Synthesis of Cobalt Adhesion Promoters and Their Evaluation in a Passenger Radial-Belt Skim Compound

Cobalt adhesion promoters have gained considerable acceptance in the rubber industry during the past two decades and are considered the most important tool for the promotion of adhesion between the rubber compound and the brass-plated steel cord in the manufacture of steel-cord-reinforced radial tires. Most of the commercially available cobalt compounds are either higher fatty acid salts or cobalt–chelate complexes, e.g., cobalt octanoate, napthenate, stearate, and cobalt–boron complexes. Of the various cobalt salts and chelate complexes, cobalt–boron complexes are the most popular, and they form good bonding. Considering the availability, economics, and performance of this material, an attempt has been made in this study to synthesize different cobalt–chelate complexes, make a comparative evaluation of rubber compounds, and simulate field performance with laboratory tests.     

Conversion of neuronal growth cone responses from repulsion to attraction by cyclic nucleotides

Nerve growth is regulated by attractive and repulsive factors in the nervous system. Microscopic gradients of Collapsin-1/Semaphorin III/D (Sema III) and myelin-associated glycoprotein trigger repulsive turning responses by growth cones of cultured Xenopus spinal neurons; the repulsion can be converted to attraction by pharmacological activation of the guanosine 3',5'-monophosphate (cGMP) and adenosine 3',5'-monophosphate signaling pathways, respectively. Sema III also causes the collapse of cultured rat sensory growth cones, which can be inhibited by activation of the cGMP pathway. Thus cyclic nucleotides can regulate growth cone behaviors and may be targets for designing treatments to alleviate the inhibition of nerve regeneration by repulsive factors.     

File recovery by ISO FTAM

File recovery enhances the reliability and robustness of a network file management system. This capability of error detection and recovery is examined in an FTAM implementation. The issues of docket design, checkpoint insertion, recoverability, as well as interface transparency, are discussed in the paper. The impact of the recovery on the end-to-end performance and the effectiveness of the error recovery protocol in the light of failures are also examined by means of performance measurements. The result shows that the advantage gained by error recovery outweighs the protocol overheads incurred in the process.     

Application of a modified strain transient dip test in the determination of the internal stresses of PVC under tension

A modified strain transient dip test which involves the design of a load reduction apparatus to perform rapid step unloading and extrapolating to zero extension rate has been developed to measure the internal stresses (recovery and effective stress) of PVC under uniaxial tension. This simple technique appears to be consistent with other internal stress measurement techniques. It was found that the effective stress approaches a limiting value with applied strain and an extrapolated yield point could be defined. The limiting value is a function of the strain rate during the initial load application. The general increase in applied stress (at fixed applied strain) with crosshead speed was attributed to the increase in magnitude of the effective stress. The maximum peak ratio of effective over recovery stress, at each crosshead speed, could indicate that it was the energy-dissipating part of the material that played a dominant role in the early stages of the deformation while the energy-storage part dominated the latter stages.     

Polycrystalline diamond pressure sensor

The piezoresistance and other characteristics of boron doped polycrystalline diamond films (PDF's) were determined by analyzing free-standing films that had been formed on silicon. These structures were adhered to a dielectric substrate, and from bending stresses a gauge factor was estimated. Subsequently, a monolithic all-diamond pressure sensor was designed and fabricated, whereby doped diamond resistors reside on a dielectric diamond substrate diaphragm. The process and piezoresistance behavior of their structure is described     

Load balancing in the provisioning of hose model virtual private networks with multi-path routing

Load balancing in the provisioning of virtual private network (VPN) service in the hose model is studied. Single-path routing and tree routing for the hose model tend to aggregate bandwidth reservations on a small number of links, thus leading to congestion problems in service provider networks. If the link capacity is depleted as a result of improper routing, all future non-VPN traffic will be blocked. We propose a novel multi-objective multi-path (MOMP) routing linear program with the maximum fraction of traffic on a path (MFTP) constraint to solve the problem. The MOMP routing algorithm is able to reduce the bandwidth reservation on the most loaded link by as much as 50%, thus effectively alleviating the potential congestion problems in service provider network. The MFTP constraint provides a guarantee of the availability of multiple paths for each VPN endpoint pair. Further reduction of the bandwidth reservation can be achieved depending on the MFTP value. This is highly significant.     

Layered-routing approach for solving multicast routing and wavelength assignment problem

We have developed a new layered-routing approach to address the problem of all-optical multicast over wavelength-routed wavelength division multiplexing (WDM) networks. We model the WDM network as a collection of wavelength layers with sparse light- splitting (LS) and wavelength conversion (WC) capabilities. We apply the degree constraint technique to solve the problem. The approach is capable of completing multicast routing and wavelength assignment (MCRWA) in one step. We propose two generic frameworks to facilitate heuristic development. Any heuristic that is derived from either Prim’s or Kruskal’s algorithm can be easily imported to solve the MCRWA problem. One example is given for each framework to demonstrate heuristic development. Extensive simulations were carried out to measure the performance of heuristics developed from the frameworks. The results show that the STRIGENT scheme is suitable for hardware design and it is advisable to deploy light splitters and wavelength converters to the same node for better performance.     

Why patients fail to attend psychiatric outpatient follow-up: a pilot study

BACKGROUND/AIM: Traditionally, orthotopic liver transplantation has consisted of a total native hepatectomy that included retrohepatic inferior vena cava. The so-called "piggyback" technique was described by Tzakis et al. (2). It consists of a recipient hepatectomy with preservation of the native retrohepatic IVC and subsequent anastomosis of the homograft suprahepatic IVC to a cuff fashioned from the recipient's suprahepatic veins. In this study, a single surgeon's experience with both techniques during the same period of time is discussed to analyze any significant differences in survival, intraoperative blood loss, length of stay in the ICU, and total length of stay in the hospital. MATERIALS AND METHODS: Over a three year period, 128 patients were transplanted at the University of Pittsburgh. Of these, 66 patients (51.6%) had a piggyback (PB) operation while the remaining 62 (48.4%) had a "standard" (ST) operation. RESULTS: The actual 6 month survival was 81.8% in the PB group (54/66) and 74.2% in the ST group (46/62), with no statistical difference between the two. The median intraoperative blood usage was 6 units for the PB group versus 10 units for the ST group (p > 0.02). The median ICU length of stay was the same at 4 days, as was the total hospitalization duration, 21 days. The in-hospital deaths were included in the analysis. CONCLUSIONS: The piggyback technique has some advantages, including less bleeding and absence of brachial plexus or phrenic nerve injury. Several other important considerations are discussed. In conclusion, the results with the piggyback technique are equivalent to those obtained with the standard approach.     

Seamless handover integrated solution for video transmission over proxy mobile IPv6 in a micro mobility domain

Seamless communication is becoming one of the most important issues for the next generation of mobile and wireless networks. In this context, seamless is referred to users that are free to roam around different networks and at the same time stay connected without any disturbance to the ongoing session during the handover process from one network to another. The handover process between these networks spawns long delay or latency, high packet loss, and fewer throughputs which may degrade the performance of real-time applications during the handover process. Therefore, in order to resolve these problems, a new protocol has been proposed by Network-based Localized Mobility Management working group of Internet Engineering Task Force under network-based mobility management protocol. Although, this protocol managed to minimize the problems related to network switching, it still suffers several drawbacks during the handover process especially when the movement speed of mobile user is high. In this paper, we present a new approach which is a network-based mobility management protocol that aims to reduce the lengthy handover latency, jitter, high packet loss, and increase throughput and the performance of video transmission during the high speed mobility. The proposed approach namely Seamless Handover Integrated Solution consists of mobility prediction method, a set of Internet Control Message Protocol version 6 (ICMP6) messages which are effective in terms of handover optimization.