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Adopting small-world neural networks of the Hodgkin-Huxley (HH) model, the stimulation parameters in desynchronisation and its possible implications for vagus nerve stimulation (VNS) are numerically investigated. With the synchronisation status of networks to represent epilepsy, then, adding pulse to stimulations to 10% of neurons to simulate the VNS, we obtain the desynchronisation status of networks (representing antiepileptic effects). The simulations show that synchronisation evolves into desynchronisation in the HH neural networks when a part (10%) of neurons are stimulated with a pulse current signal. The network desynchronisation appears to be sensitive to the stimulation parameters. For the case of the same stimulation intensity, weakly coupled networks reach desynchronisation more easily than strongly coupled networks. The network desynchronisation reduced by short-stimulation interval is more distinct than that of induced by long stimulation interval. We find that there exist the optimal stimulation interval and optimal stimulation intensity when the other stimulation parameters remain certain.

We developed a facile method to synthesize core-shell WC@meso-Pt nanocatalysts by carburizing ammonium tungstate and copper nitrate via gas-solid reactions, followed by a Pt replacement reaction. The mesoporous nanocomposite displays higher activity and stability towards methanol electrooxidation than commercial Pt/C catalysts.

The effect of squeezed vacuum input on the optical bistable behavior of a system of N three-level atoms which are simultaneously coupled to a coherent pump field and a squeezed vacuum input is investigated. It is shown that the squeezed vacuum will significantly increase the range of the optical bistability, and the bistability can be controlled by the squeezing photon number and the strength of two-photon correlation.

We discuss the optical bistable behavior of a system of N Λ -type three-level atoms pumped by a coherent input field and coupled to a squeezed vacuum field by treating the optical bistability of such a system as an input-out problem. It is shown that bistability can be realized due to the squeezed vacuum input.

The nondegenerate two-photon interaction of a two-level atom with a broadband multimode squeezed vacuum is investigated. We find that in the two-photon process the squeezed vacuum has a driving effect on the atom which can lead to an ac Stark effect when the average photon number of the squeezed vacuum is larger than a critical value.

A three-level ladder atom driven by two coherent laser fields with rather different frequencies in various kinds of reservoirs is considered. Making use of the master equation and Bloch equation, we calculate numerically and show graphically the steady-state populations versus two-photon detuning. We also discuss and compare the two-photon and one-photon processes occurring for various cases. For a squeezed vacuum, only when the carrier frequency of the squeezed vacuum equals the average of frequencies of the two driving fields and the phase matching condition is fulfilled, will there be a strong two-photon resonant absorption from the squeezed vacuum, a characteristic different from absorption of photons from a classical field; Otherwise, the two-photon ab-sorption rate from the squeezed vacuum will be greatly diminished.

Percutaneous device occlusion and minimally invasive surgical repair for perimembranous ventricular septal defect (pmVSD) are two typical methods to reduce the invasiveness of the conventional operation through a median sternotomy. However, few studies have compared them in terms of effectiveness and cost.Inpatients with isolated pmVSD who had undergone percutaneous device occlusion or minimally invasive surgical repair from June 2009 to June 2012 were reviewed for a comparative investigation between the two procedures.Procedure success was achieved in 80 percutaneous (93.0%) and in 113 surgical (98.3%) procedures (p=0.076). Percutaneous patients were older, with a smaller VSD size than surgical patients (16±11.7 vs 3.8±2.4 mm, p0.001; 4.0±1.2 vs 4.3±1.3 mm, p=0.034, respectively). Major complications occurred in 1 percutaneous (1.2%) and in 4 surgical (3.5%) procedures (p=0.602), and minor complications occurred in 27 percutaneous (33.3%) and in 37 surgical (32.2%) procedures (p=0.991). The surgical repair cost 31% less than the device occlusion (¥20,565±¥3,497 vs ¥29,795±¥2,643, p0.001), where most of the cost was attributed to the occluder in the amount of ¥19,500.Compared with device occlusion, minimally invasive surgical repair can provide comparable efficacy and complication rates. In addition, it is 31% cheaper than device occlusion. In low-income countries where health care resources are limited, medical resources must be judiciously allocated to the treatment that allows for effective treatment of the largest number of patients.

We introduce a scheme based on adiabatic passage that allows for long-range quantum communication through tight-binding chain with always-on interaction. By adiabatically varying the external gate voltage applied on the system, the electron can be transported from the sender's dot to the aim one.We numerically solve the Schr\"odinger equation for a system with a given number of quantum dots. It is shown that this scheme is a simple and efficient protocol to coherently manipulate the population transfer under suitable gate pulses. The dependence of the energy gap and the transfer time on system parameters is analyzed and shown numerically. Our method provides a guidance for future realization of adiabatic quantum state transfer in experiments., Comment: 7 pages, 5 figures. arXiv admin note: text overlap with arXiv:1206.6716

The optimal stenting strategy for the treatment of coronary bifurcation lesions (CBLs) remains uncertain. The present study observed technical feasibility and reliability, 9-month clinical and angiographic outcomes of the modified culotte stenting (MCS) in the treatment of CBLs with drug-eluting stents.A total of 34 consecutive patients with CBLs that required stenting the parent vessel (PV), the main branch (MB) and the side branch (SB) were included. All patients were first assigned to receive MCS for CBL interventions (per MCS), and might be switched to receive the double-kissing-crush stenting (DKS) in case of temporally acute branch occlusion (per protocol).The immediate angiographic or procedural success was achieved in 33/34 (97%) lesions (patients) per MCS, 34/34 (100%) lesions (patients) per protocol with 100% successful final balloon kissing. The long-term clinical success at 9 months was 94% per MCS and 94% per protocol, only 2 patients had reoccurrence of angina but none of them needed target lesion revascularization. There were no procedure-related biomarker elevation, no in-stent thrombosis peri-procedurally and at 9-month follow-up. Quantitative coronary angiography data at 9 months showed that in-stent (6%) or in-segment (6%) binary stenosis was infrequent, and minimal lumen diameter was significantly reduced but late lumen loss was acceptable with only (0.10 ± 0.14) mm for PV, (0.21 ± 0.23) mm for MB and (0.27 ± 0.32) mm for SB.MCS for treatment of CBLs that required dual-stent implantation was technically easier and safer, readily to complete final balloon kissing, and was associated with high immediate success and optimal 9-month outcomes.

The ground state entanglement of the two-mode Bose-Einstein condensate is investigated through a quantum phase transition approach. The entanglement measure is taken as the order parameter and this is a non-local order parameter, which is different from the conventional order parameter of the Mott insulator-superfluid phase transitions. For this non-local order parameter, scaling behavior corresponding to a continuous phase transition is obtained and a power-law divergence near the critical region follows it. This scaling behavior of quantum entanglement is analyzed by the finite-size scaling and the critical exponents are obtained as $\nu = 1.01$ and $\gamma = 0.86$. A close connection between quantum fluctuations and the phase transition of entanglement is also obtained., Comment: 4 figures, accepted by Phys. Rev. A, 2012

This paper uses the conjugate gradient method to optimize the calculation and achieve rapid calculation on the network weights and thresholds, simulates the traditional gradient descent and conjugate gradient algorithm of BP neural network, and discusses the training speed, fault-tolerant generalization ability of the method. The goal is to variously verify the superiority of conjugate gradient algorithm. The simulation results highlight the substantial increase in training speed. In particular, for the generalization ability of damaged network after training, using linear regression method to simulate can also obtain satisfaction result, which supports the conjugate gradient BP algorithm from the new angle.

to investigate the combined effect of rosuvastatin (RSV) and ischemic postconditioning (PC) on myocardial ischemia-reperfusion (I/R) injury in a type 2 diabetic rat model.type 2 diabetic (induced by streptozotocin plus nicotinamide) rats, undergoing 30 min ischemia and 120 min reperfusion, were divided into six groups (n = 10 each): Sham, I/R without other interventions, RSV before reperfusion, PC with 3 cycles of 10 s reperfusion and 10 s ischemia, RSV + PC and RSV + PC + PI3-K inhibitor LY294002. Myocardial infarct size (IS), ultrastructural change and myocardial expression of phosphorylated eNOS/total eNOS were determined.IS and ultrastructural damages were all significantly reduced and myocardial eNOS phosphorylation was significantly increased in RSV and PC groups compared with the I/R group (all P0.05) these beneficial effects were further enhanced by RSV + PC (all P0.05 vs. RSV and PC, respectively). The beneficial effects were significantly attenuated by PI3K inhibitor LY294002.the results indicate that RSV + PC could alleviate myocardial ischemia-reperfusion injury in this type 2 diabetic model by activating PI3K/AKT/eNOS signaling pathway.

Transcatheter Amplatzer occlusion of patent ductus artertiosus (PDA) has emerged as a minimally invasive alternative to surgical closure. The goal of this study was to compare long-term clinical outcomes between two procedures, especially on chronic residual shunt, late or very late procedure-related complications, and regression of pulmonary hypertension and left ventricular dilation.A total 255 patients having isolated PDA with a minimal diameter ofor= 4 mm treated from January 2000 to July 2003 were included in this study and have been followed up until July 2008. The patients were assigned to either the device or surgical closure group according to the patients' and/or their parents' preference. Baseline physical exams, chest roentgenography, electrocardiography, and echocardiography were performed preprocedure and at each follow-up.Seventy-two patients accepted the transcatheter procedure (Group-TC) and 183 underwent surgical operation (Group-SO) for PDA closure, both groups were similar in their demographics and preoperative clinical characteristics. There were no cardiac deaths and late complications such as infectious endocarditis and Amplatzer duct occluder (ADO) dislodge in either group. More acute procedure-related complications were recorded in Group-SO (13.7%) compared with Group-TC (1.4%) (P = 0.004). The recovery time was (8.7 +/- 2.3) days for the Group-SO and (1.3 +/- 0.5) days for the Group-TC (P0.001). The survival freedom from persistent residual shunt, defined as residual shunt that can not resolve automatically, was 91.3% for Group-SO and 98.6% for Group-TC (P = 0.037 by Log-rank test). There was no significant difference in regression of pulmonary hypertension and left ventricular dilation; neither survival freedom from pulmonary hypertension nor abnormal left ventricular end-diastolic volume index were significantly different between the surgical group and the Amplatzer group.Our study confirmed the long-term safety and efficacy of transcatheter Amplatzer occlusion. In comparison to the time-proven surgical closure, transcatheter Amplatzer occlusion was less invasive and associated with fewer complications and residual shunt, and as effective in the regression of pulmonary hypertension and left ventricular dilation.

The hydrolysis/precipitation behaviors of Al3+, Al-13 and Al-30 under conditions typical for flocculation in water treatment were investigated by studying the particulates' size development, charge characteristics, chemical species and speciation transformation of coagulant hydrolysis precipitates. The optimal pH conditions for hydrolysis precipitates formation for AlCl3, PAC(A113) and PAC(A130) were 6.5-7.5, 8.5-9.5, and 7.5-9.5, respectively. The precipitates' formation rate increased with the increase in dosage, and the relative rates were AlCl3 >> PAC(A130) > PACA113. The precipitates' size increased when the dosage increased from 50 mu M to 200 mu M, but it decreased when the dosage increased to 800 AM. The Zeta potential of coagulant hydrolysis precipitates decreased with the increase in pH for the three coagulants. The isoelectric points of the freshly formed precipitates for AlCl3, PAC(A113) and PAC(A130) were 7.3, 9.6 and 9.2, respectively. The Zeta potentials of AlCl3 hydrolysis precipitates were lower than those of PAC(A113) and PAC(A130) when pH > 5.0. The Zeta potential of PAC(A130) hydrolysis precipitates was higher than that of PACA113 at the acidic side, but lower at the alkaline side. The dosage had no obvious effect on the Zeta potential of hydrolysis precipitates under fixed pH conditions. The increase in Zeta potential with the increase in dosage under uncontrolled pH conditions was due to the pH depression caused by coagulant addition. Al-Ferron research indicated that the hydrolysis precipitates of AlCl3 were composed of amorphous AI(OH)3 precipitates, but those of PACA113 and PACA130 were composed of aggregates of Al-13 and Al-30, respectively. Al3+ was the most un-stable species in coagulants, and its hydrolysis was remarkably influenced by solution pH. Al-13 and Al-30 species were very stable, and solution pH and aging had little effect on the chemical species of their hydrolysis products. The research method involving coagulant hydrolysis precipitates based on Al-Ferron reaction kinetics was studied in detail. The Al species classification based on complex reaction kinetic of hydrolysis precipitates and Ferron reagent was different from that measured in a conventional coagulant assay using the Al--Ferron method. The chemical composition of Al-a, Al-b and Al-c depended on coagulant and solution pH. The Al-b measured in the current case was different from Keggin Al-13, and the high Alb content in the AlCl3 hydrolysis precipitates could not used as testimony that most of the Al3+ Was converted to highly charged Al-13 species during AlCl3 coagulation. (C) 2009 Elsevier Ltd. All rights reserved.

To evaluate the clinical effect of transrectal high-intensity focused ultrasound (HIFU) in the treatment of prostate cancer (PCa).A total of 57 PCa patients, 27 localized and 30 advanced, underwent transrectal HIFU with the Sonab- late 500, the localized group treated by transrectal HIFU only, while the advanced group by transrectal HIFU combined with androgen ablation.For the HIFU treatment, the mean operating time, hospital stay and follow-up were 111 mm (ranging from 86 to 153 mm), 3.2 days (ranging from 2 to 18 days) and 18 months (ranging from 6 to 30 months), respectively. The biochemical disease-free rates at 1, 2 and 3 years in the localized group were 86%, 81% and 79%, respectively. While in the advanced group, the serum prostate specific antigen (PSA) was4.0 microg/L in 26 cases (0.51 microg/L in 20) and the prostate volume decreased more than 50% in 21 cases after treated for an average of 8 months (ranging from 3 to 24 months). After transrectal HIFU prostate ablation, the prostate volume reduced, serum PSA lowered, Qmax raised and IPSS improved significantly (P0.05). No serious complications occurred including severe urethrorectal fistula and incontinence.Transrectal HIFU is a safe, effective and minimally invasive therapy for patients with prostate cancer.

The conventional jar test and the monitoring technique of floc size in line were employed to investigate the breakage and regrowth of the flocs formed by PACl. It was found that the breakage and regrowth of flocs varied with coagulation zones. The flocs formed in stabilization zone were of high strength and difficult to break, and could regrow better after broken, with the recovery factor of up to 259%. The flocs formed in charge neutralization zone were of the lowest strength and prone to break, but could reform completely after broken. The flocs formed in restabilization and sweep coagulation zones were also of high strength and difficult to break, but significantly irreversible after broken. The recovery factor of the broken flocs in sweep coagulation zone was only 18.6%. The effects of remixing on the breakage and regrowth of flocs increased with remixing intensity. In sweep coagulation zone, the settling height and mean settling velocity of the interface between flocs blanket and water were lower for the broken and partly reforming flocs than for those unbroken; Moreover, in flocculation settling and zone settling zones, the instantaneous settling velocity of the interface at the same flocs concentration was also lower for the broken flocs than for those unbroken, but in compression settling zone, the instantaneous settling velocity was the same whether the flocs were broken or not.

By increasing particle concentration and C value (root-mean-square velocity gradient) to enhance flocculation, a novel vertical-flow settler was designed to increase sedimentation effectiveness, and to simultaneously improve operational stabilization. Due to the gradual decrease in upward flow-rate of raw water, a floes blanket would form and suspend in the middle section of the settler, not at the bottom as in a conventional clarifier. Enough large floes, resulted from flocculation or filtration, would continuously settle out of the floes blanket, and simultaneously, the floes in raw water or those forming above the blanket would ceaselessly enter the flocs blanket. As a result, the floes concentration in the blanket could keep a dynamic balance. The hydrodynamic shear in the blanket was improved by flow separation, which was induced by the abrupt change in flow channel. Due to the floes blanket and improved hydrodynamic shear, flocculation would be enhanced, which was helpful for removing fine particles in raw water. A comparative study showed that the novel vertical-flow settler had a much better performance in the removal of the particles in raw water than a conventional one, when they treated kaolin suspensions of different concentrations (500, 100 and 50 mg/L, respectively) coagulated by polyaluminum chloride(PACI) at the up-flow rates of I and 2 mm/s, respectively.

A study on electrochemical hydrodehalogenation of pentachloraphenol in aqueous solutions was conducted on porous titanium loaded Pd cathode and the operational parameters were investigated. Chloride ions and phenol is the main products analyzed by GC-MS. Up to 100% electrochemical hydrodehalogenation can be achieved with more than 90% conversion to phenol. The result showed that current in the circle play the most important role of dehalogenation while the best parameter is 300mA in this study. Compared to current, the effect of pH value and flow rate on the current efficiency and energy consumption of dehalogenation is limited. Complete dehalogenation, high current efficiency, low energy consumption and operational convenience confirm the feasibility of this method.

To investigate the safety, feasibility and effectiveness of transrectal high-intensity focused ultrasound (HIFU) in the ablation of canine prostate, 20 dogs were divided randomly into 5 groups. Sixteen canine prostates were treated with the third-generation transrectal HIFU device (Sonablate-500). Transrectal ultrasound images of the prostate and prostatic urethra were observed preoperatively and postoperatively. Serial study was performed 30 min, 30 days, 60 days and 180 days after the therapy. The rectum, periprostatic tissues, and prostate were excised en bloc and the tissues were fixed for gross and histological analysis. Our results showed that the average maximal diameter of prostatic urethra was 0.59+/-0.11 cm before the operation and 2.57+/-0.98 cm 60 days after the operation. The volume of prostate was 6.5+/-3.12 cm(3) before the treatment while the volume was 4.13+/-0.23 cm(3) 60 days after the treatment and the differences were statistically significant (P0.05). Histologically, there was a clear demarcation between the necrotic area of the treated tissues and the unaffected surrounding tissues. All the necrotic tissues in the targeted zone broke off and the prostatic urethra became cavitary 60 days later. The more frequent complications were urinary retention and frequency and hematuria. No rectal injury occurred during the treatment. It is concluded that the third-generation transrectal HIFU is capable of destroying prostatic tissue, substantially increasing the width of the prostatic urethra without causing injury to the adjacent tissues. The risk of postoperative complications associated with HIFU was low. HIFU may become a safe, effective and minimally invasive alternative for the treatment of prostatic diseases.

Polyaluminum coagulant with a content of 76.8% of Al30 (PACAl30) was prepared. Its coagulation behaviors were compared with high Al13 content polyaluminum coagulant (PACAl13) and AlCl3. The species stability was studied using Al-Ferron method and 27Al NMR. The coagulation performances were investigated by studying the rate of flocs development, the turbidity removal efficiency and charge neutralization capacity under fixed pH conditions and uncontrolled pH conditions. The effect of pH on coagulation was also studied. The results show that PACAl30 are stable for using as coagulant. PACAl30 causes less pH depression than PACAl13. The charge neutralization capacity of PACAl30 is slightly lower than that of PACAl13 at pH6.8 and higher at pH 6.5. PACAl30 achieves the most effective turbidity removal in these three coagulants. And it acts effectively within a much broader dosage range and a wider pH range when compared with PACAl13. PACAl30 achieves the highest turbidity removal due to its strong flocs formation capacity. The results verify that Al30 is another highly active coagulation/flocculation species for turbidity removal.

The effect of acidification and heat treatment of raw red mud (RM) and fly ash (FA) on the sorption of phosphate was studied in parallel experiments. The result shows that a higher efficiency of phosphate removal was acquired by the activated samples than by the raw ones. The sample prepared by using the RM stirred with 0.25 M HCl for 2h (RM0.25), as well as another sample prepared by heating the RM at 700 degrees C for 2h (RM700), registered the maximum removal of phosphate (99% removal of phosphate). This occurred when they were used in the phosphate sorption studies conducted at pH 7.0 and 25 degrees C with the initial PO(4)(3-) concentration of 155 mg P/l. The FA samples treated in the same way described above can achieve 7.0 and 8.2 mg P/l phosphate removal for FA0.25 and FA700 respectively, corresponding to 45.2% and 52.9% removal. The activated materials performed higher phosphate removal over broader pH range compared with the raw ones. The influences of various factors, such as initial pH and initial phosphate concentration on the sorption capacity were also studied in batch equilibration technique. Solution pH significantly influenced the sorption. Each sample achieved the maximal removal of phosphate at pH 7.0. The amount of phosphate removal increased with the solute concentration. The Freundlich and Langmuir models were used to simulate the sorption equilibrium. The results indicate that the Langmuir model has a better correlation with the experimental data than the Freundlich model.

The influence of the stimulation parameters on the de-synchronization of small world Hindmarsh-Rose (H-R) neural network is numerically investigated in the vagus nerve stimulation therapy for epilepsy. The simulation shows that synchronization evolves into de-synchronization when a part of neurons (about 10 percent) is stimulated with a pulse current signal. The network de-synchronization appears to be sensitive to the stimulation parameters. For the case of the same stimulation intensity, those weakly coupled networks reach de-synchronization more easily than strongly coupled networks. There exist an optimal stimulation interval and period of continuous stimulation time when other stimulation parameters remain invariable.