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In P2P file sharing systems over mobile cellular networks, the bottleneck of file transfer speed is usually the downlink bandwidth of the receiver rather than the uplink bandwidth of the senders. In this paper we consider the impact of downlink bandwidth limitation on file transfer speed and propose two novel peer selection algorithms named DBaT-B and DBaT-N, which are designed for two different cases of the requesting peer's demand respectively. Our algorithms take the requesting peer's downlink bandwidth as the target of the sum of the selected peers' uplink bandwidth. To ensure load balance on cells, they will first choose a cell with the lowest traffic load before choosing each peer. We also provide a Fuzzy Cognitive Map that can be used to estimate peers' service ability in P2P systems over mobile cellular networks. Simulation results show that in respective cases DBaT-B and DBaT-N can both achieve much better load balance on cells than some traditional algorithms while ensuring favorable file transfer speed.

We propose a novel segmentation algorithm TSESS and a novel chunk scheduling algorithm TSESCS for SVC based P2P streaming systems. TSESS splits each layer into equal sized chunks and tags each chunk with a time-stamp. TSESCS is based on TSESS and adopts two scheduling windows with adaptive strategies. Compared with traditional segmentation algorithm and chunk scheduling algorithms, our TSESS and TSESCS algorithms can achieve better video quality on clients in heterogeneous network environments.

Cloud based datacenters provide on demand services and resources, both transparently and cost effectively. These services and applications are typically hosted and run on the servers located in interconnected datacenters. The task or application request from users can be abstracted as a virtual network (VN) request. How to efficiently accommodate VN requests by mapping them onto the substrate network is a challenging problem. Current research only considers static VN requests, where the VN request and the demand for resources is fixed and does not change over time. However, most of the application requests submitted to datacenters present dynamic changing characteristics. In this paper, we address the issue of how to optimally reconfigure and map an existing VN while this VN request changes. As the VN provisioning problem is NP-hard, we propose heuristic algorithms for solving it efficiently. We evaluate the performance and effectiveness our algorithms by conducting simulations on realistic network. The simulation results show that our approach solves this problem efficiently and performs well than existing approaches.

Due to the characteristics of the DCF model in 802.11 and P2P users' requirements of both downloading and uploading, P2P traffic frequently causes congestion in WLAN. However, traditional P2P cache cannot alleviates the congestion caused by P2P traffic in WLAN effectively. In this paper, we propose a novel solution called bidirectional cache for this problem. A bidirectional cache which contains a reverse cache as well as a forward cache can be deployed at the AC of a WLAN. Being a novel design, the reverse cache can cache release the uplink bandwidth resource at each AP can be and the congestion can be alleviated effectively. Meanwhile, the forward cache can still act as the traditional P2P cache to reduce the cross domain traffic. Simulation results show that, compared with traditional P2P cache, our bidirectional cache can shorten the file transfer time of P2P applications by at least 42% and improve the throughput of the other Internet applications by at least 28%.

In the cloud computing paradigm users access applications/services hosted and run on virtual machines in interconnected datacenters. Applications from the same user may need to interact and change data or information, thus, we may abstract the applications/services request from same user as a virtual network (VN). To improve performance and resource efficiency, it is critical that the VN request be optimally provisioned given the current resource state of the datacenters. However, all of the existing research about optimal VN provisioning conducted for deterministic services. In this work, we formulate the problem of optimal provisioning for elastic service oriented VN request as a mixed integer programming (MIP) model with the objective of maximizing the total revenue of infrastructure provider (InP), and propose a genetic algorithm based heuristic (GAH) algorithm for addressing the optimal provisioning for virtual network request with un-splittable flow (OPVNUF) and optimal provisioning for virtual network request with splittable flow (OPVNSF) problems of elastic services. We demonstrate the effectiveness of our approach for improving the total revenue, by conducting extensive simulations on real substrate network.

In the paradigm of cloud computing, multiple users can share the cloud infrastructure resources. The application or service requests from a user can be abstracted as a virtual network (VN) request and submitted to the cloud-based data centers. How to map a virtual network onto the cloud infrastructure network is a challenging issue in cloud resource provisioning. Current researches about virtual network mapping problem mainly focus on resource efficiency, which can be classified into resource efficient VN mapping or cost efficient VN mapping. However, the amount of power or energy consumed by data centers takes a large part of all of the power consumption. This may not only leads to a higher expenditure on the operation of data centers but also contribute to carbon emissions and the greenhouse effect. In this work we study the problem of power efficient virtual network mapping and propose a framework and algorithm for solving this problem. The simulation results show that our approach performs well.

Given a randomly drawn sample, calibration weighting can provide double protection against the selection bias resulting from unit nonresponse. This means that if either an assumed linear prediction model or an implied unit selection model holds, the resulting estimator will be asymptotically unbiased in some sense. The functional form of the selection model when using linear alibration adjustment is dubious. We discuss an alternative, nonlinear calibration-weighting procedure and software that can, among other things, implicitly estimate a logistic-response model., Survey Research Methods, Vol 6, No 2 (2012)

Infant birth weight and gestational age are two important variables in obstetric research. The primary measure of gestational age used in US birth data is based on a mother's recall of her last menstrual period, which has been shown to introduce random or systematic errors. To mitigate some of those errors, Oja et al., Platt et al., and Tentoni et al. estimated the probabilities of gestational ages being misreported under the assumption that the distribution of infant birth weights for a true gestational age is approximately Gaussian. From this assumption, Oja et al. fitted a three-component mixture model, and Tentoni et al. and Platt et al. fitted two-component mixture models. We build on their methods and develop a Bayesian mixture model. We then extend our methods using reversible jump Markov chain Monte Carlo to incorporate the uncertainty in the number of components in the model. We conduct simulation studies and apply our methods to singleton births with reported gestational ages of 23–32 weeks using 2001–2008 US birth data. Results show that a three-component mixture model fits the birth data better for gestational ages reported as 25 weeks or less; and a two-component mixture model fits better for the higher gestational ages. Under the assumption that our Bayesian mixture models are appropriate for US birth data, our research provides useful statistical tools to identify records with implausible gestational ages, and the techniques can be used in part of a multiple-imputation procedure for missing and implausible gestational ages. Published 2012. This article is a US Government work and is in the public domain in the USA.

We have extended the method of modulated excitation, a small perturbation kinetic method, to study ligand binding and conformational change of hemoglobin tetramers with a single ligand bound. To restrict the excitation to the first ligand, only 1% of the hemes have bound CO, and the remainder are kept unliganded. A detailed theory is presented which agrees well with the experimental observations. This method of observing ligand recombination also provides a novel and simple method for determination of hemoglobin concentration. Additional relaxation processes are also observed. By fitting independently determined spectra to the spectra associated with the relaxations, these processes are assigned as thermal excitation and thermally driven protonation/deprotonation reactions. These added relaxations arise from the deoxy-Hb portion of the samples, and demonstrate that modulated excitation can be used effectively for temperature perturbation in the absence of photodissociation. The spectra observed are not well described by the spectra of allosteric change, however, and we conclude that there is no significant mixing of quaternary states at the first ligation step. In an appendix we present a derivation of the particular features seen in thermally modulated protonation reactions.

The objective of this study was to evaluate the usefulness of covariates in identifying birth records with implausible values of gestational age. Birthweight distributions for births with early reported gestational ages are markedly bimodal, suggesting a mixture of two distributions. Most births form a normal-shaped left-hand (primary) distribution and a smaller number form the right-hand (secondary) distribution. The births in the secondary distribution are thought to have gestational age mistakenly reported. Prior work has found that births in the secondary distribution are at higher risk of poor outcomes than those in the primary distribution. Using 2002 US Natality data for gestational ages 26-35 weeks, we fit normal mixture models to birthweight with and without covariates (maternal race, education, parity, age, region of the country, prenatal care initiation) by reported gestational age. Additional models were stratified by infant sex. This approach allowed for the relationship between the covariates and birthweight to differ between the components. Mixture models fit reasonably well for reported gestational ages33 weeks, but not for later weeks. Counter to the hypothesis, results were similar for models with and without covariates or stratification or both, although stratified models without covariates predicted slightly more girls and slightly fewer boys in the secondary distribution than did the corresponding unstratified models. For reported gestational ages33 weeks, predictions from the four sets of models were highly correlated and predictions were similar for subgroups defined by the clinical estimates of gestational age and other covariates. For births with reported gestational ages of 29 or more weeks, the proportion in the secondary distribution exceeded 30%, although this varied by maternal characteristics. The use of covariates and stratification complicated model fitting without materially improving identification of implausible gestational age values, supporting inferences from prior studies using data 'cleaned' without consideration of maternal or infant characteristics.

The inertial navigation system (INS) computer is a key part in the inertial navigation application. Traditional PC104 computer is of many disadvantages such as fixed board layout and large power dissipation, which makes the system impossible to integrate the functions of signal collecting and navigation computing for reducing the power dissipation and size of board. In this paper, a new INS computer is designed using DSP TMS320C6713 and FPGA XC3S400AN. The computer integrates the signal collecting work by employing pulse subdivision method to avoid ±1 quantization error. Experimental results show that the new INS computer gets good performance on signal collecting (RMS of 10−3) and inertial navigation computing, brings decreased power dissipation (1.5W) as well, which makes it useful in INS application.

The frequency stability is of great importance to DILAG's performance. Based on physical principle of frequency stabilizing, a fuzzy PID controller is designed by combined fuzzy control with conventional PID control. Simulated and experimental results show that the fuzzy PID controller is superior to the conventional PID controller in dynamic steady performance, and the fuzzy PID controller features stronger null stability.

We propose a Mixed Sharing Auxiliary Graph (MSAG) for dynamic traffic grooming in heterogeneous WDM mesh networks. Based on MSAG model, a novel heuristic named BLSW-ILMS (Backup LSP Shared Working Lightpath with Inter-layer Mixed Sharing) is proposed. Simulation results show that the proposed algorithm can efficiently decrease the blocking probability (BP).

Topological dynamics and periodicity are two of the major differences between LEO satellite networks and terrestrial networks. In this work, we first propose MAPSS (Method to Analyze Periodicity of Satellite System) to obtain the system period of satellite networks based on spectral analysis. Then the topological dynamics of satellite networks, including the number of snapshots in one system period, is characterized by using this new method. Our method could be used in the development of routing algorithms as well as the design of satellite constellation.

We propose a Mixed Sharing Auxiliary Graph (MSAG) for dynamic traffic grooming in heterogeneous WDM mesh networks. Based on MSAG model, a novel heuristic named BLSW-ILMS (Backup LSP Shared Working Lightpath with Inter-layer Mixed Sharing) is proposed. Simulation results show that the proposed algorithm can efficiently decrease the blocking probability.

Intraplantar injection of bee venom (BV) produces persistent spontaneous nociception (PSN), hyperalgesia, and inflammatory swelling of the injected paw. The present study was designed to determine the roles of peripheral metabotropic glutamate receptors (mGluRs) in BV-induced nociception and inflammation. We determined the effects of the group I mGluR antagonist AIDA, the group II mGluR agonist ADPC, and the group III mGluR agonist L-AP4 on BV-induced PSN, mechanical hyperalgesia, and inflammatory swelling. Pretreatment with intraplantar injections of AIDA, ADPC or L-AP4 at different doses significantly inhibited BV-induced PSN over the 1-hour observational period. The inhibitory effects of ADPC and L-AP4 were completely abolished by pretreatment with the group II mGluR antagonist LY341495 and the group III mGluR antagonist MSOP, respectively. Pretreatment with ADPC prevented the BV-induced decrease in paw-withdrawal mechanical threshold (PWMT) in a dose-dependent manner, while pretreatment with AIDA or L-AP4 had no effect. The antihyperalgesic effect of ADPC was completely abolished by pretreatment with LY341495. Pretreatment with AIDA, ADPC or L-AP4 at different doses had no effect on the BV-induced increase in the paw volume (PV), a measurement of inflammatory swelling. All contralateral drug treatments at the highest doses had no effect on BV-induced PSN, decreases in PWMT or increases in PV, eliminating the possibility of drug-induced systemic effects. These data suggest that the activation of mGluRs in the periphery may play a differential role in BV-induced nociception and inflammation. Perspective The present study demonstrated that the intraplantar injection of antagonists or agonists of different mGluRs produced differential effects on bee venom-induced persistent spontaneous nociception and mechanical hyperalgesia. However, no effects on inflammation were observed, suggesting that mGluRs in the periphery have differential roles. Thus, therapies specifically targeting metabotropic glutamate receptors may improve the treatment of patients with persistent spontaneous nociception and hyperalgesia.

Establishing thrombosis-resistant surface is crucial to develop tissue-engineered small diameter vascular grafts for arterial reconstructive procedures. The objective of this study was to evaluate the stability and anti-coagulation properties of heparin covalently linked to decellularized porcine carotid arteries. Cellular components of porcine carotid arteries were completely removed with chemical and physical means. Heparin was covalently linked to the decellularized vessels by a chemical reaction of the carboxyl end of amino acids with hydroxylamine sulphate salt and heparin-EDC. Bound heparin contents were measured by quantitative colorimetric assay of toluidine blue staining. The average content of heparin in treated vessels was 35.6 +/- 11.6 mg/cm(2) tissue, which represented 6.21 +/- 2.03 UPS heparin/cm(2) tissue. The stability of heparin linkage was tested by incubating the heparin-linked vessels either in PBS at 37 degrees C or in 70% alcohol at room temperature up to 21 days, showing no significant reduction of heparin content. Anti-coagulation property of bound heparin was determined with a clotting time assay using fresh dog blood. Standardized small pieces of non-heparin-bound vessels were clotted in fresh dog blood within 10 min., whereas all heparin-bound vessels did not form clot during 1-hr observation. In vivo platelet deposition of the vessel was determined with a baboon model of the femoral arteriovenous external shunt and (111)Indium labelling of platelets. There were 1.38 +/- 0.07 x 10(9) and 0.64 +/- 0.11 x 10(9) baboon platelets deposited on the control and heparin-linked vessels, respectively, at 60 min. These data demonstrate that covalent linkage of heparin provides an effective and stable anti-coagulation surface of decellularized porcine carotid arteries. This study may suggest a new strategy to develop tissue-engineered biological vascular grafts, which could be used for human coronary or low extremity artery bypasses.

This paper focuses on minimizing the capacity of DiffServ/MPLS networks taking into account two widely deployed bandwidth constraint models: the maximum allocation model (MAM) and the Russion doll model (RDM). With the given physical network and traffic demands, by optimizing Label Switched Paths (LSPs) resource allocation, route distribution, our designs aim at minimizing the link capacity of the total network. The optimization problems are formulated as integer linear programming (ILP) models first, and then, since the ILP formulation is not adapted for large-scale network, two novel fast algorithms are proposed. Numerous simulation results for a variety of networks indicate that the performances of our proposed algorithms are close to the optimal results.

In this paper, we propose an effective upgrading algorithm in incremental planning for optical networks. This algorithm integrates making full use of existent available resource with upgrading capacity. Our objective is to minimize the newly added resource in the network. The Integer Linear Programming (ILP) formulation is presented. Since the ILP formulation is not adapted for large-scale network, a novel fast heuristic algorithm called Minimal Upgrading Resource (MUR) is proposed and evaluated. Computer simulation results show the MUR can achieve the performance near to the ILP results, and performs better than other two proposed approaches.

Objective of this study was to develop a novel in vitro artery culture system to study vascular smooth muscle cell (SMC) proliferation of porcine carotid arteries in response to injury, basic fibroblast growth factor (FGF2), and FGF2 conjugated with cytotoxin saporin (SAP). Perfusion-cultured porcine carotid arteries remained contractile in response to norepinephrine and relaxant to acetylcholine for up to 96 hours. SMC proliferation of cultured arteries was detected by bromodeoxyuridine incorporation in both non-injured and balloon-injured arteries. In the inner layer of the vessel wall near the lumen, SMC proliferation were less than 10% in uninjured vessels, 66% in injured vessels, 80% in injured vessels with FGF2 treatment, and 5% in injured vessels with treatment of FGF2-SAP. Thus, the cultured porcine carotid arteries were viable; and the injury stimulated SMC proliferation, which was significantly enhanced by FGF2 and inhibited by FGF2-SAP.

In terrestrial-satellite hybrid networks, traditional TCP performance degrades a lot due to long propagation delays and high bit error rates link. Performance enhancing proxy(PEP) can shorten round trip time loop time and Peach can enhance the performance over high bit error rates link. In this paper, we propose a new scheme that combines PEP and TCP Peach for terrestrial-satellite hybrid networks. The scheme could reduce the negative impact on performance (in terms of throughput). To obtain an analysis result, we also introduce a mathematic model for our PEP. The analysis and simulation results demonstrate that our scheme could significantly improve the network performance than traditional TCP protocols.

Intraplantar injection of bee venom (BV) produces persistent spontaneous nociception (PSN) and hyperalgesia, as well as obvious inflammatory swelling, in the paws of injected rats. The present study was designed to determine the peripheral roles of mitogen-activated protein kinase (MAPK) signal transduction pathways in BV-induced nociception and inflammation. We examined the effect of intraplantar injection of an ERK1/2 inhibitor, PD98059, and a p38 inhibitor, SB202190, on BV-induced PSN, mechanical hyperalgesia, and inflammatory swelling. We found that (1) pretreatment with SB202190 (0.1 to 10 μg) had no effect on BV-induced PSN, whereas pretreatment with PD98059 (0.1 to 100 μg) produced a significant and dose-dependent inhibition of BV-induced PSN; (2) pretreatment with PD98059 (0.1 to 100 μg) had no effect on BV-induced decreases in paw withdrawal mechanical threshold (PWMT), while pretreatment with SB202190 (0.1 to 10 μg) produced an obvious prevention of the BV-induced decrease in PWMT; and (3) pretreatment with PD98059 (0.1 to 100 μg) had no effect on BV-induced increase in paw volume (PV), whereas pretreatment with SB202190 (0.1 to 10 μg) produced a dose-related inhibition of BV-induced increases in PV. No contralateral drug treatments, even at the highest dose, had any effect on BV-induced PSN, PWMT or PV, ruling out the systemic effect of these drugs. These results suggest that peripheral MAPK signal transduction pathways may play differential roles in bee venom-induced nociception and inflammation. Targeting specific peripheral MAPKs might prove effective in the treatment of persistent pain and inflammation. Perspective The present article showed that intraplantar injection of different MAPK inhibitors produced differential effects on bee venom-induced nociception and inflammation, suggesting that the peripheral MAPK signal transduction pathways have differential roles. Targeting specific peripheral MAPKs might prove effective in the treatment of persistent pain and inflammation.

Membrane proteins fulfill a wide range of central functions in the cell, but their structure determination remains one of the great challenges in structural biology. The heterologous overexpression is a demanding task. Here, we provide an overview of recent advance to heterologous expression and purification of membrane protein from Mycobacterium tuberculosis, whose membrane proteins represent the majority of the new potential drug targets in this bacillus, which is ranked as the number1 cause of infectious disease mortality in the world. A detailed structural and functional understanding of the membranes protein of Mycobacterium tuberculosis will be critical both for an understanding of the biology of infection and for the rational development of novel therapeutics. The procedures for functional expression followed by purification of membranes protein are reviewed here together with nonfunctional expression in inclusion bodies and subsequent refolding to produce functional proteins. The new expression systems, new approaches to soluble expression of recombinant proteins, new methods for membrane protein folding in vitro and new purification technology will provide a basis for choosing the best expression and purification protocol for a given membrane protein. The goal of this review is to aid researchers in the choice of a suitable expression system for their favourite proteins and make overproduction of functional membrane proteins becomes easier.

To investigate the expression of Angiotensin II type 1 receptor (AT1R) in tissue and cell lines of squamous cervical carcinomas and its clinical significance, and to explore the molecular mechamisms of angiotensin II and AT1R activity in the process of cervical carcinogenesis.(1) The levels of AT1R mRNA were examined by quantitative reverse transcriptase-polymerase chain reaction( RT-PCR) in paraffin-embedded tissues from 35 cases of cervical squamous cell carcinoma, 15 cases of cervical intraepithelial neoplasia (CIN), and 15 cases of normal cervix, and in Siha and C33a cells. The expression of AT1R protein in 65 specimens of cervix tissue sections was evaluated by immunohistochemistry. The corelation between the expressions of AT1R and its clinicopathologic features was analyzed accordingly. (2) After the Siha and C33a cells were treated at different concentrations of Angiotensin II (0, 10(-10) mol/L, 10(-9) mol/L, 10(-8) mol/L, 10(-7) mol/L, 10(-6) mol/L, 10(-5) mol/L) for different time in culture, the cell proliferation was determined by methylthiazolyl tetrazolium (MTT) assay. The vascular endothelial growth factor (VEGF) expression was examined by enzyme-linked immuno-absordent assay (ELISA).(1) AT1R mRNA expression was detected in the two cervix cancer cell lines. The positive rate of ATIR mRNA was 77.1%, 40.0% and 0, respectively, in squamous cell carcinomas, cervical intraepithelial neoplasia and normal cervical tissues, while their mRNA quantities were 0.3863 +/- 0.041, 0.0768 +/- 0.035 and 0, respectively. There was statistically a significant difference between them (P0.01). The average staining intensity of AT1R protein was stronger in invasive carcinoma cells than that in dysplasia tissues and normal ones (P0.01). Among 65 cases of squamous cell carcinomas, the expressions of AT1R mRNA and protein increased with pathological grading (P0.05), while it was neither correlated with clinical stage nor pelvic lymph node metastasis (P0.05). The level of AT1R protein expression corresponded to that of its mRNA. (2) Angiotensin II promoted the cell growth of cervical cancer cell lines Siha and C33a and induced secretion of VEGF from cells in a dose-dependent manner (P0.01), and the expression of VEGF was reversed by the addition of valsatan (an antagonist of angiotensin II type 1 receptor) (P0.01).Angiotensin II is involved in the progression of cervical carcinoma, since it may increase the proliferation activity of cancer cells, induce secretion of VEGF through AT1R synchronously, and results in an increase of angiogenesis in tumors. It suggests that use of AT1R antagonists may be an useful therapeutic strategy for cervical carcinoma.

Scalability is one of the key issues of the researches on next-generation Packet Switching Fabrics (PSF). The torus network becomes a promising technology for next-generation PSF, since it has good scalability as well as high capacity and reliability. In this paper, the principles on how to determine the values of critical design parameters for constructing PSF of Torus topology (PSF-T) are discussed. Then a modular switching subnetwork that employs the torus network technology, Configurable Board (CB), is proposed. A scheme to construct scalable PSF-T with CB modules is also given. The number of ports and the capacity of the PSF can grow smoothly up to hundreds of times, and its performance does not degrade during scaling. Simulation results are presented to show the validity of our scheme.

The clustering Algorithm is a kind of key technique used to reduce energy consumption. It can increase the scalability and lifetime of the networks. Energy-efficient clustering algorithm should be designed for the characteristic of heterogeneous wireless sensor networks. We propose and evaluate a new cross-layer energy efficient clustering (CLEEC) algorithm for heterogeneous wireless sensor networks with renewable energy source. In CLEEC, the cluster heads are elected by probabilities based on cross-layer optimal estimation, considering energy replenishment. The cross-layer optimal estimation uses cross-layer information, such as energy and replenishment rate, to theoretically compute the election probabilities. Finally, the simulation results demonstrate that our clustering approach outperforms current important clustering algorithms in the efficiency of prolonging the network lifetime.

Hyperhomocysteinemia (HHcy) is a significant and independent risk factor for cardiovascular disease (CVD) and the underlying mechanism is unclear. We and others have reported that homocysteine (Hcy) is inversely correlated with plasma high-density lipoprotein cholesterol (HDL-C) and apolipoprotein AI (apoA-I) in patients with coronary heart disease (CHD). We confirmed this negative correlation in mice with targeted deletions of the genes for apolipoprotein E (apoE) and cystathionine beta-synthase (CBS). Severe HHcy (plasma Hcy 210 micromol/L) accelerates spontaneous arthrosclerosis in the CBS(-/-)/apoE(-/-) mice, reduces the concentration of circulating HDL, apoA-I, and large HDL particles, inhibits HDL function, and enhances HDL-C clearance. We have demonstrated further that Hcy (0.5-2 mmol/L) reduces apoA-I protein synthesis and secretion, but not RNA transcription in mouse primary hepatocytes. A different mechanism was proposed based on studies using the HepG2 cells showing that Hcy (5-10 mmol/L) inhibits apoA-I transcription via peroxisome proliferator-activated receptor-alpha (PPARalpha)-inhibition-dependent and -independent mechanisms. These studies suggest that Hcy-induced HDL-C and apoA-I inhibition represent a novel mechanism by which Hcy induces atherosclerotic CVD.

This paper considers jointly optimal design of cross-layer congestion control and opportunistic scheduling. The cross-layer design aims to maximize the system performance, while guaranteeing multiple QoS (quality of service) constraints for wireless data networks accommodating multiclass services with different quality requirements. We first propose a channel and queue adaptive congestion controller (CQACC) to control the data generation rate. Then, we propose a queue aware multiple QoS opportunistic scheduling (QAMQOS) scheme to allocate the resources. In this paper, we show that combination of QAMQOS and CQACC can lead to high system throughput and multiple QoS guarantee.

In this paper, we address the problem of resource allocation with efficiency and quality of service (QoS) support in uplink for a wireless CDMA network supporting real-time (RT) and nonreal-time (NRT) communication services. For RT and NRT users, there are different QoS requirements. We introduce and describe a new scheme, namely the traffic aided uplink opportunistic scheduling (TAUOS). While guaranteeing the different QoS requirements, TAUOS exploits the channel condition to improve the system throughput. In TAUOS, the cross-layer information, file size information, is used to improve the fairness of NRT users. Extensive simulation results show that our scheme can achieve high system throughput in uplink wireless CDMA system, while guaranteeing the QoS requirements.

In this paper, we focus on the problem with the objective to maximize the system performance, while guaranteeing multiple QoS (quality of service) constraints for wireless data networks accommodating multiclass services with different quality requirements. First, we formulate and solve the opportunistic scheduling problem with multiple general long-term QoS constraints. Then, we generalize this problem to include short-term QoS constraints for real-time multimedia users and long-term QoS constraints for non-real-time data users simultaneously in multiclass services networks. Simulation results illustrate that the proposed scheduling schemes guarantee the different QoS constraints, and achieve high system performance.

In this paper, we focus on the problem with the objective to maximize the system performance, while guaranteeing specified QoS constraints for multiple user classes in wireless data networks. First, we propose two opportunistic scheduling algorithms that exploit time-varying channel conditions for the special two-constraint case, and then propose an opportunistic scheduling algorithm for the general case. Simulation results illustrate that the proposed scheduling algorithms guarantee the different constraints, and achieve high system performance that is close to the true optimal value using a known general-purpose optimization package, lingo

In this paper, we study the fundamental problem of allocating the available resources with efficiency and fairness in a wireless CDMA network. In particular, we first introduce an ideal fair scheduling (IFS) scheme. The allocation of resources in IFS is strictly fair. Then we introduce the proportional compensation based fair scheduling (PCFS) algorithm. PCFS distinguishes the services in different application levels. In PCFS, a channel-adaptive resource allocation policy is introduced to improve the system throughput and a compensation model is introduced to achieve fair services. Based on the assignment of PCFS, we propose the traffic aided PCFS (T-PCFS) algorithm that incorporates traffic information into compensation model to achieve better fairness. Extensive simulation results show that our scheme can operate well in wireless CDMA networks.

Objective: Hyperhomocysteinemia (HHcy) is a risk factor for cardiovascular disease and has been reported to inhibit endothelial cell (EC) growth. Notwithstanding, precisely how HHcy regulates EC growth in vivo remains unknown. In this study, we established a mouse model of endothelial injury and reendothelialization and examined the role and mechanism of HHcy in endothelial repair. Methods and results: A mouse model of carotid artery air-dry endothelium denudation and reendothelialization was established and used to evaluate post-injury endothelial repair in mice with the gene deletion of cystathionine-h-synthase (CBS). Moderate and severe HHcy were induced in CBS +/+ and CBS /+ mice through a high-methionine diet. Post-injury reendothelialization, which correlated with increased postinjury neointima formation, was impaired in severe HHcy mice. To elucidate the underlying mechanism, we examined circulating endothelial progenitor cells (EPC) in HHcy mice and studied the effect of homocysteine (Hcy) on proliferation, migration, and adhesion of human umbilical vein endothelial cells (HUVEC). The peripheral EPC population was not significantly altered in HHcy mice. Hcy had a profound inhibitory effect on EC proliferation and migration at physiologically relevant concentrations and inhibited EC adhesion at concentrations of 200 AM and higher. Conclusion: We have established a convenient and accurate mouse model of carotid injury in which the reendothelialization process can be precisely quantified. In addition, we have observed impaired reendothelialization and increased neointimal formation in severe HHcy mice. The capacity of Hcy to inhibit proliferation and migration of EC may be responsible for impaired reendothelialization and contribute to arteriosclerosis in HHcy.

Fair queuing has long been a popular paradigm for providing bounded delay channel access and separation between users in wired networks. However, adapting fair queuing to the wireless domain is not a trivial task because of the unique problems in wireless channels such as location dependent and bursty channel error. In this paper, we incorporate traffic information into wireless fair scheduling using compensation scheme. In particular, we first establish general properties for fair scheduling using proportional compensation scheme in CDMA cellular networks. It distinguishes the services in different application levels. A compensation model and a reallocation method in the scheme were introduced to achieve wireless fair services. Then, we develop a new traffic aided fair scheduling scheme based on compensation model by making use of file size information. Extensive simulation results show that our scheme can operate well in CDMA cellular networks.

We first discuss the need for computational electromagnetics (CEM) in high-frequency IC design. We then review recent advances in CEM, present chip design challenges to CEM analysis, and analyze the shortcomings of current CEM methodology. We then emphasize the importance of chip-design-driven CEM development, and finally present some promising full-wave electromagnetic-based solutions that can achieve full-chip analysis and design.

To investigate the effect of Tauroursodeoxycholic acid (TUDCA) on Taurodeoxycholic acid (TDCA)-induced HepG2 cell apoptosis and to clarify the molecular mechanism of its anti-apoptosis effect of TUDCA.Morphologic evaluation of apoptotic cells was performed by Hoechst 33258 staining and electron microscope. DNA fragment was detected by electrophoresis on 1.5% agarose gels. Apoptosis rate was measured by flow cytometry using PI dye. Following incubation of HepG2 cells either with TDCA alone, or coincubation with TUDCA and TDCA, the releasing level of cytochrome c from mitochondria into cytosol was determined by western blot, also the activity of caspase-3, 8, 9.Incubating the cells with 400 micromol/L TDCA for 12 h induced the cells apoptosis significantly. The apoptotic rate decreased from 50.35% +/- 2.20% to 13.78% +/- 0.84% after coincubation with TUDCA, and this anti-apoptotic effect of TUDCA was confirmed by morphological and DNA ladder detection. TUDCA significantly inhibited the release of cytochrome C from mitochondria into cytosol, and the activity of caspase-9, 3 (tor = 13.00, P0.01), especially at 12 h, caspase-3 activity decreased by 54.9% (t = 16.88, P0.01) and 52.5%, however it had no obvious effect on the activity of caspase-8 (t = 1.94, P0.05).TUDCA prevents HepG2 cells apoptosis induced by TDCA through modulating mitochondrial membrane stability, inhibiting the release of cytochrome c and the activation of procaspase-9 and 3. Anti-apoptotic mechanism of TUDCA may be considered to be one of the most important reasons that TUDCA exerts significant efficacy in the treatment of cholestatic liver diseases.

AIM:To study the effect of hepatocyte apoptosis and necrosis induced by TNF-alpha on the pathogenesis of acute severe hepatitis (ASH).METHODS:The model of ASH was prepared in D-galactosamine (GalN) sensitized BALB/c mice by injection of either endotoxin (ET) or tumor necrosis factor-alpha(TNF-alpha. Morphological changes of apoptotic hepatocytes were studied by both light and electron microscope and in site end labeling method (ISEL). Molecular biological changes of DNA ladder were observed by electrophoresis of extract from liver tissues. Biochemical changes were measured by alanine aminotransferase (ALT), aspartic aminotransferase (AST) and TNF-alpha. The relation between apoptosis and necrosis was evaluated simultaneously.RESULTS:The sequence of hepatocyte apoptosis, necrosis, and final death from ASH was observed both in GalN/ET and GalN/TNF-alpha group. Apoptosis was prominent at 3.5h and 6h after injection of inducer, while necrosis became dominant at 9h after challenge. The appearance of apoptosis was earlier in GalN/TNF-alpha group than that in GalN/ET group. Pretreatment of mice with antiTNF IgG1 may completely prevent the liver injury induced by GalN/ET.CONCLUSION:TNF-alpha can cause liver amage by inducing hepatic apoptosis and necrosis in mice with endotoxemia.

The Combitube ® is a relatively new device used for blind insertion emergency intubation. We report a case of successful Combitube ® treatment of an acute respiratory arrest secondary to an acute asthma exacerbation. An advanced EMT-II (National Park Service Parkmedic) utilized this device. Our review of the literature revealed no reported cases of an advanced EMT-II, nor any other cases, using the Combitube ® in asthma-related respiratory failure.

We have developed a photolytic method to determine the concentration of reactive hemes in a solution in the presence of a trace amount of CO. By measurement of the bimolecular rate of CO binding, and by calibration of the rate constant under equivalent conditions, the concentration of the reactive hemes can be determined. In a solution of sickle hemoglobin, the molecules in the gel contribute negligibly to the recombination rate, allowing the concentration of the molecules in the solution phase to be determined. To optimize signal to noise, modulated excitation methods were employed, although the method could also be used with pulse techniques and suitable signal averaging. Because the optical method employs a microspectrophotometer, only a few microliters of concentrated Hb solution is required to reproduce the entire temperature dependence of the solubility previously determined by centrifugation using milliliter quantities of solutions of the same concentration. This should be especially useful for studies of site-directed mutants, and we present results obtained on one such HbS in which Leu 88 beta has been replaced by Ala. The free energy difference in the polymerization of the Leu 88 beta double mutant is consistent with known differences in the amino acid hydrophobicities. The calibration required for these experiments also provides an excellent determination of the activation energy for binding the first CO to deoxy Hb.

IMU rotation of an inertial navigation system (INS) can bound the free propagation of the INS error introduced by the drifts of inertial sensors. The rotation scheme of the IMU will directly affect the accuracy, structure and costs of the system. A reasonable rotation scheme should remove most of the system errors arising from the drifts of the inertial sensors, and at the same time, should not introduce other additional errors. First, this paper discusses the design and analysis approach of the rotation scheme based on the error propagation equations of the INS. Then, a conventional 8-position rotation scheme is analyzed for the applications of the optical gyro INS, and its drawbacks are discussed in detail. Following these, an improved 8-position rotation scheme and a novel 16-position rotation scheme are proposed for the optical gyro INS, and their merits are also discussed. Simulation results have shown that the 16-position rotation scheme, which can compensate not only the drifts but also the scale factor errors and the misalignment errors of the inertial sensors, is the best rotation scheme and can be used as a practical solution to compensate the drifts of the inertial sensors in the rotational INS.