Short Discharge Time Research Articles

Discharge properties of human diaphragm motor units with ageing.

Ageing is associated with changes in the respiratory system including in the lungs, rib cage and muscles. Neural drive to the diaphragm, the principal inspiratory muscle, has been reported to increase during quiet breathing with ageing. We demonstrated that low-threshold motor units of the human diaphragm recruited during quiet breathing have similar discharge frequencies across age groups and shorter discharge times in older age. With ageing, motor unit action potential area increased. We propose that there are minimal functionally significant changes in the discharge properties of diaphragm motor units with ageing despite remodelling of the motor unit in the periphery. There are changes in the skeletal, pulmonary and respiratory neuromuscular systems with healthy ageing. During eupnoea, one study has shown relatively higher crural diaphragm electromyographic activity (EMG) in healthy older adults (>51years) than in younger adults, but these measures may be affected by the normalisation process used. A more direct method to assess neural drive involves the measurement of discharge properties of motor units. Here, to assess age-related changes in neural drive to the diaphragm during eupnoea, EMG was recorded from the costal diaphragm using a monopolar needle electrode in participants from three age groups (n≥7 each): older (65-80years); middle-aged (43-55years) and young (23-26years). In each group, 154, 174 and 110 single motor units were discriminated, respectively. A mixed-effects linear model showed no significant differences between age groups for onset (group mean range 9.5-10.2Hz), peak (14.1-15.0Hz) or offset (7.8-8.5Hz) discharge frequencies during eupnoea. The motor unit recruitment was delayed in the older group (by ∼15% of inspiratory time; p=0.02 cf. middle-aged group) and had an earlier offset time (by ∼15% of inspiratory time; p=0.04 cf. young group). However, the onset of multiunit activity was similar across groups, consistent with no global increase in neural drive to the diaphragm with ageing. The area of diaphragm motor unit potentials was ∼40% larger in the middle-aged and older groups (P<0.02), which indicates axonal sprouting and re-innervation of muscle fibres associated with ageing, even in middle-aged participants.

Finite volume methods for numerical simulation of the discharge motion described by different physical models

This paper deals with the numerical solution of an ionization wave propagation in air, described by a coupled set of convection-diffusion-reaction equations and a Poisson equation. The standard three-species and more complex eleven-species models with simple chemistry are formulated. The PDEs are solved by a finite volume method that is theoretically second order in space and time on an unstructured adaptive grid. The upwind scheme and the diamond scheme are used for the discretization of the convective and diffusive fluxes, respectively. The Poisson equation is also discretized by the diamond scheme. The results of both models are compared in details for a test case. The influence of physically pertinent boundary conditions at electrodes is also presented. Finally, we deal with numerical accuracy study of implicit scheme in two variants for simplified standard model. It allows us in the future to compute simultaneously and efficiently a process consisting of short time discharge propagation and long-term after-discharge phase or repetitively pulsed discharge.

Comparison short time discharge with long time discharge following uncomplicated percutaneous coronary intervention for Non-ST elevation myocardial infarction patients

BackgroundThe rational length of stay following non-complicated percutaneous coronary intervention (PCI) for Non-ST elevation myocardial infarction (NSTEMI) patients remains controversial. Few studies have examined the impact of early discharge on short-term outcomes in NSTEMI patients, but short-time discharge is not uncommon in real world practice. This study examined the impact of short time discharge following non-complicated PCI on 30-day net adverse clinical events in NSTEMI patients.MethodsThis retrospective study enrolled 1424 consecutive patients with NSTEMI diagnoses who underwent non-complicated PCI. Of these patients, 432 were discharged early (< 24 h), whereas the remaining 992 NSTEMI patients underwent routine discharge. The primary end points of the study were the net adverse clinical events including major adverse cardiac or cerebral events or access site vascular/bleeding complications within 30 days. The differences between the two groups were analyzed after propensity score matching to reduce selection bias.ResultsThe incidence of crude 30-day net adverse events was numerically higher in the long-time discharge group at 11.6% (115/992) compared with 8.6% (37/432) in the short-time discharge group, although this difference was not significant (P = 0.09). This difference was mainly due to lesser radial access selected in the long-time discharge group (827/932, 83.4% vs. 387/432, 89.5%, P < 0.0005). After PS matching to balance the access difference, there was no significant difference in the incidence of the events mentioned above between two groups.ConclusionsIf an NSTEMI patient undergoes PCI without any procedural or hospital complications, short-time discharge after successful PCI would be feasible and safe in selected NSTEMI patients.

Nanosecond pulsed plasma assisted dry reforming of CH4: The effect of plasma operating parameters

Dry reforming is a promising approach to converting CH4 and CO2 (i.e., two common greenhouse gases) into clean fuels and valuable chemicals. Non-thermal plasma, acting as an alternative to the traditional reforming processes, achieves considerable gas conversion with low energy consumption under mild operating conditions. In this study, CH4 and CO2 were converted to syngas (i.e., H2 and CO) in a nanosecond pulsed dielectric barrier discharge plasma at a total gas flow rate of 50 sccm. Through evaluating the effects of electrical parameters on reforming performance, the experimental results showed that CH4 and CO2 conversions increased with the increase of pulse repetition frequency owing to the increased energy injection. Shorter rise and fall times resulted in better CH4 and CO2 conversions and higher energy conversion efficiencies, due to the rapid acceleration of electrons in a shorter discharge time. In the case where the optimal pulse peak width was 150 ns, the secondary discharge was improved because of the charge accumulation in the primary discharge, thereby increasing the CH4 and CO2 conversions. Among all experiments, when the pulse repetition frequency was 10 kHz and the discharge power was 55.7 W, the maximum conversions of CH4 and CO2 were 39.6% and 22.9%, respectively, while the total energy conversion efficiencies of the syngas and all detected products were 5.0% and 7.1%, respectively. Furthermore, an optical emission spectroscopy was used to characterize the active species formed during the reforming process.

State-of-charge determination of Li/SOCl2 primary battery by means of electrochemical noise measurement

Electrochemical noise measurements were performed on a commercially available Li/SOCl2 primary battery at different state-of-charge values. Power spectral density frequency dependencies were calculated in order to ascertain their possible use for calibrating the spectral array for state-of-charge identification of sample batteries. The dependence of spectrum slope on state-of-charge value was linearly approximated to obtain the equation for recalculating the spectrum slope value into the corresponding state-of-charge value. Twenty-four sample batteries of the same type were discharged to different state-of-charge values. Following this, a state-of-charge identification test was applied for each battery and electrochemical noise was measured during short-time discharge. A calibration equation was used to calculate the state-of-charge values for each sample battery using the appropriate electrochemical noise spectrum slope value. The state-of-charge value was identified by electrochemical noise test with more than 10% precision for the majority of the batteries. For the first time, the electrochemical noise method was experimentally demonstrated to be of practical application for evaluating the condition of chemical power sources using a fully automated technique. This approach has shown competitive results when compared with electrochemical impedance and DC voltage methods.

New Design of Ion Blower Based on Needle-Dielectric-Needle Bipolar Corona Discharge

We present here a new design of ion blower based on bipolar corona discharge of needle-dielectric-needle configuration. With the help of the dielectric plate, the new ion blower can endure higher voltage before spark than the traditional bipolar corona discharge, with the similar discharge characteristics and current-voltage curve. The high operating voltage provides a much greater ionic wind velocity compared with the traditional needle-to-needle corona. The neutral ionic wind can reach as far as 0.45m with a velocity of 0.2m/s. This feature is very helpful for eliminating mechanical rotating components in the design of ion blowers, so that the size of ion blower can be greatly compressed and the noise significantly reduced, which is more suitable for electrostatic elimination in small areas and some specific scenarios. The design of self-balancing regulation unit can effectively monitor the charged characteristics of mixed ion wind and make corresponding adjustments to ensure the neutrality of positive and negative discharge. This new ion blower has an excellent performance, including an offset voltage of ±5V, a short discharge time of 5s or less at distance of 20cm.

Topical Tranexamic Acid for the Treatment of Acute Epistaxis: A Systematic Review and Meta-analysis.

To compare topical tranexamic acid (TXA) with control groups for the treatment of acute epistaxis assessing bleeding cessation, discharge within 2 hours, rebleeding rates, complication rates, and patient satisfaction. PubMed, CINAHL, LILACS, Scopus, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched from inception to November 2018. All randomized controlled trials comparing topical TXA with control groups for the treatment of acute epistaxis in humans were included. There were no age, language, or date restrictions. Data were double extracted into a predefined worksheet, and quality analysis was performed using the Cochrane Risk of Bias tool. Three studies (n = 408 patients) were identified. Topical TXA was not associated with a statistically significant difference in cessation of bleeding within 30 minutes. However, more patients were discharged within 2 hours of arrival, there were fewer episodes of rebleeding within both the first 24 hours and at 1 week, and there was higher patient satisfaction in the TXA group. There was no difference identified in complication rates. Relevance to Patient Care and Clinical Practice: This review compares topical TXA with control groups for epistaxis and discusses the risks and benefits of adding this therapy to usual care. Topical TXA appears to be a reasonable option for the treatment of acute epistaxis, with reduced rebleeding rates, shorter discharge times, and minimal risk of complications. Topical TXA may be considered as part of the treatment of acute epistaxis.

In-plume acceleration of leading-edge ions from a pulsed plasma thruster

Pulsed plasma thrusters are a form of electric propulsion for spacecraft. Their research has undergone recent growth due to an increasing interest in small satellites. However, their plasma plumes are transient and challenging to study due to the extremely short discharge time that lasts in the order of microseconds. The plasma plume is accelerated by a combination of electrothermal and electromagnetic forces. With electromagnetic acceleration, the ions are typically thought to be only accelerated within the thruster by the Lorentz force. Estimated downstream exhaust velocities have ranged widely from 5 to 60 km s−1, with values on the lower end corresponding to electrothermal acceleration. However, we show here that the fastest leading-edge ions continue to accelerate in the plume even in the absence of electromagnetic forces. Pulsed plasma thruster plumes are composed of electrons and a mixture of ion species with different ionization levels. Due to this quasi-neutrality of the plasma plume with electrons featuring much larger velocities than ions, we suggest that the acceleration might be ambipolar in nature. The leading-edge ions eventually reach velocities in excess of 100 km s−1, far greater than values typically associated with electrothermal acceleration. This indicates that care must be taken in the accurate measurement of the ion velocity in the plume. The ion plume may also be more energetic than previously believed. Furthermore, we also propose that simple extrapolation can be used to determine the actual exit plane ion velocity; this value can be used as accurate input data for future simulations.

Preparation of metal-organic framework-derived nitrogen-doped porous carbon and study of its supercapacitive performance in potassium citrate electrolyte

As a new kind of power storage, supercapacitors have attracted much attention due to their short charge and discharge time, good cycle performance, large power density, and environmental friendliness. However, the main drawback of supercapacitors is lower energy density than batteries, as well as high cost per unit energy. Herein, the metal-organic frameworks compound [Zn3(OH)(BTC)2(C4N2H11)(H2O)]n was used as carbon precursor to prepare the nitrogen-doped porous carbon (ZMFC-T) by one-step carbonization process. We investigated the influences of carbonization temperature on the specific surface area, pore size distribution and electrochemical properties. The results show that the ZMFC-800 has a specific surface area of 1557 m2 g−1, an average pore size of 3.85 nm, and nitrogen content of 5.25%. In the 1 M potassium citrate electrolyte solution, the stable voltage window is 2 V and the energy density is 65.28W h kg−1. In potassium citrate electrolyte, ZMFC-800 has a strong charge storage capacity and high energy density. This work sheds a new light on the potential for developing superior nitrogen-doped porous carbon for energy storage devices.

Using Six Sigma DMAIC Methodology and Discrete Event Simulation to Reduce Patient Discharge Time in King Hussein Cancer Center.

Short discharge time from hospitals increases both bed availability and patients' and families' satisfaction. In this study, the Six Sigma process improvement methodology was applied to reduce patients' discharge time in a cancer treatment hospital. Data on the duration of all activities, from the physician signing the discharge form to the patient leaving the treatment room, were collected through patient shadowing. These data were analyzed using detailed process maps and cause-and-effect diagrams. Fragmented and unstandardized processes and procedures and a lack of communication among the stakeholders were among the leading causes of long discharge times. Categorizing patients by their needs enabled better design of the discharge processes. Discrete event simulation was utilized as a decision support tool to test the effect of the improvements under different scenarios. Simplified and standardized processes, improved communications, and system-wide management are among the proposed improvements, which reduced patient discharge time by 54% from 216 minutes. Cultivating the necessary ownership through stakeholder analysis is an essential ingredient of sustainable improvement efforts.

Effect of Circuit Parameters and Environment on Shock Waves Generated by Underwater Electrical Wire Explosion

The electrical explosion of wire (EEW), which can generate a convenient, stable, and controllable shock wave (SW), is gradually acted as a physical and environmentally friendly enhanced oil recovery technology in petroleum industry. In order to establish the relationship between the SWs and EEW, the process and mechanism of underwater EEW were investigated and discussed as a function of recipe current, voltage, and pressure in the test conditions. This work describes the effect of wire diameter, capacitance, energy deposition, water conductivity, and temperature on the pressure of SWs. It was found that the amplitude of SWs has a close relationship to the energy deposition in vaporization process. Under the same stored energy of different capacitors, the energy deposition in vaporization stage is more efficient with high charging voltage and low capacitance in a stable explosion, because of the high magnetic pressure and short discharge time. While, the water conductivity and temperature have a significant effect on current and voltage in vaporization stage. The shunt effect of saline water and high thermal conductivity of high-temperature water effect the energy deposition in this stage, which made the amplitude of SWs are falling.

Calibration parameter drift compensation of metal resistive bolometers operating in a thermal varying environment

The ITER bolometer diagnostic will have to provide accurate measurements of the plasma radiation in a varying thermal environment of up to 250°C. Current fusion experiments perform regular in situ calibration of the sensor properties, assuming stable calibration parameters within short discharge times, e.g. 10s on ASDEX Upgrade. For long-pulse fusion experiments, e.g. W7-X, the diagnostic is operated with water cooling for achieving a stable temperature environment. However, ITER will be equipped with about seventy bolometer cameras and is planned to have discharge times of up to 1h. Due to space restrictions, active cooling is not available for all locations. Thus, an alternative approach is required to allow for compensation of the changing calibration values due to thermal drifts. This paper demonstrates a method using the Wheatstone bridge current of the sensor to calculate in real-time the changing calibration values, such as the heat capacity and the thermal time constant. It is shown, that the thermal calibration parameter drift can be calculated by either extrapolating from the initial values or using a previously determined look-up table. Measurements in the ITER bolometer vacuum test facility (IBOVAC), used to simulate ITER-relevant thermal and vacuum environment, show that the change of the calibration values can be predicted during repeated thermal cycles over a duration sufficient for ITER discharges and even longer. Confidence intervals for the typical in situ calibration method are determined and compared with the proposed extrapolation and look-up method for ITER, showing that these methods provide an equivalent quality of the measurement results.

MHD-RLC discharge model and the efficiency characteristics of plasma synthetic jet actuator

Major factors affecting efficiency of plasma synthetic jet actuator (PSJA) are analyzed based on a new discharge model in the present paper. The model couples the magnetohydrodynamics (MHD) equations with the resistor–inductor–capacitor (RLC) equations, and is able to resolve the time-dependent voltage fall on the sheath region and arc region, which is critical in analyzing energy loss in the heating process. This model is integrated into the commercial CFD software by a two-equation method. Results show that in a typical capacitive discharge at microsecond scale, the maximum energy loss is the sheath energy loss, which accounts for nearly half of the discharge energy, while the radiation loss is less than 5%. The discharge time is an important parameter for the PSJA efficiency. A short discharge time less than 1μs will effectively reduce the sheath energy loss, while a longer discharge time will decrease the thermodynamic efficiency.

Comparison of two energy storage options for optimum balancing of wind farm power outputs

This study presents a simple methodology for analysing and optimising combined wind generation and storage schemes, using both technical and economic performance criteria. The study provides a detailed analysis of the performance of two storage options for such a scheme: pumped storage hydro (PSH) and battery energy storage systems (BESSs). The analysis is carried out using recorded data from an actual UK wind farm (WF), information on the UK electricity market, and currently available PSH and BESS storage technologies to estimate and compare performance of the considered wind generation–storage schemes over the entire lifetime. The results show that an optimised generation–storage scheme can significantly reduce the variability of power outputs and increase the profitability of the WF. It is further shown that optimised PSH-based schemes have better economic performance than BESS schemes, as the latter are limited by the short discharge times. The approach developed in this study could be used during the initial design and planning stages, in order to select and optimise the type and size of energy storage for a combined wind generation–storage scheme.

Dielectric Spectroscopy of Polyimide Films Treated by Nanosecond High Voltage Pulsed Driven Electrical Discharges in Water

Dielectric properties of aromatic polyimide films treated by nanosecond pulsed electrical discharges generated in distilled water were evaluated with respect to permittivity and its dependency on discharge time. The relative permittivity of the polyimide films decreased after treatment by water plasma. The largest decrease was observed after a short discharge time, from a value of 3.6 for the untreated sample to 1.92 for the 10 min plasma treated samples. XRD analysis has shown a slight increase of the degree of intermolecular ordering and stronger π–π interactions during plasma treatment over shorter periods of time. However, the distance between the chains was also increasing, giving rise to an increased free volume. This effect may be responsible for the decrease of the relative permittivity of the polymer film.

Micro–Macro Analysis of Capacitor Discharge Sintering in Copper–Diamond Bead

Capacitor Discharge Sintering (CDS) is an ultrafast electric current assisted sintering method (ECAS) suited for electrically conductive metallic and metal‐ceramic composite powders. The technique is a solid state near net shape sintering process which is in general characterized by a very short discharge time (tens of milliseconds), very high current intensity peak (up to 350 kA) and relatively high pressure (up to 1 GPa) with minimum shrinkage. Computer modeling comes to aid in the setup of industrial processes to produce enhanced sintered products such as copper–diamond beads for stone cutting applications. The simulation of the CDS process introduces a new class of nonlinear problems, involving a complex bulk and contact multiphysics with an intricate coupling of micro–macro phenomena. The work presents a micro–macro CDS model along with the solution strategy developed to assess the densification behavior of a copper–diamond bead for stone cutting applications. The overall CDS model implements a four‐way coupling strategy which combines the relevant partial differential equations governing the electrical, thermal, and stress–strain fields over the macroscopic scale of the CDS system, with the densification kinetic model governing the particle scale phenomena. The results are presented in terms of field and shrinkage variables as a function of space and time.

VRLA Battery SOH Estimation Based on WCPSO-LVSVM

The correlation between operation parameters including coup de fouet and SOH was analyzed to choose the input parameters of the battery SOH estimation model, and then the battery SOH estimation model was made based on least square support vector machine (LSSVM). For more prediction accuracy and efficiency, the advanced particle swarm optimization (WCPSO) is used to optimize the parameters of the LS-SVM regression model. The battery SOH was estimated only with measured data (plateau voltage, discharge rate and temperature) of short time discharge, so it is efficient. The verification result shows that the WCPSO-LSSVM model can be used to predict the battery SOH, and the precision is above 93%.

Degradation of 2,4-dichorophenol by pulsed high voltage discharge in water

2,4-dichorophenol (2,4-DCP) was degraded in a pulsed high voltage discharge system with particular focus on the optimum of processing parameters and identification of the intermediate products. By increasing peak voltage or frequency, the 2,4-dichorophenol degradation could be sped up. The energy input was mounted up from 0.0057 to 0.0397kWh and 2,4-DCP degradation efficiency was enhanced from 58% to 99% in 42min by increasing peak voltage from 18kV to 26kV. Under the same 2,4-DCP degradation efficiency, less energy input was required for higher pulse frequency with a shorter discharge time. Higher pH value was advantage for 2,4-DCP degradation while salt content was proved to have little effect on 2,4-DCP degradation in the present discharge reactor. From the identifications of main intermediates resulted from 2,4-DCP degradation, it is illustrated that the degradation is induced by OH, which could mainly attack the Ortho-position of the OH group to form 3,5-dichloro-1,2-benzenediol or substitute the Cl group in 2,4-DCP to produce 2-chlorohydroquinone. The 2-chlorohydroquinone could be further reacted with OH to produce 1,2,4-trihydyoxybenzene. Additional, some ring-opened products such as (e,e)-2,4-hexadienal, formic, oxalic, maleic and d-(+)-malic acid were recognized by GC-MS and Ion Chromatograph detection.

Ketamine, propofol and low dose remifentanil versus propofol and remifentanil for ERCP outside the operating room: Is ketamine not only a “rescue drug”?

SummaryBackgroundEndoscopic retrograde cholangiopancreatography ERCP is a painful and long procedure requiring transient deep analgesia and conscious sedation. An ideal anaesthetic that guarantees a rapid and smooth induction, good quality of maintenance, lack of adverse effects and rapid recovery is still lacking.This study aimed to compare safety and efficacy of a continuous infusion of low dose remifentanil plus ketamine combined with propofol in comparison to the standard regimen dose of remifentanil plus propofol continuous infusion during ERCP.Material/Methods322 ASAI-III patients, 18–85 years old and scheduled for planned ERCP were randomized. Exclusion criteria were a predictable difficult airway, drug allergy, and ASA IV–V patients.We evaluated Propofol 1 mg/kg/h plus Remifentanil 0.25 μg/kg/min (GR) vs. Propofol 1 mg/kg/h plus Ketamine 5 μg/kg/min and Remifentanil 0.1 μg/kg/min (GK).Main outcome measures were respiratory depression, nausea/vomiting, quality of intraoperative conditions, and discharge time. P≤0.05 was statistically significant (95% CI).ResultsRespiratory depression was observed in 25 patients in the GR group compared to 9 patients in the GK group (p=0.0035). ERCP was interrupted in 9 cases of GR vs. no cases in GK; patients ventilated without any complication. Mean discharge time was 20±5 min in GK and 35±6 min in GR (p=0.0078) and transfer to the ward delayed because of nausea and vomiting in 30 patients in GR vs. 5 patients in GK (p=0.0024). Quality of intraoperative conditions was rated highly satisfactory in 92% of GK vs. 67% of GR (p=0.028).ConclusionsThe drug combination used in GK confers clinical advantages because it avoids deep sedation, maintains adequate analgesia with conscious sedation, and achieves lower incidence of postprocedural nausea and vomiting with shorter discharge times.

The infusion method trial of void vs standard catheter removal in the outpatient setting: a prospective randomized trial

• To ascertain if filling the bladder with warm normal saline before trial of void (TOV) reduces time to decision of outcome of TOV and time to discharge compared with standard in-dwelling catheter (IDC) removal in the outpatient setting. • A prospective randomized controlled trial (not blinded) was carried out in the day procedure unit. Randomization was done using computer-generated random numbers. The sample size was calculated based on initial pilot data using α= 0.05 and β= 0.2 and a clinically important reduction of ≥60 min for time to decision of outcome of TOV (primary outcome measure). • In all, 60 consecutive patients were recruited from two referral sources: presentations of acute urinary retention to the emergency department and patients discharged home after failing TOV postoperatively. • The infusion method group (32 patients) had 300-500 mL warm normal saline infused into the bladder before removing their IDC and the control group (28) had standard IDC removal. • Data were collected and analysed using the two-tailed Mann-Whitney U-test. Statistical significance was set at P < 0.05. • The median time to decision was 135.0 (95% confidence interval CI 95.0-190.0) min in the infusion group and 247.5 (95% CI 189.6-294.1) min in the control group. • Patients undergoing a bladder infusion had a shorter discharge time [180.0 (95% CI 126.0-226.9) min] than patients in the standard-IDC-removal group [262.5 (95% CI 233.8-315.0) min]. • The infusion arm shortened time to decision by 112.5 min (P < 0.001) and time to discharge by 82.5 min (P < 0.001). • Furthermore, patients in the infusion group were 1.56 times more likely to achieve catheter-free state after TOV (risk ratio 1.56, 95% CI 1.03-2.36; P= 0.03). • The infusion method for TOV is safe and expeditious, making it ideal for the outpatient setting. This randomized study shows that the infusion method enables a rapid determination of outcome of TOV with a greater chance of success and shortened discharge times.