for treating asthma and chronic obstructive pulmonary disease (COPD).MethodsPDE1~5 activities were measured using a two-step procedure. The binding of HDME on high-affinity rolipram-binding sites was determined by replacing 2 nM [3H]-rolipram. AHR was assessed using the FlexiVent system and barometric plethysmography. Inflammatory cells were counted using a hemocytometer. Cytokines were determined using mouse T helper (Th)1/Th2 cytokine CBA kits, and total immunoglobulin (Ig)E or IgG2alevels were done using ELISA method. Xylazine (10 mg/kg)/ketamine (70 mg/kg)-induced anesthesia was performed.ResultsHDME revealed selective phosphodiesterase 4 (PDE4) inhibition with a therapeutic (PDE4H/PDE4L) ratio of 35.5in vitro.In vivo, HDME (3~30 μmol/kg, orally (p.o.)) dose-dependently and significantly attenuated the airway resistance (RL) and increased lung dynamic compliance (Cdyn), and decreased enhanced pause (Penh) values induced by methacholine in sensitized and challenged mice. It also significantly suppressed the increases in the numbers of total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, and levels of cytokines, including interleukin (IL)-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor-α in bronchoalveolar lavage fluid (BALF) of these mice. In addition, HDME (3~30 μmol/kg, p.o.) dose-dependently and significantly suppressed total and ovalbumin-specific immunoglobulin (Ig)E levels in the BALF and serum, and enhanced IgG2alevel in the serum of these mice.ConclusionsHDME exerted anti-inflammatory effects, including suppression of AHR, and reduced expressions of inflammatory cells and cytokines in this murine model, which appears to be suitable for studying the effects of drugs on atypical asthma and COPD, and for screening those on typical asthma. However, HDME did not influnce xylazine/ketamine-induced anesthesia. Thus HDME may have the potential for use in treating typical and atypical asthma, and COPD.

In this paper, we introduce two iterative algorithms for finding common solutions of a finite family of variational inclusions for maximal monotone and inverse-strongly monotone mappings with the constraints of two problems: a generalized mixed equilibrium problem and a common fixed point problem of an infinite family of nonexpansive mappings and an asymptotically strict pseudocontractive mapping in the intermediate sense in a real Hilbert space. We prove some strong and weak convergence theorems for the proposed iterative algorithms under suitable conditions. MSC:49J30, 47H09, 47J20, 49M05.

In this article, by using the Meir-Keeler type mappings, we obtain some new fixed point theorems for the cyclic orbital stronger (weaker) Meir-Keeler contractions and generalized cyclic stronger (weaker) Meir-Keeler contractions. Our results generalize or improve many recent fixed point theorems in the literature. Mathematical Subject Classification: 54H25; 47H10

The purpose of this paper is to study fixed point theorems for a multi-valued mapping satisfying the α-Meir-Keeler contraction with respect to the partial Hausdorff metric ℋ in complete partial metric spaces. Our result generalizes and extends some results in the literature.

The purpose of this paper is to study fixed point theorems for a mapping satisfying the cyclical generalized contractive conditions in complete partial metric spaces. Our results generalize or improve many recent fixed point theorems in the literature.

In this article, we introduce the notions of (ϕ - φ)-weak contraction mappings and (ψ - φ)-weak contraction mappings in complete generalized metric spaces and prove two theorems which assure the existence of a periodic point for these two types of weak contraction.

Recent advances in wireless client devices and multimedia communications have motivated relevant standardization efforts, such as the IP Multimedia Subsystem (IMS) to support session control, mobility, and interoperability in all-IP next generation networks. Notwithstanding the central relevance of IMS for novel mobile multimedia services, IMS-based solutions still exhibit limited support for service continuity during handoffs, by omitting advanced techniques to reduce/eliminate handoff delays and quality degradations, especially during vertical handoffs. We propose an original solution for service continuity and dynamic multimedia content tailoring based on the primary design guideline of exploiting terminal-based decentralized handoff predictions to proactively activate application-level management operations (flow quality downscaling). The proposal is fully compliant with standard IMS and exploits infrastructure media gateways to execute content tailoring actions, without requiring heavy client-side adaptation operations. The reported experimental results point out that our solution can avoid streaming playout interruptions and significantly increase user-perceived service quality, without negative effects on handoff delay.

Recent research activities have recognized the relevant role of k-hop clustering in Mobile Ad Hoc NETworks (MANET). k-hop clustering determination and maintenance is especially crucial to achieve scalability in large MANET scenarios, where a high number of mobile terminals dynamically build collaboration communities in ad hoc mod. Some first solutions have recently appeared in order to exploit k-hop clustering to effectively build an optimal backbone (crucial to achieve scalability) connecting all determined clusterheads in fixed ad hoc networks. However, few papers in the literature have addressed the innovative issue of evaluating how node mobility quantitatively affects the degradation of clustering quality as time passes by. To the best of our knowledge, the most relevant contribution is (Bettstetter and Krausser, 2001), where the stability of DMAC single-hop clustering is evaluated via ideal coarse-grained discrete-step simulations, by neglecting low-layer communication issues. Our paper significantly extends that contribution, (i) by focusing on k-hop clustering; (ii) by proposing a simple updating protocol to maintain clustering quality notwithstanding node mobility; (iii) by introducing a novel intuitive metric to evaluate the effects of mobility on clustering consistency; and (iv) by reporting a relevantly wider set of more realistic simulations based on ns2.

In the modern Internet of services scenarios, users need to create, share and access contents and services in extremely personalized ways and by means of heterogeneous devices and interaction channels. The most promising architectural solutions to cope with such dynamic and ever-growing scenario adopt a service oriented approach and leverage service composition platforms to flexibly arrange new value-added services made up of basic off-the-shelf components. Though, current solutions for service composition target rather static scenarios and scarcely support today's dynamic Web, where new services and contents continually become available to satisfy novel user needs and service compositions may become obsolete and need reconfiguration. We propose a novel composition model that aims at being extremely flexible and extensible, yet remaining easily usable by hiding complexity to users.

The rapid diffusion of heterogeneous forms of wireless connectivity is pushing the tremendous growth of the commercial interest in mobile services, i.e., distributed applications to portable wireless terminals that roam during service provisioning. In the case of both location-dependent mobile services and mobile services with session continuity requirements, there is a growing need for decentralized and lightweight solutions to predict cell handovers, in order to enable proactive service management operations that anticipate actual terminal reconnections at their newly visited cells. The paper discusses how to predict client handovers between IEEE 802.11 cells in a portable and completely decentralized way, only by exploiting RSSI monitoring and with no need of external global positioning systems. In particular, the paper focuses on proposing and comparing different filtering techniques for mitigating Received Signal Strength Indication abrupt fluctuations. Experimental results point out that i) filtering techniques can relevantly improve the efficiency and effectiveness of handover prediction, and ii) the choice of the most appropriate filtering solution to adopt should be made at provisioning time depending on specific service/system requirements, e.g., privileging minimum overhead vs. greater prediction proactivity.

For an Internet Service Provider (ISP), the knowledge of which interdomain paths could be traversed by its BGP announcements - and thus traffic flows - is essential to predict the impact of network faults, to develop effective traffic engineering and peering strategies, and to assess the quality of upstream providers. However, current methodologies do not provide this information. We present methodologies to discover how the BGP announcements for an ISP’s prefix are propagated through the Internet using withdrawals and specially crafted AS-sets. The techniques allow an ISP to determine which paths could be traversed in the presence of network faults or different routing policies on the ISP’s part and to deduce the routing policies of other ISPs with respect to its network. We validate our techniques through experimentation in the IPv6 and IPv4 Internet, showing that they can be safely and effectively applied in real-world situations.

Handheld devices are becoming an integral part of every day life in the home, office, and on the road. Furthermore, mobile devices are a key ingredient in the pervasive environments. To be effective, those devices need to be thrifty in power consumption, attentive to user intentions and environment changes and should be easily managed. Several sensor based applications such as GPS mapping, finger print based authentication, and accelerometer based hard disk protection are becoming popular in small hand held devices. In this paper, a formalized architecture is proposed to allow systematic access and use of low cost sensors that are being built into small hand held systems for various end user functions. Preliminary results of the impact of using sensors to save power in the mobile architecture based on various policies are shown. The low power platform used for the experiments and measurement of results is a concept platform developed at Intel® Labs. The sensor-board used in this project is made at ARCES Labs (University of Bologna), funded by *Ducati Sistemi S.p.A. and MIUR.