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Single-crystal PbTiO 3 (PT) nanorods have been synthesized by annealing PT nanocrystals in NaCl flux. The as-prepared PT nanorods are straight, with diameters of 50–80 nm and lengths of a few micrometers. The nanorods are in tetragonal crystal structure with lattice constants a = b = 3.926 A and c = 3.963 A. All the Raman modes of the PT nanorods have been indexed and the soften behavior of mode E(1TO) was observed, implying the weakening of ferroelectricity. The formation of the nanorods has also been discussed.

This paper presents a new channel assignment scheme that efficiently improves the spatial frequency–spectrum reuse in a wireless network with heterogeneous demands, in which the cells are partitioned into a lot of clusters. Since the channel demands of each cell are different, this scheme adopts two stages to effectively assign channels. In the first stage, the cluster-based scheme allocates a number of channels to the cells of each cluster for satisfying the requirement of co-channel reuse. The channel demand of majority cells will be satisfied in this stage. In the second stage, when the channel requirement of most cells has been fulfilled, the tree-based assignment scheme allocates channels for the minority cells, which are still lacking of channels. Simulation results showed that the proposed scheme is superior to the previous schemes. Copyright © 2005 John Wiley & Sons, Ltd.

Due to the property of low propagation delay, LEO (Leo Earth Orbit) satellite network is an indispensable solution for providing a global coverage and multimedia communication. However, since the LEO satellites move very fast in orbits, to offer a smooth handover is regarded as the most significant service feature. In this paper, an effective handover management is proposed. The proposed scheme is based on fuzzy logic decision to efficiently determine handover and considers three important parameters, including blocking rate, dropping rate, and bandwidth utilization. From the simulation results, this scheme can achieve the higher bandwidth utilization, the lower new call blocking rate, and the lower handover call dropping rate.

In a typical distributed computing system (DCS), nodes consist of processing elements, memory units, shared resources, data files, and programs. For a distributed application, programs and data files are distributed among many processing elements that may exchange data and control information via communication link. The reliability of DCS can be expressed by the analysis of distributed program reliability (DPR) and distributed system reliability (DSR). In this paper, two reliability measures are introduced which are Markov-chain distributed program reliability (MDPR) and Markov-chain distributed system reliability (MDSR) to accurately model the reliability of DCS. A discrete time Markov chain with one absorbing state is constructed for this problem. The transition probability matrix is employed to represent the transition probability from one state to another state in a unit of time. In addition to mathematical method to evaluate the MDPR and MDSR, a simulation result is also presented to prove its correction.

In this paper, an effective flow control scheme, modified explicit rate indication for congestion avoidance (MERICA), is proposed to adaptively release congestion and enhance throughput for available bit rate (ABR) services in asynchronous transfer mode (ATM) networks. The proposed scheme mainly employs thresholds to determine the traffic status. Whenever the traffic status is changed, the switch will immediately inform the source of the new allowed data rate through the resource management (RM) cell in order to regulate the ABR traffic. For efficiently deriving thresholds, a Markov chain model is developed to precisely describe the behavior of the traffic pattern in ATM networks. Moreover, an algorithm is proposed to efficiently solve the thresholds from the Markov chain model under the time complexity of O(N). Finally, a simulation model is presented to investigate the performance. From the simulation results, the proposed scheme can obtain lower loss rate and higher utilization than other methods.

For analyzing the composite right/left-handed (CRLH) transmission line (TL) problems, an efficient unconditionally stable (US) finite-difference time-domain method is proposed in the letter. First, based on Kirchhoff's voltage law and Kirchhoff's current law, the CRLH TL equations are derived and rewritten in matrix form. Then, by adopting the Crank-Nicolson time split technique, and carrying out some transformations to achieve an equivalent formulation, the US scheme for the implementation of the CRLH TL equations can be obtained. Two numerical examples are used to validate the efficiency and accuracy of the proposed method in analyzing a CRLH TL and pure left-handed TL.

Innovation is crucial to the success of organisations and is a core capability for their long-term survival. Creativity is the starting point of innovation. A number of studies have found that multicultural experiences can stimulate creativity. Nonetheless, the boundary conditions of this influence have yet to be fully elucidated. This study investigated whether one's regulatory focus moderates the relationship between multicultural experience and creativity. We adopted an experimental approach based on the manipulation of multicultural experience and regulatory focus with 120 students (study 1) and 120 executives (study 2) as participants. The results of evaluating their creativity indicated that multicultural experience exerts a significant influence on creativity. Furthermore, regulatory focus moderates the relationship between multicultural experience and creativity. These findings' on multicultural learning and creativity have important implications for human resource management and global learning.

We undertook this meta-analysis to investigate the relationship between revascularization and outcomes after liver transplantation.A literature search was performed using MeSH and key words. The quality of the included studies was assessed using the Jadad Score and the Newcastle-Ottawa Scale. Heterogeneity was evaluated by the χ(2) and I (2) tests. The risk of publication bias was assessed using a funnel plot and Egger's test, and the risk of bias was assessed using a domain-based assessment tool. A sensitivity analysis was conducted by reanalyzing the data using different statistical approaches.Six studies with a total of 467 patients were included. Ischemic-type biliary lesions were significantly reduced in the simultaneous revascularization group compared with the sequential revascularization group (OR = 4.97, 95%CI: 2.45-10.07; P0.00001), and intensive care unit (ICU) days were decreased (MD = 2.00, 95%CI: 0.55-3.45; P = 0.007) in the simultaneous revascularization group. Although warm ischemia time was prolonged in simultaneous revascularization group (MD = -25.84, 95%CI: -29.28-22.40; P0.00001), there were no significant differences in other outcomes between sequential and simultaneous revascularization groups. Assessment of the risk of bias showed that the methods of random sequence generation and blinding might have been a source of bias. The sensitivity analysis strengthened the reliability of the results of this meta-analysis.The results of this study indicate that simultaneous revascularization in liver transplantation may reduce the incidence of ischemic-type biliary lesions and length of stay of patients in the ICU.

Pancreatic cancer (PC) is an aggressive and devastating disease with a poor prognosis. Cisplatin, a commonly used chemotherapeutic agent for solid tumors, is effective as a single agent or in combination with other drugs for the treatment of PC. Previous studies have suggested that Twist and growth differentiation factor 15 (GDF15) are involved in the progression of PC. However, the role of Twist and GDF15 in PC remains to be elucidated. In the present study, the individual effect of and interaction between Twist and GDF15 in PC cell invasion and chemoresistance to cisplatin was examined. Twist and/or GDF15 were stably overexpressed or knocked down in ASPC‑1 and BXPC‑3 human PC cells. Overexpression of Twist in the two cell lines markedly increased GDF15 expression, cell invasion, matrix metalloproteinase‑2 expression/activity and the half maximal inhibitory concentration (IC50) values of cisplatin, which was eradicated by GDF15 knockdown or the selective p38 mitogen‑activated protein kinase (MAPK) inhibitor SB203580 (10 µM). By contrast, Twist knockdown significantly decreased GDF15 expression, cell invasion, matrix metalloproteinase‑2 expression/activity and the IC50 values of cisplatin, which was completely reversed by overexpression of GDF15. In addition, while overexpression and knockdown of Twist increased and decreased p38 MAPK activity, respectively, GDF15 demonstrated no significant effect on p38 MAPK activity in PC cells. In conclusion, the present study, for the first time, to the best of our knowledge, demonstrated that Twist promotes PC cell invasion and cisplatin chemoresistance through inducing GDF15 expression via a p38 MAPK‑dependent mechanism. The present study provides new insights into the molecular mechanisms underlying PC progression and chemoresistance.

The novel title organic salt, 4C5H7N2+·C24H8O84−·8H2O, was obtained from the reaction of perylene-3,4,9,10-tetracarboxylic acid (H4ptca) with 4-aminopyridine (4-ap). The asymmetric unit contains half a perylene-3,4,9,10-tetracarboxylate (ptca4−) anion with twofold symmetry, two 4-aminopyridinium (4-Hap+) cations and four water molecules. Strong N—H...O hydrogen bonds connect each ptca4−anion with four 4-Hap+cations to form a one-dimensional linear chain along the [010] direction, decorated by additional 4-Hap+cations attached by weak N—H...O hydrogen bonds to the ptca4−anions. Intermolecular O—H...O interactions of water molecules with ptca4−and 4-Hap+ions complete the three-dimensional hydrogen-bonding network. From the viewpoint of topology, each ptca4−anion acts as a 16-connected node by hydrogen bonding to six 4-Hap+cations and ten water molecules to yield a highly connected hydrogen-bonding framework. π–π interactions between 4-Hap+cations, and between 4-Hap+cations and ptca4−anions, further stabilize the three-dimensional hydrogen-bonding network.

In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10(-8) M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a potential SERS substrate for molecular detection applications.

Verticillium dahliae Kleb. is a phytopathogenic fungus that causes wilt diseases in hundreds of dicotyledonous plant species. Previous research has demonstrated that the secretome plays an important role in the pathogenicity of V. dahliae. In this study, the specific secreted protein gene (VdSSP1) in highly virulent defoliating V. dahliae strain VDG1 was cloned, and considered to be a secreted protein by signal peptide activity assay. VdSSP1 deletion mutants in VDG1 significantly compromised virulence, and the fungal growth decreased in media with pectin and starch as carbon sources. Pathogenicity and carbon utilization were restored upon complementation of the VdSSP1 deletion strains or low virulence non-defoliating strain VDG2, which lacks VdSSP1. It is indicated that the virulence role of VdSSP1 is associated with plant cell wall degradation. In conclusion, our data suggested that VdSSP1 is a secreted protein that is engaged in the pathogenicity of the highly virulent defoliating V. dahliae.

Assembly of nanowires into ordered macroscopic structures with new functionalities has been a recent focus. In this Letter, we report a new route for ordering hydrophilic Ag nanowires with high aspect ratio by flowing through a glass capillary. The present glass capillary with well-defined silver nanowire films inside can serve as a portable and reusable substrate for surface-enhanced Raman spectroscopy (SERS), which may provide a versatile and promising platform for detecting mixture pollutions. By controlling the flow parameters of nanowire suspensions, initially random Ag nanowires can be aligned to form nanowire arrays with tunable density, forming cambered nanowire films adhered onto the inner wall of the capillary. Compared with the planar ordered Ag nanowire films by the Langmuir-Blodgett (LB) technique, the cambered nanowire films show better SERS performance.

The distribution of He in η-Fe2C has been studied by first-principles calculations. The formation energies of interstitial He and substitutional He (replacing Fe) are 3.76 eV and 3.49 eV, respectively, which are remarkably smaller than those in bcc Fe, indicating that He is more soluble in η-Fe2C than in bcc Fe. The binding potencies of both a substitutional-interstitial He pair (1.28 eV) and a substitutional-substitutional He pair (0.76 eV) are significantly weaker than those in bcc Fe. The binding energy between the two He atoms in an interstitial–interstitial He pair (0.31 eV) is the same as that in bcc Fe, but the diffusion barrier of interstitial He (0.35 eV) is much larger than that in bcc Fe, suggesting that it is more difficult for the interstitial He atom to agglomerate in η-Fe2C than in bcc Fe. Thus, self-trapping of He in η-Fe2C is less powerful than that in bcc Fe. As a consequence, small and dense η-Fe2C particles in ferritic steels might serve as scattered trapping centers for He, slow down He bubble growth at the initial stage, and make the steel more swelling resistant.

In this paper, congestion control schemes are proposed to prevent the network from congestion for ATM (Asynchronous Transfer Mode) networks by controlling the congestion at VC (virtual circuit) and cell levels. At VC level, a bandwidth allocation scheme is performed during the call setup in the form of bandwidth reservation. Call acceptance is decided on the basis of on-line evaluation of traffic utilization. This scheme confines the bandwidth allocation according to the anticipated traffic characteristics and the quality requirements of connected calls. On the other hand, at cell level, an enforcement scheme is proposed to smooth the unexpected traffic from each source during the transmission period. This scheme only allows a cell to be dispatched at the begin of each slot time, thereby regulating cells entering the public network. In addition, several bandwidth enforcement mechanisms and bandwidth allocation methods are presented in order for comparison with the proposed schemes. It shows from the simulation that our schemes perform better than other methods.

To understand the endemic situation of schistosomiasis in Guangdong Province.The surveillance of Oncomelania hupensis snails and infectious sources was carried out in the former endemic areas, and the surveillance data were statistically analyzed from 2004 to 2009 according to the national and provincial surveillance protocols.From 2004 to 2009, an area of 927.45 hm2 was surveyed and no living snails were found, and 287 out of 12 345 young people living in the endemic areas showed serum positive with the DIGFA, but none of schistosomiasis patients were found. A total of 28 766 mobile population were involved in the DIGFA examination, and 417 persons were positive, among them, 52 chronic patients were found, and 6 patients had eggs in their stools. Through the passive surveillance, 281 cases were reported from 2003 to 2009, and 4 acute cases were reported from 2004 (1 case) to 2005 (3 cases). A total of 9 064 head of cattle were surveyed and none of them was infected with Schistosoma japonicum by stool examination.The achievements of schistosomiasis control are solidified in Guangdong Province. However, the risk of schistosomiasis transmission still remains. The surveillance should be continued, especially of imported infectious sources and snails.

This chapter introduces a tightening constraint algorithm combined with the model predictive control within mixed-integer linear programming framework to deal with unmanned rotorcraft path planning problem in a 3-D environment. The bounded-obstacle-boundary uncertainties and moving obstacle uncertainties are considered. The simulation results show the effectiveness and verification of the tightening constraint algorithm. In addition, the simulation also demonstrates that the computation burden has no relation with the environment complexity with this approach.

The number of cooperative sensors to use is a compromise between sensing performance and resources usage efficiency. The definition of the optimal cooperative sensor set is given out firstly and then a greedy selection algorithm for the optimal cooperative sensor set is proposed which can use fewest cooperative sensors to maximize the resources usage efficiency, while still having enough for the sensing performance constraints. Analysis and numerical results illustrate the effectiveness and reliability of the proposed selection algorithm.

The problem of sensor set selection for cooperative spectrum sensing in cognitive radio networks is considered in this paper. The cooperative gain of the newly added cooperative sensor decreases and converges to zero as the number of cooperative sensors increases, but the consumption of system resources grows approximately linearly with the number of cooperative sensors, therefore, the number of cooperative sensors to use is a compromise between sensing performance and resources usage efficiency. A greedy based cooperative sensor set selecting algorithm is proposed which can use a threshold acquired by compromising between sensing performance and resources usage efficiency to select a cooperative sensor set. Numerical results illustrate the effectiveness and reliability of the proposed sensor set selecting algorithm.

Background: Hepatitis B virus (HBV) infection causes large amount of unfolding or false-folding protein accumulation in the endoplasmic reticulum (ER), which in turn induces the expression of glucose-regulated protein 78 (GRP78). The aim in the present study was to analyse the potential association between GRP78 single-nucleotide polymorphisms (SNPs) and the risk of HBV infection.Methods: The associations between seven common GRP78 polymorphisms in the promoter (rs391957, rs17840762, rs17840761, rs11355458) and in the 3' untranslated region (UTR) (rs16927997, rs1140763, rs12009) and possible risk of chronic HBV infection were assessed in a case-control study. 496 cases and 539 individually matched healthy controls were genotyped.Results: Overall, no associations were observed in genotypic analyses. In addition, haplotypes and diplotypes combining those SNPs in the promoter or in the 3' UTR in high linkage disequilibrium (LD) were also not associated with HBV risk.Conclusion: These observations do not support a role for GRP78 polymorphisms in HBV infection in a predominantly Chinese Han population. © 2010 Zhu et al; licensee BioMed Central Ltd., published_or_final_version

To understand the distribution of Angiostrongylus cantonensis foci in Guangdong Province for making surveillance program.Survey sites were chosen by strata sampling according to different geographic locations. Totally 22 survey sites were selected in four regions: East Guangdong, West Guangdong, North Guangdong and the Pearl River Delta. One or two administrative villages in each site were randomly selected for the investigation. Pomacea canaliculata and Achatina fulica collected from fields and other species of freshwater or terrestrial snails obtained in the restaurants and wet markets were examined for the third stage larvae by tissue grinding or lung examination. Rats were captured in the fields, and their hearts and lungs were dissected for adult worms. Rat feces were also collected for the detection of first stage larvae by water precipitation.Large number of P. canaliculata was found in all sites. A. fulica was found in most surveyed sites. Totally 2929 P. canaliculata and 1354 A. fulica were collected with a larva infection rate of 5.9% (172/2929) and 16.5% (223/1354), respectively (P0.01). The average prevalence among the regions was different (P0.01) with the highest prevalence in Pearl River Delta (15.6%, 152/975), especially in Dongguan City of the Delta (34.7%, 78/225). 114 Cipangopaludina sp. and 252 Bellamya sp. were bought from wet markets of 9. sites. Larvae were found only in Bellamya snails from Luoding and Kaiping cities with an infection rate of 1.4% (1/70) and 3.3% (3/91), respectively. Totally 491 rats were captured in 9 sites including Rattus norvegicus, R. flavipectus, Suncus murinus, Mus musculus, Bandicota indica, R. losea and R. rattus, with an average infection rate of 11.4% (56/491). Adult worms were found in R. norvegicus, R. flavipectus and B. indica with a prevalence of 19.8% (52/263), 2.5% (3/118) and 10.0% (1/10), respectively. Thirty-four rodent fecal samples were collected in 7 sites and examined with a larva positive rate of 44.1% (15/34).Foci of Angiostrongylus cantonensis are widely distributed in Guangdong Province as natural infection has been found in its intermediate and definitive hosts.

Although the method of cooperative spectrum sensing can greatly improve the sensing performance, the consumption of system resources will increase as the number of cooperative sensors increases, therefore, the number of cooperative sensors to use is a compromise between sensing performance and consumption of system resources. Firstly, based on the expression for the probability of detection, a sensor set selecting method is proposed; then, a confidence based trustless sensor detecting method is presented to delete the trustless sensors from CRN which would add negative effect on the sensor set selecting method; lastly, based on the two methods above, a confidence based sensor set selecting algorithm is proposed, which not only effectively delete the trustless sensors from CRN but also use fewest cooperative sensors to minimize the consumption of system resources, while still having enough for the sensing performance requirements. Analysis and numerical results illustrate the effectiveness and reliability of the proposed algorithm.

The number of sensors to use for cooperative sensing is a compromise between sensing performance and consumption of system resources. Firstly, the definition of optimal sensor set (OptSS) is given out. Then an optimal selecting method of OptSS is acquired. Lastly, a sub optimal adaptive selecting algorithm of OptSS based on greedy with a lower complexity is proposed, which not only obtains the near-optimal solution rapidly, but also adapts to the variety of dynamic network topologies. Analysis and simulation results demonstrate the effectiveness and reliability of the proposed greedy adaptive sensor set selecting al-gorithm.

To investigate the influence of combined intercostal nerves block-sevoflurane used inhalation anesthesia with laryngeal mask ventilation on the stress response to modified radical mastectomy.60 patients with ASA physical status I-II, aged 33-53 years and scheduled for modified radical mastectomy were randomly divided into group I and group II. 30 cases each group. Patients in both groups received modified radical mastectomy under sevoflurane used inhalation anesthesia with laryngeal mask ventilation, and group II received intercostal nerves block before anesthesia induction. Blood samples were taken before anesthesia,at incision, one hour after incision and 5 minutes after the end of surgery for determination of serum concentration of cortisol and angiotension. Blood pressure and heart rate of patients was also recorded during the operation.Compared with the baseline value before anesthesia, serum cortisol and angiotension increased 5 minutes after the end of surgery in both groups, but the concentration in group I were higher than that in group II. At incision the concentration of cortisol in group I were higher than the baseline value and the same time in group II.Combined intercostal nerves block-sevoflurane used inhalation anesthesia with laryngeal mask ventilation can reduce the stress response in patients undergoing modified radical mastectomy.

To make a survey on the possible imported cases with microfilaremia from a recently identified outbreak focus in Fuchuan County of Guangxi Region.Moving people as temporary laborers from Guangxi and periphery residents were screened by thick blood smears for microfilariae and ELISA for specific IgG4 in Sept 2007.989 persons in cities/districts of Nansha, Panyu, Shantou and Zhongshan were investigated. Among 150 persons from Changtang administrative village of Guangxi, 47 were from two outbreak focuses, Ganshang and Yinshan natural villages in Changtang. Three cases with microfilaremia were found, with a microfilaraemia density of 24, 20 and 2 per 120 microl blood, respectively. The 3 cases were all from the 2 natural villages, with a microfilaraemia positive rate of 6.4% (3/47). Meanwhile, anti-filaria IgG4 was detected for other 1 501 persons, including those from the outbreak focuses, from surr-founding areas and from non-endemic area as control, fifteen cases were found with IgG4 positive. Of the 15 positive cases, 12 were from the 2 outbreak natural villages, with a positive rate of 25.5%, higher than those of others (chi2=295.83, P0.01). The cases with IgG4 positive but microfilaremia negative were reexamined by ICT kit and all showed negative.It is suggested that no further transmission occurs although microfilaremia cases have been imported from the outbreak focus of Guangxi.

An experiment was designed to determine the effect of the fungal endophyte Neotyphodium lolii on the growth, physiological parameters and mineral element content of perennial ryegrass (Lolium perennel L.), when growing at two N supply levels. Endophyte infection had a significant positive effect on both shoot and root growth of ryegrass, but this difference was only significant in the high N supply treatment. At high N supply, endophyte-infected (EI) plants accumulated more soluble sugar in the sheath and the root than endophyte-free (EF) plants. Endophyte infection affected mineral element concentrations in the root more than in the shoot. We found a significant effect of endophyte infection on B, Mn and Mg in the root, but significant effect was only found on B in the shoot. EI plants tended to accumulate less B in the shoot at both N levels, but accumulated more B, Mn and Mg in the root at low N levels. The difference of growth parameters in different periods was significant. The content of soluble sugar and crude protein in the sheath were also dependent on the growth stages of both EI and EF plants.

WiMAX is an emerging technology based on the 802.16 standards to provide high speed and broadband wireless access for mobile stations. Handover is a key operation influencing the quality of communication services. In this paper, the scheme of choosing the suitable base station with the best service for a mobile station in a WiMAX network is studied. A new scheme based on fuzzy logic is proposed to employ the important traffic criteria, including bandwidth, dropping rate, blocking rate, and signal strength. Finally, the simulation is used to investigate the performance of proposed scheme. The simulation results show that the proposed schemes have better performance than conventional schemes, and can achieve the higher bandwidth utilization, the lower blocking rate for new calls, and the lower dropping rate for handover calls.

This paper presents a novel algorithm for localization in wireless sensor networks utilizing a fuzzy inference system at each sensor node. The algorithm using fuzzy distance measuring based on received signal strength information (RSS). The advantage of employing the RSS information is that no extra hardware is needed for localization. The simulation results and indoor experiments demonstrate that the proposed scheme employing fuzzy logic system can localize the mobile sensor nodes with certain accuracy.

To establish a method for efficient induction and expansion of Epstein Barr virus (EBV)-specific cytotoxic T lymphocytes (CTL) in vitro and evaluate the possibility of using this strategy for treatment of nasopharyngeal carcinoma (NPC).EBV-transformed B lymphoblastoid cells (BLCLs) were used as the antigen stimuli and antigen-presenting cells. EBV-specific CTL was induced by co-culture of the autologous peripheral blood mononuclear cells (PBMCs) and the irradiated BLCLs, and expanded with a cocktail method consisting of OKT-3, irradiated homologous PBMC, and IL-2. The specific activity of the CTL against the NPC cells was measured with MTT assay.EBV-specific CTL was successfully induced and expanded by 600 folds. The killing efficiency of the CTL was 76% for autologous BLCLs, 13% for homologous BLCLs, 51% for autologous NPC cells, and 27% for homologous CNE cell line, and after expansion, the corresponding killing efficiencies were 63%, 25%, 49%, and 33%, respectively. The non-specific killing only slightly increased after the expansion.EBV-specific CTL can be successfully induced and expanded in vitro for specific killing of autologous NPC cells, suggesting the potential of this strategy in the treatment of NPC.

For the sake of enhancing stability of least squares constrant modulus equalization algorithm( LSCMA), combining recursive least-squares (RLS) and using robust estimation (RE) from Application Maths, the paper puts forward an new sort of semi-blind constant modulus equalization algorithm that names SB-MRLS-LSCMA.The simulation indicates that the algorithm improves the performance of convergence and stability of the equalizer comparing to traditional LSCMA and several other semi-blind algorithm. And the algorithm can be good for restraining multi-pathway and Rayleigh fading.

Traditional chip LMMSE algorithm has unbearable computational complexity for MIMO HSDPA (high speed downlink packet access) owing to multiple antennas. In order to reduce computational complexity, SMW theorem is used in LMMSE, and furthermore a pilot cancellation module is added. A PC-ILMMSE (pilot cancellation iterative LMMSE) algorithm is proposed. Theoretic analysis and computer simulations show that performance of PC-ILMMSE is superior to traditional LMMSE. But calculation of PC-ILMMSE is much lower than LMMSE

A novel signal recognition and signature code acquisition (SR/CA) method is proposed for DS-SS systems with frequency offset. Based on existing SR/CA methods, the new soft SR/CA method introduces double decision thresholds and an automatic frequency control (AFC) loop. The performance analysis and double thresholds set criteria are discussed. Numerical results show that the soft SR/CA method provides better detection performance, while false alarm probability hardly increases.

The purpose of this paper is to propose a modified explicit rate indication for congestion avoidance (MERICA) scheme for ATM networks. This modified scheme belongs to the class of closed-loop rate-based congestion control scheme. Three aspects are modified for making the scheme to adapt to various traffic types of ATM networks. First, the VBR and CBR traffics are considered. Second, a new congestion eliminating scheme is shown. Third, a new BECN mechanism for available bit rate (ABR) sources is presented. In the simulation model, two environments, LAN and WAN, are simulated to illustrate the performance factors, including the link utilization, the average waiting time, the fairness, and the loss rate. The simulation results show that the link utilization of MERICA performs well; meanwhile, its average delay and fairness are also better than other explicit rate congestion control mechanisms. Furthermore, the most attractive advantage is that MERICA has no loss in LAN and WAN environments.

This paper presents a new load balancing policy in heterogeneous distributed systems. All nodes in this system connected in point-to-point may have different service rates, and each node can serve not only external arrival tasks but also the tasks migrated from the other nodes. The scheduler takes into account the threshold value, based on the ratio of service rates, and the current queue length in determining whether one task shall be migrated to the other node or left for the local node. A Markov process model is used to describe the behavior of the heterogeneous distributed system under the proposed policies. The model is then solved by using the matrix-geometric solution technique. Performance of the policy is compared to that of the generic load balancing policy, no load balancing policy, and the ideal load balancing policy. The results show that the proposed policy is better and closer to the ideal load balancing policy. >

The congestion control scheme which prevents the network from congestion for ATM (asynchronous transfer mode) networks is presented. The proposed congestion scheme consists of two parts: a Markov chain model and a bandwidth allocation method. The Markov chain model is presented to estimate the quality of service of ATM networks, while the bandwidth allocation mechanism is to decide whether the anticipated connection can be accepted. From the simulation and analysis, the result shows that this congestion control scheme can not only multiplex the sources with heterogeneous traffic but also maintain a satisfactory level of the quality of service.

We propose a new gray relational measurement whose gray relational coefficient is called the gray relational coefficient of order k. Gray relational coefficient of order 1 is the traditional gray relational coefficient. With this new gray relational measurement, we can compute the gray relational matrix of order k for variables of systems. If k is large enough, the matrix would show the clusters of variables and the result is objective.

In order to obtain solid phase time-resolved fluorescence immunoassay chelate of new type, 4,4'-di (p-aminophenylethynyl)-6,6'-bis(N,N-bis(ethoxycarbonylmethyl) amino methyl)-2,2'-bipyridine and 4, 4'-di (p-aminophenylethynyl) -6,6'-bis(N, N-bis (t-butoxycarbonyl- methyl) amino methyl) -2,2'-bipyridine were synthesized from 4, 4'-dinitro-2, 2'-bipyridine-6, 6'-dimethyl bis (trifluoroacetate) by four steps hydrolyzation, bromination, esterification and substitution. The structures of the compounds were charactered by differential scanning calorimetry,, infrared spectroscopy, H-1 NMR and high resolution mass spectrometry. The properties and functions of the compounds were studied and compared.

In the present report we further explored the role of paf-acether (paf), a phospholipid cytokine, in the modulation of T cell activation induced via the CD2 and the CD3 pathways. Evidence was obtained that paf inhibited T cell proliferation induced by immobilized CD3 mAb (OKT3i), but potentiated that induced by a combination with the CD2 mAb, anti-(T11.1 + D66). Both effects were dose-dependent between 2 and 10 microM paf, and specific in that lysoPC, a phospholipid closely related to paf, had no effect. The inhibition became apparent after 48 h and was maintained up to 144 h of culture, whereas the enhancement was observed only by 96 h of culture. Interestingly, paf was able to inhibit OKT3i mAb response when added to cultures as late as 24-48 h after the initiation of a 96 h incubation. By contrast, paf enhanced the proliferative response only when added concomitantly with anti-(T11.1 + D66) mAb, suggesting that it modulates an early event of T cell activation. paf, which enhanced T cell proliferation induced via the CD2 pathway, also led to a substantial up-regulation of IL-2 secretion and CD25 expression. Moreover, paf markedly augmented IL-4 secretion upon CD2 mAb stimulation. Finally, when T cells were triggered via the CD3 molecule, paf inhibited the proliferative response but also down-modulated CD25 expression without impairing IL-2 secretion. When considered together, these data demonstrate that paf, a phospholipid cytokine released during inflammatory reactions, play a differential regulatory role in T cell activation induced via the CD3 and CD2 (T11.1 + D66) pathways.