Search results for "Erk"
showing 10 items of 2599 documents
A Comprehensive Survey on Cooperative Relaying and Jamming Strategies for Physical Layer Security
2019
Physical layer security (PLS) has been extensively explored as an alternative to conventional cryptographic schemes for securing wireless links. Many studies have shown that the cooperation between the legitimate nodes of a network can significantly enhance their secret communications performance, relative to the noncooperative case. Motivated by the importance of this class of PLS systems, this paper provides a comprehensive survey of the recent works on cooperative relaying and jamming techniques for securing wireless transmissions against eavesdropping nodes, which attempt to intercept the transmissions. First, it provides a in-depth overview of various secure relaying strategies and sch…
Effect of a Heavy Rainstorm on the Surface Hydrodynamic Properties of a Sandy-Loam Soil
2022
Changes in surface-soil hydrodynamic properties associated with torrential natural rainstorms are largely unknown. This investigation aimed at verifying if the surface hydrodynamic properties of a sandy-loam soil varied due to the heavy rainfall event (130 mm in nearly three hours) that occurred in the summer of 2020 at Palermo (Italy) and also to establish if soil recovery processes occurred soon after the event. The soil of an orchard was sampled immediately before the rainstorm and a few days and 1.5 months later. The rainstorm determined a moderate decrease (by 1.8 times) of the saturated soil hydraulic conductivity, Ks, and an increase of its relative variability. In the subsequent wee…
A test of water pouring height and run intermittence effects on single-ring infiltration rates
2018
Assessing how the infiltration process depends on the water impact energy improves interpretation of hydrological processes. Impact energies vary with the height of water pouring; that is, the distance between the water delivery point and the soil surface. The effects of the height of water pouring on infiltration in an initially near saturated soil can be tested in the field by two repeated Beerkan infiltration runs separated by a short pause (30 min) and using both low (non-perturbing) and high (perturbing) heights of water application. The double two-stage Beerkan run methodology was applied in two soils. The infiltration rate at the end of the perturbing stage of the experiment was 0.2–…
Determining short-term changes in the hydraulic properties of a sandy-loam soil by a three-run infiltration experiment
2020
Soil structure-dependent parameters can vary rapidly as a consequence of perturbing events such as intense rainfall. Investigating their short-term changes is therefore essential to understand the general behaviour of a porous medium. The aim of this study is to gain insight into the effects of wetting, perturbation and recovery processes through different sequences of Beerkan infiltration experiments performed on a sandy-loam soil. Two different three-run infiltration experiments (LHL and LLL) were carried out by pouring water at low (L, non-perturbing) and high (H, perturbing) heights above the soil surface and at short time intervals (hours, days). The results demonstrate that the propos…
Water transmission properties of a sandy-loam soil estimated with Beerkan runs differing by the infiltration time criterion
2021
Abstract The Beerkan method consists of a ponded infiltration experiment from a single ring inserted a small depth into the soil. Fixed, small volumes of water are repeatedly poured into the ring to maintain a quasi-zero head on the soil surface. According to the standard Beerkan infiltration run, a new water volume is poured on the infiltration surface when the previously applied volume has completely infiltrated and the soil surface is entirely exposed to air (ta criterion). However, water could also be applied when the soil exposition to air begins (to criterion) or half the soil surface is exposed to air (tm criterion). The effect of the infiltration time criterion on determination of t…
First Experimental Determination of the Ionization Potentials of Berkelium and Californium
1996
Mentoring of newly qualified teachers. A bilateral comparison between Germany and Finland
2017
Mentoring stellt in der Begleitung von in den Beruf einsteigenden Lehrpersonen eine international gängige Praxis dar. Ausgehend von theoretischen und empirisch fundierten Annahmen wird in diesem Beitrag der Ansatz der practice architectures genutzt, um Formen des Mentorings in Deutschland und Finnland im Hinblick auf länderspezifische Verständnisse vom Berufseinstieg von Lehrpersonen und deren Professionalisierung zu untersuchen. (DIPF/Orig.) Internationally, mentoring is a well-recognized practice in supporting newly qualified teachers. Based on theoretical and empirical understanding, this paper compares mentoring practices in two countries: Germany and Finland. The theoretical framework …
Biphasic Erk1/2 activation sequentially involving Gs and Gi signaling is required in beta3-adrenergic receptor-induced primary smooth muscle cell pro…
2013
Abstract The beta3 adrenergic receptor (B3-AR) reportedly induces cell proliferation, but the signaling pathways that were proposed, involving either Gs or Gi coupling, remain controversial. To further investigate the role of G protein coupling in B3-AR induced proliferation, we stimulated primary human myometrial smooth muscle cells with SAR150640 (B3-AR agonist) in the absence or presence of variable G-protein inhibitors. Specific B3-AR stimulation led to an Erk1/2 induced proliferation. We observed that the proliferative effects of B3-AR require two Erk1/2 activation peaks (the first after 3 min, the second at 8 h). Erk1/2 activation at 3 min was mimicked by forskolin (adenylyl-cyclase a…
Towards Service-oriented 5G: Virtualizing the Networks for Everything-as-a-Service
2018
It is widely acknowledged that the forthcoming 5G architecture will be highly heterogeneous and deployed with a high degree of density. These changes over the current 4G bring many challenges on how to achieve an efficient operation from the network management perspective. In this article, we introduce a revolutionary vision of the future 5G wireless networks, in which the network is no longer limited by hardware or even software. Specifically, by the idea of virtualizing the wireless networks, which has recently gained increasing attention, we introduce the Everything-as-a-Service (XaaS) taxonomy to light the way towards designing the service-oriented wireless networks. The concepts, chall…
A modified niche model for generating food webs with stage-structured consumers : The stabilizing effects of life-history stages on complex food webs
2021
1. Almost all organisms grow in size during their lifetime and switch diets, trophic positions, and interacting partners as they grow. Such ontogenetic development introduces life-history stages and flows of biomass between the stages through growth and reproduction. However, current research on complex food webs rarely considers life-history stages. The few previously proposed methods do not take full advantage of the existing food web structural models that can produce realistic food web topologies. 2. We extended the niche model by Williams & Martinez (2000) to generate food webs that included trophic species with a life-history stage structure. Our method aggregated trophic species …