Design and performance analysis of an Integrated Voice/Data (IVD) protocol for a token ring network

A high performance integrated voice/data (IVD) protocol for token ring networks that operates over a wide range of data traffic levels is developed and analyzed in this dissertation;The problems raised by integrating voice/data in local area networks are identified. These problems include variable network access delay and end-to-end delay limit of voice packets, and queueing delay of data packets;In the design of the IVD protocol, a packet format is selected, conditions for selecting network parameters are derived, and a channel allocation strategy is described to provide high quality of voice over a wide range of data traffic levels while preserving satisfactory data performance;The implementation issues, specification, and operation of the proposed protocol are described based on the standard IEEE 802.5 token ring protocol. The implementation issues are studied for two principal purposes: not to modify the operating data protocol and to utilize the bandwidth for data packets when voice stations are idle. A state transition diagram is used to specify the proposed protocol;A discrete-event model of the proposed IVD protocol is developed for the accurate performance evaluation of data and real-time voice traffic. In modeling the protocol, all the necessary information which affects the state of the system are considered including location of stations;The voice/data performance of the proposed IVD token ring protocol is evaluated and the effects of voice on data and vice versa are studied. The proposed protocol provides high quality of voice without a large degradation on the data performance over a wide range of data loads

Topological Massive Gauge Theories in Three Dimensions Based on the Faddeev-Jackiw Formalism

We quantize the (2+1)-dimensional self-dual and Maxwell-Chern-Simons theories by using the Faddeev-Jackiw formulation and compare the results with those of the Dirac formalism.Comment: 13 Pages, latex, no figure

Cigarette smoke exacerbates mouse allergic asthma through Smad proteins expressed in mast cells

<p>Abstract</p> <p>Background</p> <p>Many studies have found that smoking reduces lung function, but the relationship between cigarette smoke and allergic asthma has not been clearly elucidated, particularly the role of mast cells. This study aimed to investigate the effects of smoke exposure on allergic asthma and its association with mast cells.</p> <p>Methods</p> <p>BALB/c mice were sensitized and challenged by OVA to induce asthma, and bone marrow-derived mast cells (BMMCs) were stimulated with antigen/antibody reaction. Mice or BMMCs were exposed to cigarette smoke or CSE solution for 1 mo or 6 h, respectively. The recruitment of inflammatory cells into BAL fluid or lung tissues was determined by Diff-Quik or H&E staining, collagen deposition by Sircol assay, penh values by a whole-body plethysmography, co-localization of tryptase and Smad3 by immunohistochemistry, IgE and TGF-β level by ELISA, expressions of Smads proteins, activities of signaling molecules, or TGF-β mRNA by immunoblotting and RT-PCR.</p> <p>Results</p> <p>Cigarette smoke enhanced OVA-specific IgE levels, penh values, recruitment of inflammatory cells including mast cells, expressions of smad family, TGF-β mRNA and proteins, and cytokines, phosphorylations of Smad2 and 3, and MAP kinases, co-localization of tryptase and Smad3, and collagen deposition more than those of BAL cells and lung tissues of OVA-induced allergic mice. CSE solution pretreatment enhanced expressions of TGF-β, Smad3, activities of MAP kinases, NF-κB/AP-1 or PAI-1 more than those of activated-BMMCs.</p> <p>Conclusions</p> <p>The data suggest that smoke exposure enhances antigen-induced mast cell activation via TGF-β/Smad signaling pathways in mouse allergic asthma, and that it exacerbates airway inflammation and remodeling.</p

Synthesis and Characterization of SiO2 Coated γ-Fe2O3 Nanocomposite Powder for Hyperthermic Application

SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2 coated γ-Fe2O3 nanocomposite powder which means the magnetic heating effect under alternative magnetic field was much higher than the single phase γ-Fe2O3 nano powder due to the very fine size under 20 nm and well dispersion in biologically compatible SiO2 matrix. The superparamagnetism and hyperthermic property of SiO2 coated γ-Fe2O3 nanocomposite powder were discussed in terms of microstructural development in this study

Symplectic Embedding of a Massive Vector-Tensor Theory with Topological Coupling

In the symplectic Lagrangian framework we newly embed an irreducible massive vector-tensor theory into a gauge invariant system, which has become reducible, by extending the configuration space to include an additional pair of scalar and vector fields, which give the desired Wess-Zumino action. A comparision with the BFT Hamiltonian embedding approach is also done.Comment: LaTeX file, 23 page

Staged Surgery for Chronic Primary Aortoduodenal Fistula in a Septic Patient

Aortoenteric fistula is one of the most challenging problems that confront the vascular surgeons. Controversy remains over the optimal treatment because of the continued publication of series with high mortality, amputation, and aortic disruption rates. A positive preoperative blood culture is the best predictor of mortality with increased amputation rates due to infection of the extra-anatomic bypass. Therefore, in selected cases with sepsis, a prudent management protocol is required. We report a 68-yr-old male presenting with a chronic primary aortoduodenal fistula extensively involving the duodenum and Gram-negative sepsis. We planned a staged operation. Initially, an emergency laparotomy and control of the aorta allowed stabilization of the patient, identification of the fistula, and direct in situ placement of the prosthetic graft followed by an en bloc resection of the aneurysm and the surrounding structures. After he recovered from sepsis and had been stabilized, a staged extra-anatomic bypass followed by transabdominal removal of the temporarily placed graft was done. This management plan will allow the highest success rate and may be a prudent management protocol for these difficult cases