Simplified dipole concept for the assessment of transient electromagnetic field in the vicinity of grounding grid

The objective of this work is to provide a simplified model to analyse the electromagnetic emission of the grounding grid thus enabling engineers to perform parametric studies rapidly without greater loss of accuracy. The proposed approach is based on the use of the transmission line theory and the concept of dipole radiation in the presence of a lossy half‐space including the Sommerfeld integral approach. The model proposes to determine the electromagnetic fields (soil and air) and current distribution in a grounding system. The proposed model is described and illustrated with applications. The limitations and advantages are also discussed and compared against antenna theory counter parts. Copyright © 2014 John Wiley & Sons, Ltd.     

Survey on IoV routing protocols: Security and network architecture

As today, vehicles are equipped with wireless sensors and on‐board computers capable of collecting and processing a large amount of data; they can communicate to each other via different communication types and through different relay nodes. Internet of Vehicles (IoV) routing protocols are deployed to monitor these communications with various strategies to achieve a high availability of communication. In this paper, we propose to extend an existing taxonomy representing the necessary criteria to build IoV routing algorithms, by adding two new important criteria: security aspect and network architecture. Enhanced vehicular routing protocols with different security mechanisms have been studied, compared, and classified with respect to the authentication, the integrity, the confidentiality, the nonrepudiation, and the availability of data and communications. Routing protocols using the software‐defined networking (SDN) paradigm have also been reviewed in order to compare with those with traditional network architectures. Three types of SDN routing protocols, namely, centralized, decentralized, and hybrid control planes, have been analyzed. This survey will be useful for the choice of IoV routing protocols that take into account the flexibility, the scalability, and the intelligence of vehicular networks, as well as the security mechanisms against cyberattacks while being cost aware.     

Increased incidence of sepsis at birth in neutropenic infants of mothers with preeclampsia

Neutropenia is often found at birth in infants born to mothers with preeclampsia, and is most likely present in utero. To determine whether this neutropenia is associated with an increased incidence of early-onset sepsis, we reviewed the hospital records of 301 low birth weight infants of mothers with preeclampsia. Early-onset sepsis was proved if the result of a culture of blood or cerebrospinal fluid in the first 48 hours of life was positive, or presumed if culture results were negative but two or more clinical signs of sepsis were present and the attending neonatologist believed that an infant was infected and needed at least 7 days of antibiotic therapy. Forty-eight percent of low birth weight infants of mothers with preeclampsia had neutropenia at less than 12 hours of age. Infants with neutropenia had mothers with more severe preeclampsia, were more premature (30 weeks vs 32 weeks), weighed less (1097 gm vs 1615 gm), and were more likely to be small for gestational age. Although maternal and obstetric risk factors for infection were less common in the group with neutropenia, rates of proven or presumed early-onset sepsis were higher (14% vs 2%; p < 0.001). Sepsis was proved in 6% of infants with neutropenia and in none of the infants without neutropenia (p = 0.03). A logistic regression analysis of the relative effects of birth weight, gestational age, and absolute neutrophil count on the incidence of sepsis revealed that only a low absolute neutrophil count correlated significantly with an increased risk of early-onset sepsis in infants with neutropenia.     

C?C Bond Formation via C?H Activation and C?N Bond Formation via Oxidative Amination Catalyzed by Palladium‐ Polyoxometalate Nanomaterials Using Dioxygen as the Terminal Oxidant

An efficient heterogeneous palladium‐polyoxometalate catalyst with the formula Pd‐H₆PV₃Mo₉O₄₀/C has been successfully developed for carbon‐carbon (C C) bond formation via carbon‐hydrogen (C H) activation and carbon‐nitrogen (C N) bond formation via oxidative amination using oxygen as the terminal oxidant. The coupling processes are simple, and use relatively mild conditions to form the desired products. In addition, less waste is generated as no additional reagents such as organic/inorganic oxidants are required, and water is the only by‐product generated.     

Signal transduction in gastrointestinal smooth muscle

Signal transduction in gastric and intestinal smooth muscle is mediated by receptors coupled via distinct G proteins to various effector enzymes, including PI-specific PLC-beta 1 and PLC-beta 3, and phosphatidylcholine (PC)-specific PLC, PLD and PLA2. Activation of these enzymes is different in circular and longitudinal muscle cells, generating Ca(2+)-mobilizing (IP3, AA, cADPR) and other (DAG) messengers responsible for the initial and sustained phases of contraction, respectively. IP3-dependent Ca2+ release occurs only in circular muscle. Ca2+ mobilization in longitudinal muscle involves a cascade initiated by agonist-induced transient activation of PLA2 and formation of AA, AA-dependent depolarization of the plasma membrane and opening of voltage-sensitive Ca2+ channels. The influx of Ca2+ induces Ca2+ release by activating sarcoplasmic ryanodine receptor/Ca2+ channel and stimulates cADPR formation which enhances Ca(2+)-induced Ca2+ release. The initial [Ca2+]i transient in both muscle cell types results in Ca2+/calmodulin-dependent activation of MLC kinase, phosphorylation of MLC20 and interaction of actin and myosin. The sustained phase is mediated by a Ca(2+)-independent isoform of PKC, PKC-epsilon DAG for this process is generated by PLC- and PLD-mediated hydrolysis of PC. Relaxation is mediated by cAMP-and/or cGMP-dependent protein kinase which inhibit the initial [Ca2+]i transient and reduce the sensitivity of MLC kinase to [Ca2+]i. Relaxation induced by the main neurotransmitters, VIP and PACAP, involves two cascades, one of which reflects activation of adenylyl cyclase. A distinct cascade involves G-protein-dependent stimulation of Ca2+ influx leading to Ca2+/calmodulin-dependent activation of a constitutive eNOS in muscle cells; the generation of NO activates soluble guanylyl cyclase. The resultant activation of PKA and PKG is jointly responsible for muscle relaxation.     

Drying of Garlic (Allium sativum) and Its Effect on Allicin Retention

Convective hot air-drying and freeze-drying were investigated as potential processes to preserve and concentrate allicin in garlic. Both temperature and air velocity had an important effect on hot air-drying kinetics. Sample size and temperature significantly affected the duration of freeze-drying, and thus the remaining moisture content of the garlic samples. Allicin content decreased with an increase of drying temperature in both convective hot air-drying or freeze-drying. Moderate air temperatures (40 and 50°C) allowed a better allicin retention than higher temperatures (60°C). However, retention of allicin was more important in garlic samples freeze-dried at a temperature of 20°C. The drying method did not show a significant impact on glass transition temperature values, indicating that garlic composition is a more important factor than internal structure. The predictions of the Gordon and Taylor model are in good agreement with the experimental data.     

Feature construction as a bi-level optimization problem

Neural Computing and Applications - Feature selection and construction are important preprocessing techniques in data mining. They allow not only dimensionality reduction but also classification...     

SE-AOMDV: secure and efficient AOMDV routing protocol for vehicular communications

International Journal of Information Security - The Vehicular Ad hoc Networks (VANETs) are emerging networks that provide essential services to drivers on the road. To exchange data, vehicles as...