Prediction of right ventricular dysfunction from radiographic estimates of right descending pulmonary artery in hemodynamically stable pulmonary embolism patients

Background: The evaluation of right ventricular (RV) dysfunction by echocardiography isone of the most important established determinants of the prognosis of acute pulmonary embolism.The aim of the study was to investigate possible association between diameter of rightdescending pulmonary artery on chest X-rays and RV dysfunction by echocardiography inhemodynamically stable pulmonary embolism patients.Methods: Eighty-nine patients with the diagnosis of hemodynamically stable pulmonaryembolism were included.Results: The frequency of RV dysfunction was signifi cantly higher in patients with anenlarged right descending pulmonary artery on chest X-rays (p = 0.001). There wasa signifi cant positive correlation between the diameter of the right descending pulmonary arteryon postero-anterior chest X-rays and the diameter of the RV (r = 0.469; p = 0.002). Diameterof right descending pulmonary artery on chest X-rays was also found as a signifi cant predictorof RV dysfunction besides the troponin-T levels and systolic pulmonary arterial pressure (p < 0.05).Conclusions: Diameter of right descending pulmonary artery on chest X-rays may provideinformation about the risk for pulmonary embolism patients and may be used as a prognosticradiological parameter for the appropriate management of acute pulmonary embolism

Side by Side Battery Technologies with Lithium‐Ion Based Batteries

In recent years, the electrochemical power sources community has launched massive research programs, conferences, and workshops on the “post Li battery era.” However, in this report it is shown that the quest for post Li‐ion and Li battery technologies is incorrect in its essence. This is the outcome of a three day discussion on the future technologies that could provide an answer to a question that many ask these days: Which are the technologies that can be regarded as alternative to Li‐ion batteries? The answer to this question is a rather surprising one: Li‐ion battery technology will be here for many years to come, and therefore the use of “post Li‐ion” battery technologies would be misleading. However, there are applications with needs for which Li‐ion batteries will not be able to provide complete technological solutions, as well as lower cost and sustainability. In these specific cases, other battery technologies will play a key role. Here, the term “side‐by‐side technologies” is coined alongside a discussion of its meaning. The progress report does not cover the topic of Li‐metal battery technologies, but covers the technologies of sodium‐ion, multivalent, metal–air, and flow batteries

Feasibility and Limitations of High-Voltage Lithium-Iron-Manganese Spinels

Positive electrodes with high energy densities for Lithium-ion batteries (LIB) almost exclusively rely on toxic and costly transition metals. Iron based high voltage spinels can be feasible alternatives, but the phase stabilities and optimal chemistries for LIB applications are not fully understood yet. In this study, LiFe$_{x}$Mn$_{2-x}$O$_{4}$ spinels with x = 0.2 to 0.9 were synthesized by solid-state reaction at 800 °C. High-resolution diffraction methods reveal gradual increasing partial spinel inversion as a function of x and early secondary phase formation. Mössbauer spectroscopy was used to identify the Fe valences, spin states and coordination. The unexpected increasing lattice parameters with Fe substitution for Mn was explained considering the anion-cation average bond lengths determined by Rietveld analysis and Mn$^{3+}$ overstoichiometries revealed by cyclic voltammetry. Finally, galvanostatic cycling of Li-Fe-Mn-spinels shows that the capacity fading is correlated to increased cell polarization for higher upper charging cut-off voltage, Fe-content and C-rate. The electrolyte may also contribute significantly to the cycling limitations

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Modeling of Silicon-Air Batteries

In order to improve the lifetime and performance of an electric drive train system, one of the most challenging tasks is to improve the performance of the electrochemical energy storage device in terms of the power and energy density. The energy density of current electrochemical concepts, such as Li-ion batteries, is still far from meeting all demands due to technological and thermodynamical limitations. Therefore, new electrochemical energy storage concepts with enhanced energy density, such as metal-air batteries, are currently being investigated. Silicon-air batteries, a recent concept of metal-air batteries, have been researched over the past few years. From a thermodynamic point of view, the silicon-oxygen couple is very promising and attractive. The theoretical energy density of silicon-air batteries ( ) are close to lithium-air batteries ( ) which is the highest capacity among all the batteries. The aim of this work is to model primary silicon-air batteries by computationally to evaluate the performance of the battery and improve the understanding of the system. In that respect, we developed a mathematical model of the battery on the basis of the mechanisms discussed in previous experimental studies. Our mathematical model is based on the electrochemical processes including reactions, transport mechanisms, oxygen dissolution, volume conditions, and nucleation and growth processes. Finally, we investigate remarkable effect of water addition into the electrolyte with our simulations. We discuss our results in terms of nucleation and growth in the battery, half-cell potentials of the electrodes, spatial distribution of crystallization in the electrode pores, discharge of the battery at various water contents, and discharge of the battery at various discharge currents

Investigation and Development of a Resource Efficient Metal–Air Battery – Silicon–Air

Interest on metal–air batteries has been emerging due to increased demand on resource efficient battery technologies and development of materials. By possessing high theoretical specific energies as well as using low cost, safe and abundant electrode materials, metal–air batteries are promising energy storage devices which could fulfill the current demands. A recent concept of metal–air batteries, Si–air, possesses a good potential with 8470 Wh/kg theoretical specific energy to play a major role (at least) in the primary battery market due to utilizing the second most abundant element in the Earth’s crust as an anode material. The aim of this thesis is to investigate and obtain new insights into understanding of the mechanisms taking place within the Si–air batteries which, eventually, could lead to further developments. In this regard, the first part of this work considers the non-aqueous Si–air batteries independently from the rest which focus on the aqueous alkaline electrolyte. The non-aqueous Si–air batteries employing fluorohydrogenated room temperature ionic liquid (EMIm(HF)2.3F) are investigated in order to understand the influence of Si anodes specifications on the battery performance. The study is focused on three different types of dopants namely, As, Sb, and B, as well as with and crystal orientations in each case. Discharge experiments are performed at various current densities and corrosion rates are obtained by mass loss calculations in combination with potentiodynamic polarization experiments. The results confirmed that there are at least two different corrosion mechanisms existing and potentiodynamic polarization experiments are not sufficient alone to quantify them. Furthermore, the most suitable Si anode type is discussed by considering the mass conversion efficiencies and specific energies while taking the consumed anode mass into account. For aqueous alkaline Si–air batteries, at first, the corrosion behavior of highly As-doped oriented silicon wafers are investigated with respect to (i) time dependence, (ii) influence of KOH concentration, and (iii) chemical vs. electrochemical corrosion. Corrosion rates are found to exhibit stable time profiles for immersion times longer than 8 h. With respect to concentration dependence, three ranges of KOH concentrations were identified; within each range, the corrosion behavior is governed by similar mechanisms, but different limiting factors. Potentiodynamic experiments showed that large part of the corrosion is chemical in nature. As a first step for an understanding of the corrosion during discharge, the impact of the OH- concentrations on the anodic currents are investigated by means of cyclic voltammograms in half-cells. The current state-of-the-art alkaline Si–air battery is limited in discharge time to few minutes when a Si anode with a plane surface is employed. Thereby, in the second part of the investigations for aqueous alkaline Si–air batteries, the discharge behavior of Si–air cells with KOH electrolyte is reconsidered and a new cell setup is designed to put forward the discharge process until the complete anode is exhausted. Discharging Si–air cells enhanced the corrosion rates depending on the current densities and KOH concentrations. Along with the corrosion and discharge of Si in KOH, condensation of silicate structures in the electrolyte has been observed. Both effects accelerate electrolyte loss in the cell; therefore, appropriately balancing the electrolyte supply of the Si–air battery is a precondition for ongoing discharge. Specifically, cells with As-doped Si anodes with 0.6 mm and 3.0 mm thickness were discharged in 5 M KOH electrolyte at current densities up to 0.05 mA/cm2 for 260 and 1100 hours, respectively. Although a considerable fraction of the anode material is not transformed to electrical energy owing to corrosion, specific energies up to 140 Wh/kg (for 1100 h) related to the total anode mass loss are realized

Investigation and development of a resource efficient metal-air battery – silicon-air

Interest on metal–air batteries has been emerging due to increased demand on resource efficient battery technologies and development of materials. By possessing high theoretical specific energies as well as using low cost, safe and abundant electrode materials, metal–air batteries are promising energy storage devices which could fulfill the current demands. A recent concept of metal–air batteries, Si–air, possesses a good potential with 8470 Wh/kg theoretical specific energy to play a major role (at least) in the primary battery market due to utilizing the second most abundant element in the Earth’s crust as an anode material. The aim of this thesis is to investigate and obtain new insights into understanding of the mechanisms taking place within the Si–air batteries which, eventually, could lead to further developments. In this regard, the first part of this work considers the non-aqueous Si–air batteries independently from the rest which focus on the aqueous alkaline electrolyte. The non-aqueous Si–air batteries employing fluorohydrogenated room temperature ionic liquid (EMIm(HF)2.3F) are investigated in order to understand the influence of Si anodes specifications on the battery performance. The study is focused on three different types of dopants namely, As, Sb, and B, as well as with and crystal orientations in each case. Discharge experiments are performed at various current densities and corrosion rates are obtained by mass loss calculations in combination with potentiodynamic polarization experiments. The results confirmed that there are at least two different corrosion mechanisms existing and potentiodynamic polarization experiments are not sufficient alone to quantify them. Furthermore, the most suitable Si anode type is discussed by considering the mass conversion efficiencies and specific energies while taking the consumed anode mass into account. For aqueous alkaline Si–air batteries, at first, the corrosion behavior of highly As-doped oriented silicon wafers are investigated with respect to (i) time dependence, (ii) influence of KOH concentration, and (iii) chemical vs. electrochemical corrosion. Corrosion rates are found to exhibit stable time profiles for immersion times longer than 8 h. With respect to concentration dependence, three ranges of KOH concentrations were identified; within each range, the corrosion behavior is governed by similar mechanisms, but different limiting factors. Potentiodynamic experiments showed that large part of the corrosion is chemical in nature. As a first step for an understanding of the corrosion during discharge, the impact of the OH- concentrations on the anodic currents are investigated by means of cyclic voltammograms in half-cells. The current state-of-the-art alkaline Si–air battery is limited in discharge time to few minutes when a Si anode with a plane surface is employed. Thereby, in the second part of the investigations for aqueous alkaline Si–air batteries, the discharge behavior of Si–air cells with KOH electrolyte is reconsidered and a new cell setup is designed to put forward the discharge process until the complete anode is exhausted. Discharging Si–air cells enhanced the corrosion rates depending on the current densities and KOH concentrations. Along with the corrosion and discharge of Si in KOH, condensation of silicate structures in the electrolyte has been observed. Both effects accelerate electrolyte loss in the cell; therefore, appropriately balancing the electrolyte supply of the Si–air battery is a precondition for ongoing discharge. Specifically, cells with As-doped Si anodes with 0.6 mm and 3.0 mm thickness were discharged in 5 M KOH electrolyte at current densities up to 0.05 mA/cm2 for 260 and 1100 hours, respectively. Although a considerable fraction of the anode material is not transformed to electrical energy owing to corrosion, specific energies up to 140 Wh/kg (for 1100 h) related to the total anode mass loss are realized