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Signal molecules are stimulators of multiple quroum-sensing virulence and biofilm formation. Small molecule analogues have been suspected as a potent inhibitor in therapeutic strategy. Herein, we synthesized a series of small molecule compounds from the 2, 8-bit derivatives of quinoline by Suzuki coupling reaction. We found that these compounds have the biofilm inhibitory effect in normal condition instead of phosphate limitation state. Furthermore, lacZ reporter strain assay and rhamnolipids as well as pyocyanin experiments showed that these compounds did not affect las and pqs system but reduced the expression of rhl. All these results suggest that quinoline derivatives can be treated as potent inhibitors against biofilm and reduce virulence through the rhl system. This research will be useful in designing new quorum sensing inhibitors to attenuate the infection of bacteria.

In mobile wireless communications, the received signal power is modeled as a combination of path loss, shadow fading and small-scale fading. In previous studies, the lognormality of the shadow fading is generally explained as a multiplicative model. In [1] the author proposed an additive model as a physical basis for shadowing within an "extended local area", where the shadowing can be written as the logarithm of the power of the plane waves. In this paper, based on the additive model, we focus on the correlation of the shadow fading in two extended local areas, the analytical expressions are presented for the correlation coefficient (ρ) of the shadow fading.

This paper discusses the reference signals used in synchronization for LTE system. In general, primary synchronization signal (PSS) correlation based acquisition and reference signals based tracking loop are applied for time and frequency synchronization but it is unclear which legacy reference signals (RS) will be used as the listening RS for radio-interface based synchronization. Besides the legacy cell-specific reference signals (CRS) utilized as the listening RS, the other potential candidate could be either CSI reference signals (CSI-RS) or position reference signals (PRS). Upon performance evaluation, we compare the pros and cons of CRS, CSI-RS and PRS based synchronization and present our views.

The standard OFDM signal requires a cyclic prefix (CP) of length larger than the channel impulse response. This paper investigates the effect of CP length to the capacity of OFDM system. We have found that full CP or none CP may not be optimal in the sense of capacity. Specifically, the capacity is a monotonic function of CP length in the low and high SNR regime and is approximately concave down when SNR is about 3dB.

DFT-S OFDM, short for DFT Spread OFDM, is employed in LTE uplink to reduce the Peak-To-Average Power Ratio (PAPR) introduced by multicarrier transmission. In this paper, we compare the maximum achievable data rate, i.e. the Shannon capacity, of DFT-S-OFDM and OFDM under Rayleigh and with clipping. Our results indicate that, in terms of Shannon Capcity, OFDM outperforms DFT-S-OFDM with ZF or MMSE.

Our aim was to evaluate the safety and effectiveness of extracorporeal cardiac shock wave therapy (CSWT) for the patients with coronary heart disease (CHD) using a randomized, double-blind, controlled clinical trial design. Twenty-five patients with CHD were enrolled in this study. Fourteen of the patients were randomized into the CSWT group and 11 into the control group. We applied the CSWT procedure to each patient by using nine shock treatments during 3 months, but the shock wave (SW) energy was only applied to the patients in the CSWT group and not to the patients in the control group. Technetium-99m sestamibi myocardial perfusion, fluorine-18 fluorodeoxyglucose myocardial metabolism single-photon emission computed tomography (SPECT), and two-dimensional echocardiography were performed to identify segments of myocardial ischemia, myocardial viability, and ejection fraction before and after CSWT. We also followed the patients to evaluate adverse effects. After CSWT, the New York Heart Association class, the Canadian Cardiovascular Society angina scale, nitroglycerin dosage, myocardial perfusion and myocardial metabolic imaging scores of dual-isotope SPECT in the CSWT group were reduced significantly (P = 0.019, 0.027, 0.039, 0.000, 0.001, respectively), and the Seattle Angina Questionnaire scale, 6-min walking test, and left ventricular ejection fraction were increased significantly (P = 0.021, 0.024, 0.016, respectively) compared with those before the SW treatment. All of the parameters in the control group did not change significantly after the treatment (all P > 0.05). No serious adverse effects of CSWT were observed. Cardiac shock wave therapy is a safe and effective treatment for CHD patients.

Performance evaluation of maximum-likelihood (ML) decoded binary linear codes is usually carried out using bounding techniques. In this paper, a new upper bound is presented to improve existing union bounds. The proposed upper bounding is based on probabilities of correct events, while the traditional union bound (UB) is on pair-wise error probabilities. Moreover, the improved upper bounding uses the intersection instead of the union of basic events. The theoretical and simulation results show that the proposed bound is tight than UB.

In this article, an exact closed-form expression is derived for outage probability of decode-and-forward (DF) cooperative communications over independent identically distributed Nakagami-m fading channels. Simulation results verify that the theoretical expressions for the outage probability are correct. The optimal power allocation based on the derived outage probability is also studied.

This article proposes a new algorithm to improve the rate control efficiency of enhanced reverse link medium access control (RLMAC) in the code division multiple access (CDMA) Ix EV-DO release A (Rev. A) system. The new algorithm brings reverse access terminal (AT) pilot power to the RLMAC rate control procedure and makes it easier for a low pilot power user to increase its data rate when the system is slightly loaded and harder to decrease its date rate when the system is heavily loaded. Numerical results of system level simulations show that the new algorithm can bring higher system throughput, lower AT transmission power, and lower system load.

Downlinks of the cellular systems generally have more transmit antennas than receive antennas. To efficiently exploit all antenna resources, a technique that combines the advantage of beamforming and spatial multiplexing has been proposed, which partitions the transmit antennas into neighboring sub-groups. In this article, this technique is further improved by Eq. (1) allowing non-contiguous antenna grouping, and Eq. (2) adopting two new grouping criteria: minimum signal distance maximization (MSDM) criterion and maximum correlation coefficient minimization (MCCM) criterion. Simulation results indicate that these improvements can bring noticeable gains in the Rayleigh flat fading channel environment.

To evaluate the feasibility, safety and efficiency of extracorporeal cardiac shock wave therapy (CSWT) in patients with ischemic heart failure.Fifty patients with ischemic heart failure and left ventricular ejection fraction (LVEF)50% were randomized to CSWT (shots/spot at 0.09 mJ/mm(2) for 9 spots, 9 times within 3 month) or control group. Dual isotope simultaneous acquisition single-photon emission computed tomography with (99)Tc(m)-sestamibi/(18)F-fluorodeoxyglucose ((99)Tc(m)-MIBI/(18)F-FDG) was performed before randomization and at 1 month after CSWT/control to locate and evaluate viable myocardium region. Canadian cardiovascular society (CCS) class sores, NYHA, Seattle Angina Questionnaire (SAQ), 6-min walk test (6 MWT), left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD) and the dosage of nitroglycerin use were compared between two groups at each time point.All patients completed the study protocol without procedural complications. At 1 month, patients in CSWT group experienced improvement in NYHA (P0.01), CCS (P0.01), SAQ (P = 0.021), 6 MWT (P = 0.012) and dosage of nitroglycerin use (P0.01) compared to baseline. LVEF [45.0 (39.0, 48.0) vs. 47.0 (42.0, 50.0) P = 0.001], LVEDD [58.0 (56.0, 59.0) vs. 56.0 (55.0, 58.0) P = 0.002], summed perfused score [23.0 (20.5, 24.5) vs. 20.0 (18.0, 22.0) P0.01] and metabolic score [25.0 (23.0, 26.0) vs. 24.0 (21.5, 25.0) P = 0.028] were also improved in CSWT group. All these parameters remained unchanged in control group between baseline and at 1 month. CSWT was independent factor for improved cardiac function, quality of life and echocardiography parameters after adjusting for known factors which might affect outcome.CSWT could improve symptom, cardiac function, quality of life and exercise tolerance in patients with ischemic heart failure, CSWT might serve as a new, non-invasive, safe and efficient therapy for these patients.

Through clinical observation on an formula containing mainly Ca(OH)(2) for dental canal sterilization to confirm it as an ideal canal sterilizer.5% (M/V) of Ca(OH)(2) in glycerol was used as dental canal sterilizer. Patients with acute or chronic apical periodontitis were randomly selected, and their symptoms were recorded before treatment. The dental canals were prepared routinely only with exception of that the sterilizer was 5%(M/V) of Ca(OH)(2) in glycerol and paper point or cotton point soaked with and the canals were sealed for 5 to 7 days. Then the canals were filled if there was no positive symptom or re-sterilized, if symptom did not totally disappear.Through sterilization with the formula used in this study, the symptom disappeared swiftly. Specifically, after the canals sterilized for one to two times, there was no symptom that could be seen in all patients studied. The rate of symptom disappeared from 89% to 98% could be detected in acute apical periodontitis and the rate of no symptom was from 94% to 99% in chronic periodontitis. Additionally, through the study for more than one year, the formula maintained thin paste state that was convenient for use.In addition to safety, using the formula with Ca(OH)(2) as main sterilizer is effective in dental canal sterilization for the formula dramatically improving the symptom.