Noise Induced Phenomena in the Dynamics of Two Competing Species

Noise through its interaction with the nonlinearity of the living systems can give rise to counter-intuitive phenomena. In this paper we shortly review noise induced effects in different ecosystems, in which two populations compete for the same resources. We also present new results on spatial patterns of two populations, while modeling real distributions of anchovies and sardines. The transient dynamics of these ecosystems are analyzed through generalized Lotka-Volterra equations in the presence of multiplicative noise, which models the interaction between the species and the environment. We find noise induced phenomena such as quasi-deterministic oscillations, stochastic resonance, noise delayed extinction, and noise induced pattern formation. In addition, our theoretical results are validated with experimental findings. Specifically the results, obtained by a coupled map lattice model, well reproduce the spatial distributions of anchovies and sardines, observed in a marine ecosystem. Moreover, the experimental dynamical behavior of two competing bacterial populations in a meat product and the probability distribution at long times of one of them are well reproduced by a stochastic microbial predictive model.Comment: 23 pages, 8 figures; to be published in Math. Model. Nat. Phenom. (2016

Decoding Information From Neural Signals Recorded Using Intraneural Electrodes: Toward the Development of a Neurocontrolled Hand Prosthesis

The possibility of controlling dexterous hand prostheses by using a direct connection with the nervous system is particularly interesting for the significant improvement of the quality of life of patients, which can derive from this achievement. Among the various approaches, peripheral nerve based intrafascicular electrodes are excellent neural interface candidates, representing an excellent compromise between high selectivity and relatively low invasiveness. Moreover, this approach has undergone preliminary testing in human volunteers and has shown promise. In this paper, we investigate whether the use of intrafascicular electrodes can be used to decode multiple sensory and motor information channels with the aim to develop a finite state algorithm that may be employed to control neuroprostheses and neurocontrolled hand prostheses. The results achieved both in animal and human experiments show that the combination of multiple sites recordings and advanced signal processing techniques (such as wavelet denoising and spike sorting algorithms) can be used to identify both sensory stimuli (in animal models) and motor commands (in a human volunteer). These findings have interesting implications, which should be investigated in future experiments. © 2006 IEEE

Guess the State: Exploiting Determinism to Improve GUI Exploration Efficiency

Many automatic Web testing techniques generate test cases by analyzing the GUI of the Web applications under test, aiming to exercise sequences of actions that are similar to the ones that testers could manually execute. However, the efficiency of the test generation process is severely limited by the cost of analyzing the content of the GUI screens after executing each action. In this paper, we introduce an inference component, Sibilla, which accumulates knowledge about the behavior of the GUI after each action. Sibilla enables the test generators to reuse the results computed for GUI screens that recur multiple times during the test generation process, thus improving the efficiency of Web testing techniques. We experimented Sibilla with Web testing techniques based on three different GUI exploration strategies (Random, Depth-first, and Q-learning) and nine target systems, observing reductions from 22% to 96% of the test generation time

Protein kinase a distribution in meningioma

Deregulation of intracellular signal transduction pathways is a hallmark of cancer cells, clearly differentiating them from healthy cells. Differential intracellular distribution of the cAMP-dependent protein kinases (PKA) was previously detected in cell cultures and in vivo in glioblastoma and medulloblastoma. Our goal is to extend this observation to meningioma, to explore possible differences among tumors of different origins and prospective outcomes. The distribution of regulatory and catalytic subunits of PKA has been examined in tissue specimens obtained during surgery from meningioma patients. PKA RI subunit appeared more evenly distributed throughout the cytoplasm, but it was clearly detectable only in some tumors. RII was present in discrete spots, presumably at high local concentration; these aggregates could also be visualized under equilibrium binding conditions with fluorescent 8-substituted cAMP analogues, at variance with normal brain tissue and other brain tumors. The PKA catalytic subunit showed exactly overlapping pattern to RII and in fixed sections could be visualized by fluorescent cAMP analogues. Gene expression analysis showed that the PKA catalytic subunit revealed a significant correlation pattern with genes involved in meningioma. Hence, meningioma patients show a distinctive distribution pattern of PKA regulatory and catalytic subunits, different from glioblastoma, medulloblastoma, and healthy brain tissue. These observations raise the possibility of exploiting the PKA intracellular pathway as a diagnostic tool and possible therapeutic interventions

Uncovering the effect of low-frequency static magnetic field on tendon-derived cells: from mechanosensing to tenogenesis

Magnetotherapy has been receiving increased attention as an attractive strategy for modulating cell physiology directly at the site of injury, thereby providing the medical community with a safe and non- invasive therapy. Yet, how magnetic eld in uences tendon cells both at the cellular and molecular levels remains unclear. Thus, the in uence of a low-frequency static magnetic eld (2 Hz, 350 mT) on human tendon-derived cells was studied using di erent exposure times (4 and 8 h; short-term studies) and di erent regimens of exposure to an 8h-period of magnetic stimulation (continuous, every 24 h or every 48 h; long-term studies). Herein, 8 h stimulation in short-term studies signi cantly upregulated the expression of tendon-associated genes SCX, COL1A1, TNC and DCN (p < 0.05) and altered intracellular Ca2+ levels (p < 0.05). Additionally, every 24 h regimen of stimulation signi cantly upregulated COL1A1, COL3A1 and TNC at day 14 in comparison to control (p < 0.05), whereas continuous exposure di erentially regulated the release of the immunomodulatory cytokines IL-1β and IL-10 (p < 0.001) but only at day 7 in comparison to controls. Altogether, these results provide new insights on how low-frequency static magnetic eld ne-tune the behaviour of tendon cells according to the magnetic settings used, which we foresee to represent an interesting candidate to guide tendon regeneration.info:eu-repo/semantics/publishedVersio

On Safety Enhancement in IIoT Scenarios through Heterogeneous Localization Techniques

In the field of the Industrial Internet of Things (IIoT), strictly related to Industry 4.0, one of the main aspects to be carefully considered by the governing board of a manufacturing company is the safety level to be guaranteed to the workers inside production plants. This involves daily human activities, together with production machines to be used during the working hour (and periodically maintained), and mobile industrial vehicles moving around the production plant. To this end, a precise localization of both workers and vehicles is expedient to improve the safety level—avoiding that people move inside forbidden areas or perform dangerous actions—as well as allowing a more accurate control and reporting to national authorities in charge of verifying the compliance to safety regulations (e.g., aggregated data, not shared outside the company, used to fill injuries reports in case of official inspections), in the presence of accidents and anomalous events. In this paper, we present the design of IIoT-related localization mechanisms exploiting heterogeneous communication technologies, in turn analysing how the localization can cope with the adoption of wideband (e.g., Wi-Fi) and narrowband (e.g., Narrowband IoT, NB-IoT) communication protocols and discussing how these communication paradigms may impact existing and modern production plants

Polyphenol characterization and skin-preserving properties of hydroalcoholic flower extract from Himantoglossum robertianum (Orchidaceae)

Himantoglossum robertianum (Loisel.) P. Delforge is a Mediterranean orchid whose propagation in vitro has been achieved, making it eligible as a source of bioactive substances. Flowers were analyzed by light and SEM microscopy and used to obtain a polyphenol-rich, hydroalcoholic flower extract (HFE). HFE was characterized for total phenols, flavonoids and proanthocyanidins, and for polyphenol profile by RP-LC-DAD. Antioxidant assays, in vitro collagenase and elastase inhibition, and MTT and cell motility assays on HaCaT keratinocytes were done. Microscopy showed epidermal cells containing anthocyanins in the flower labellum. Flavonoids (flavones and flavan-3-ols) represented the most abundant compounds (42.91%), followed by scopoletin (33.79%), and phenolic acids (23.3%). Antioxidant assays showed strong activities, rating ORAC &gt; FRAP &gt; TEAC &gt; \u3b2-carotene bleaching &gt; DPPH &gt; iron-chelation. Biological assays showed elastase and collagenase inhibition (up to 42% and 78%, respectively), improvement of HaCaT cell viability after treatment with 500 \u3bcM H2O2 (from 30% to 84% of control), and stimulation of cell migration rate up to 210% of control. In summary, HFE counteracted different free radicals, while protective properties were shown by cell-free and cell-based bioassays, suggesting the possible use of H. robertianum flowers for skin-preserving, repair, and anti-aging applications

A new mini-open technique of arthroscopically assisted Latarjet

Background: The aim is to describe a new arthroscopically assisted Latarjet technique. Methods: We evaluated the clinical and radiological findings of 60 patients with chronic recurrent anterior gleno-humeral instability who underwent, between September 2013 and November 2014, an arthroscopically-assisted Latarjet procedure with double round endobutton fixation. Inclusion criteria were: chronic anterior recurrent instability, Instability Severity Index Score (ISIS) greater than three points, a glenoid bone defect &gt; 15% or a Hill Sachs lesion with concomitant glenoid bone defect &gt; 10%. During surgery the joint capsule and the anterior glenoid labrum were detached. Two drill tunnels perpendicular to the neck of the glenoid were made through a guide. An accessible pilot hole through the glenoid was created to allows the passage of guidewires for coracoid guidance and final fixation onto the anterior glenoid. Through a restricted deltopectoral access a coracoid osteotomy was made. Finally, the graft was prepared, inserted and secured using half-stitches. Results: The mean follow-up was 32.5 months (range 24\u201332 months). At a mean follow-up, 56 of the 60 subjects claimed a stable shoulder without postoperative complaints, two (3.3%) had an anterior dislocation after new traumatic injury, and two (3.3%) complained of subjective instability. At the latest follow-up, four subjects complained of painful recurrent anterior instability during abduction-external rotation with apprehension. At 1 year, the graft had migrated in one patient (1.7%) and judged not healed and high positioned in another patient (1.7%). Moreover, a glenoid bony gain of 26.3% was recorded. At the latest follow-up, three patients had grade 1 according to Samilson and Prieto classification asymptomatic degenerative changes. Nerve injuries and infections were not detected. None of the 60 patients underwent revision surgery. Healing rate of the graft was 96.7%. Conclusions: This technique of arthroscopically assisted Latarjet combines mini-open and arthroscopic approach for improving the precision of the bony tunnels in the glenoid and coracoid placement, minimizing any potential risk of neurologic complications. It can be an option in subjects with anterior gleno-humeral instability and glenoid bone defect. Further studies should be performed to confirm our preliminary results