batterydata/paper-abstracts huggingface dataset:
Accurate measurement of CD4 cell counts remains an important tenet of clinical care for people living with HIV. We assessed an instrument-free point-of-care CD4 test (VISITECT® CD4) based on a lateral flow principle, which gives visual results after 40 min. The test involves five steps and categorises CD4 counts as above or below 350 cells/μL. As one component of a performance evaluation of the test, this qualitative study explored the views of healthcare workers in a large women and children’s hospital on the acceptability and feasibility of the test.
We propose a novel surfactant-mediated process to fabricate flexible microsupercapacitors (MSCs) combining conventional photolithography and electrochemical deposition. The anionic surfactant mediates the process of electropolymerisation at a lower anodic potential while causing template effects in producing porous conducting poly(3,4-ethylenedioxythiophene) (PEDOT) electrodes. Using this strategy, PEDOT MSCs with remarkable performance in terms of tunable frequency response and energy density are achieved. Specifically, ultrahigh scan rate capability up to 500V/s is achieved with a crossover frequency of 400Hz at a phase angle of −45°. This is the first polymer-based redox microsupercapacitor with excellent frequency characteristics other than carbonaceous-based electrochemical double layer capacitors reported so far in the literature. Thus, the micro-supercapacitors exhibit maximum areal cell capacitance of 9mF/cm2 with a volumetric stack capacitance of 50F/cm3 in 1M H2SO4 aqueous electrolyte. The flexibility and stability of these PEDOT MSCs is tested in aqueous gel electrolyte which showed a capacitance retention up to 80% over 10,000 cycles with a Coulombic efficiency of 100%. The maximum energy density of solid state ion gel based PEDOT MSCs was found to be 7.7mWh/cm3, which is comparable to the lithium based thin film batteries and superior to the current state-of-the-art carbon and metal oxide based MSCs. Further, the tandem configuration of flexible solid state ion gel based PEDOT MSCs is employed to demonstrate it as a power source for glowing a red light emitting diode.
In the first part of this work, we propose dissipative cell equalization (DCE) algorithm based on remaining charging capacity estimation (RCCE) and establish a pack model with 8 cells in series. The results show that RCCE-DCE algorithm is suitable for on-line equalization in electric vehicles (EVs) and no over-equalization happens. However, 1% pack capacity difference from the DCE theoretical pack capacity is observed with RCCE-DCE algorithm. Therefore, as the second part of the series, we propose fuzzy logic (FL) DCE algorithm based on charging cell voltage curves (CCVCs). Cell capacities and SOCs are fuzzily identified in FL-DCE algorithm by comparing cell voltages at the beginning and end of charging. Adaptive FL-DCE is further improved to prevent over-equalization and maintain the equalization capability. The simulation results show that pack capacity difference from the DCE theoretical pack capacity with the adaptive FL-DCE is smaller than that with RCCE-DCE algorithm, and the duration of the infant stage is also shorter. The proposed adaptive FL-DCE is suitable for on-line equalization in EVs and well prevents over-equalization.
Fe3O4-based Cu nanostructured electrodes for Li-ion cells are fabricated by a two-step electrochemical process. Cu nanorod arrays acting as current collectors are first prepared on a thin copper disk by alumina template-assisted electrodeposition. The active material of Fe3O4 is electrochemically deposited onto the Cu nanorod arrays by potentiostatic deposition. X-ray diffraction identifies textured growth for both the Cu nanorods and Fe3O4. Scanning electron microscopic observation further reveals that the active material are deposited between the Cu nanorods, and a 30s deposition of Fe3O4 is sufficient to fill up the inter-rod space under the currently employed condition. Longer electroplating time leads to the coalescence of Fe3O4 particles and the formation of bulky Fe3O4 islands on the top of the Cu nanorods. Electrochemical properties of the nanostructured electrodes are studied by conventional charge/discharge tests. The results show that the rate capabilities of the nanostructured electrodes are better compared to those of the planar electrodes and the coalescence of Fe3O4 particles is detrimental to achieve sustained reversible capacities.
The hydroxyl groups in inorganic-organic hybrid poly (cyclotriphosphazene-co-4,4-sulfonyldiphenol) (PZS) exhibits some reactivity toward lithium ions. In this work, the core-shell structured silica-poly (cyclotriphosphazene-co-4,4′-sulfonyldiphenol) nanoparticles (SiO2-PZS) are synthesized and the composite separator is prepared by coating on both sides of polyethylene (PE) microporous membrane. Compared to pure SiO2 coated separator and PE membrane, the PE-SiO2@PZS separator shows higher ionic conductivity. The corresponding discharge capacity at 8C rate reaches a value of 115 mA h g−1, compared to 105 mA h g−1 for PE membrane and 106 mA h g−1 for PE-SiO2 separator. The hydroxyl group and N、O atoms on the surface of PZS can coordinate with lithium ions to enhance the dissociation of lithium salt (LiPF6), thus improving the ionic conductivity and discharge capacity. Meanwhile the lower interfacial impedance resistance for PE-SiO2@PZS separator indicates intimate adhesion between electrode and separator. In a word, the SiO2-PZS nanoparticles are a promising filler for enhancing the wettability and electrochemical performance of Lithium-ion battery separator.
To improve the safety of lithium-ion batteries (LIBs), co-polyimide (PI) P84 was introduced as a polymeric binder for Al2O3/polymer composite surface coatings on polypropylene (PP) separators. By monitoring the dimensional shrinkage of the PP separators at high temperatures, we verified a synergistic thermal stabilization effect between the Al2O3 ceramic and the PI polymeric binder. Although PI was thermally stable up to 300 °C, a coating consisting solely of PI did not impede the PP separator dimensional changes (−22% at 150 °C). On the other hand, the Al2O3/PI-coated PP separators efficiently impeded the thermal shrinkage (−10% at 150 °C). In contrast, an Al2O3/poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) combination lowered the thermal stability of the PP separators (−33% at 150 °C). As a result, the Al2O3/PI-coated PP separators remarkably suppressed the internal short-circuit of the unit half-cells associated with separator thermal shrinkage (100 min at 160 °C), whereas the PVdF-HFP retained only 40 min under identical conditions. The Al2O3/PI-coated PP separators achieved rate capabilities and cell performances similar to those of the bare PP separators.
The effects of adding potassium ion (K+) to lithium oxalyldifluroborate (LiODFB)/ethylene carbonate (EC)+dimethyl carbonate (DMC) (1:1 vol.%) electrolyte on the cycle behaviors of lithium deposition–stripping on a Li22Sn5 substrate electrode are investigated. The functions and mechanism of K+ addition to the electrolyte are evaluated through scanning electron microscopy (SEM), inductively coupled plasma-atomic emission spectrometry (ICP–AES), element mapping, energy dispersive spectrometer (EDS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) analyses. The addition of K+ to the electrolyte significantly improves the morphology of the lithium deposits and the cycleability of lithium deposition–stripping. K+ is not reduced nor incorporated on the substrate during lithium deposition. Based on the reported “self-healing electrostatic shield” (SHES) mechanism, this study proposes the SHES–kinetics mechanism, which considers both kinetic and thermodynamic factors.
Each year, more than 200 million children under the age of 5 years, almost all in low- and middle-income countries (LMICs), fail to achieve their developmental potential. Risk factors for compromised development often coexist and include inadequate cognitive stimulation, poverty, nutritional deficiencies, infection and complications of being born low birthweight and/or premature. Moreover, many of these risk factors are closely associated with newborn morbidity and mortality. As compromised development has significant implications on human capital, inexpensive and scalable interventions are urgently needed to promote neurodevelopment and reduce risk factors for impaired development.
Aim Cognitive deficits in type 2 diabetes mellitus (T2DM) may be partly attributable to stiffness in cerebral arteries and impaired vasodilator function, limiting the ability to increase blood flow in brain regions to meet cognitive demands. We undertook a comparison of cerebrovascular responsiveness (CVR) and cognitive performance in adults with and without T2DM. Methods Older adults with (50) and without (Herath, Cherbuin, Eramudugolla, & Anstey, 2016) T2DM underwent transcranial Doppler ultrasound measurements of basal cerebral mean blood flow velocity (MBFV) and pulsatility index (PI), a measure of arterial stiffness, in the middle cerebral arteries (MCA). A battery of tasks assessing domains of working memory, executive function and information processing/motor speed was then administered while MBFV was recorded. CVR to cognitive tasks was calculated as a percentage increase in MBFV from the basal level. Results There was no difference in basal MBFV between groups. However, PI was 14% higher in the T2DM group (P <0.05), who performed poorer across all cognitive domains assessed and displayed poorer CVR in three tasks. Cognitive performance was inversely related to the PI/MBFV ratio, an indicator of intracranial stenosis. Discussion Impaired cerebral perfusion during mental tasks is accompanied by poor cognitive performance and stiffness in the cerebral vessels.
Thermal reactions between cathode particles (LiNi0.8Co0.2O2, LiCoO2, LiMn2O4 and LiFePO4) and ternary electrolyte (1.0M LiPF6 in 1:1:1 diethyl carbonate/dimethyl carbonate/ethylene carbonate) with or without the thermal stabilizing additive dimethyl acetamide (DMAc) have been investigated. Ternary electrolyte reacts with the surface of lithiated metal oxides (LiNi0.8Co0.2O2, LiCoO2 and LiMn2O4) upon storage to corrode the surface and generate a complex mixture of organic and inorganic surface species, but the bulk ternary electrolyte does not decompose. There is little evidence for reaction between the surface of carbon coated LiFePO4 and ternary electrolyte upon storage at elevated temperature (>60°C), but the bulk ternary electrolyte decomposes. Addition of DMAc to ternary electrolyte reduces the surface corrosion of the lithiated metal oxides and stabilizes the electrolyte in the presence of LiFePO4.
In addition to the occurrence of numerous neurofibrillary tangles and Aβ plaques, neurogenesis and neuronal plasticity are markedly altered in Alzheimer disease (AD). Although the most popular therapeutic approach has been to inhibit neurodegeneration, another is to promote neurogenesis and neuronal plasticity by utilizing the regenerative capacity of the brain. Here we show that, in a transgenic mouse model of AD, 3xTg-AD mice, there was a marked deficit in neurogenesis and neuroplasticity, which occured before the formation of any neurofibrillary tangles or Aβ plaques and was associated with cognitive impairment. Furthermore, peripheral administration of Peptide 6, an 11-mer, which makes an active region of ciliary neurotrophic factor (CNTF, amino acid residues 146–156), restored cognition by enhancing neurogenesis and neuronal plasticity in these mice. Although this treatment had no detectable effect on Aβ and tau pathologies in 9-month animals, it enhanced neurogenesis in dentate gyrus, reduced ectopic birth in the granular cell layer, and increased neuronal plasticity in the hippocampus and cerebral cortex. These findings, for the first time, demonstrate the possibility of therapeutic treatment of AD and related disorders by peripheral administration of a peptide corresponding to a biologically active region of CNTF.
This work evaluates the performance of a plug-in hybrid electric vehicle (PHEV) energy management process that relies on the active management of the degradation of its energy carriers – in this scenario, a lithium-ion battery pack and a polymer electrolyte membrane fuel cell (PEMFC) – to produce a near economically-optimal vehicle operating profile over its entire useful lifetime. This solution is obtained through experimentally-supported PHEV models exploited by an optimal discrete dynamic programming (DDP) algorithm designed to efficiently process vehicle usage cycles over an extended timescale. Our results demonstrate the economic and component lifetime gains afforded by our strategy when compared with alternative rule-based PHEV energy management benchmarks.
Modern Water Plc, which owns, installs and operates membrane-based systems, and develops and supplies technology for monitoring water quality, launched the latest version of its PDV6000 trace metal monitor at the Water, Wastewater and Environmental Monitoring (WWEM) exhibition, which was held during November in Telford, UK.
Objective To prospectively evaluate for changes in objective cognitive performance (attention, memory, and executive function) and psychiatric symptom severity (depression, anxiety, fatigue, and pain) in patients before, during and after interferon-alpha based therapy (IFN) for chronic hepatitis C virus infection (HCV). Methods 33 HCV+ adults were evaluated two months before IFN initiation (baseline), three months into IFN, and six months following IFN termination (IFN+ Group). 31 HCV+ adults who did not undergo IFN therapy were evaluated at baseline and six months later (IFN− Group). At each evaluation, participants completed the Neuropsychological Assessment Battery (NAB) Attention, Memory and Executive Functions Modules, the Beck Depression Inventory, Second Edition (BDI), Generalized Anxiety Disorder Inventory (GADI), Fatigue Severity Scale (FSS), and Brief Pain Inventory (BPI). Results Compared with the IFN− Group, the IFN+ Group experienced significantly (p<0.050) increased symptoms of depression, anxiety, fatigue and pain during IFN therapy relative to baseline. In the IFN+ Group, psychiatric symptoms generally returned to baseline levels following IFN termination. Sustained viral response was associated with significantly lower depression and fatigue. No significant changes in cognitive performance were observed. Conclusions During IFN, patients with HCV evidence significantly increased psychiatric symptoms, including symptoms of depression, anxiety, fatigue and pain. These psychiatric symptoms are generally short-term and remit following IFN termination, with increased benefit if viral clearance is achieved. However, IFN is not associated with significant declines in objective cognitive performance during or following IFN.
Background Gastroparesis is a recognized complication following organ transplantation with incidences reported between 24 and 83%. Gastroparesis can complicate medical management in these patients leading to the inability to take medications and possibly chronic transplant rejection. Gastric electrical stimulation (GES) has been shown in both controlled and uncontrolled studies to reduce the frequency of nausea and vomiting and lead to weight gain in patients with gastroparesis refractory to standard medical treatment; however, there is little evidence to support the use of GES in transplant recipients. The goal was to evaluate the response of transplant patients with gastroparesis to GES and compare to nontransplant recipients. Materials and methods A questionnaire consisting of 11 questions was administered to investigate symptoms. Patients were asked to score these symptoms before and after surgery using a 0-5 Likert scale. Results Thirteen consecutive patients underwent placement of the Enterra (Medtronic, Minneapolis, MN) device with a mean follow-up of 12 ± 6.1 months. All three transplant patients (100%) reported an improvement in quality of life. Similarly, transplant patients were as likely as the diabetic or idiopathic patients to demonstrate improvements in symptoms of nausea, vomiting, and retching and prandial symptoms following Enterra therapy. In fact, transplant patients reported improvement in appetite and bloating symptoms more frequently than diabetics (P = 0.055 and P = 0.037, respectively). Conclusion Posttransplantation gastroparesis responds to therapy with Enterra GES as well as in patients with idiopathic or diabetic gastroparesis. Enterra therapy should be prospectively investigated in this population of patients.
The present study evaluated cerebral lateralization during Raven’s progressive matrices (RPM) paradigm in female and male subjects. Bilateral simultaneous transcranial Doppler (TCD) ultrasound was used to measure mean blood flow velocities (MBFV) in the right and left middle cerebral arteries (MCAs) in 24 (15 females and 9 males) right-handed normal subjects. The female subjects used a left hemisphere strategy, while males used a right hemisphere strategy to successfully solve RPM tasks. This implies that general intelligence is associated with neural systems within one hemisphere that are accessible to a variety of cognitive processes.
The composite cathode materials of LiFePO4/C were synthesized by spray-drying and post-annealing method. The crystalline structure and morphology of products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The charge–discharge kinetics of LiFePO4/C electrode was investigated using electrochemical impedance spectroscopy (EIS). The results show that the increment of the resistance has a close relation to the appearance of the FePO4 phase during charge–discharge course, and that the ohmic resistance, charge transfer resistance and lithium-ion diffusion coefficients of the LiFePO4/C electrode do not change much by extended cycling tests, implying a relatively superior cyclability of the battery. The effect of cell temperature on the electrochemical reaction behaviors of LiFePO4/C electrode was also investigated using the EIS. It is confirmed that the effect of the cell temperature on the impedance results mainly from the enhancement of the lithium-ion diffusion at elevated temperatures.
A macromolecule plasticized interpenetrating polymer networks (IPNs) polymer is attempted to develop solid-state polymer electrolyte for lithium-ion batteries. This IPN polymer electrolyte membrane is prepared by a simple in situ UV-curing method, using PEG350mA, PEG200diA, plasticizer and LiClO4 mixture as starting materials. The plasticizer, a six-arm star macromolecule SM400, which is synthesized from phloroglucinol, phosphorus oxychloride and methyl polyethylene glycol (MPEG, M w =400), is found to be effective to improve the ionic conductivity of the IPN electrolytes. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR), electrochemical impedance spectroscopy (EIS) are used to characterize the IPN based solid state polymer electrolytes. The electrolyte of SM400 (30wt.%)–IPN–LiClO4 (5wt.%) shows the ionic conductivity of 6.06×10−5 Scm−1 at room temperature. A Li/SPEs/LiFePO4 coin cell shows acceptable charge/discharge performance. The proposed attempt paves a potential way to develop solid state polymer electrolytes for Li-ion batteries.
In a global environment context in which the urgent need to reduce pollutant emissions is of central relevance, it is becoming increasingly important the research for solutions, concerning the vehicular transport sector with low environmental impact. Fuel cell technology is expected to become a viable solution for these applications due to its environmental friendly characteristics. The present study concerns the traction system of a bus considering the case of hybrid solutions consisting of a proton exchange membrane fuel cell (PEMFC) in parallel with a battery pack. In particular, a dynamic model of a PEMFC/battery system is presented for the application under study. The model incorporates the dynamics of the fuel cell and the state of charge (SOC) of the battery pack. The fuel cell and the battery output power have been determined according to the real driving load demand of a bus taking into consideration a daily operation of 12h. Such a model has allowed the correct dimensioning of the hybrid power system (giving a particular attention to the fuel cell and the hydrogen tank) together with the optimization of the SOC control strategy.
For its low redox potential (−3.04 V vs. SHE) and the high theoretical specific capacity (3860 mA h g−1), lithium metal is regarded as one of the most promising anode materials for next-generation batteries. However, the poor cycling performances and serious safety hazards caused by the inhomogeneous lithium deposition severely hinder the practical applications of Li metal batteries. Here, we introduce 3-D carbon materials which are subsequently in-situ transformed into LiC6 as electrode scaffold. Such lithiophilic 3-D structure with a high specific surface area enables dendrite-free deposition of Li metal, resulting in a high coulombic efficiency up to 97% after 300 cycles. We propose that besides 3-D structure, LiC6 intermediate may be responsible for the dendrite-free growth of Li, offering a potential new strategy to design high performance anodes for Li metal batteries.
In this study, we analyzed the thermal characteristics of commercial cylindrical lithium-ion cells using an accelerated rate calorimeter (ARC) and by analyzing the electrochemical impedance spectroscopy (EIS) measurements. During the thermal runaway analysis, the cells were tested at different state of charges (SOCs) and the thermal deterioration was determined by monitoring the impedance at 1kHz and the open circuit voltage as a function of the temperature. The mapping of the thermal runaway was obtained, ant the non-self heating, self-heating and thermal runaway regions were identified at different SOCs. The self-heating and thermal runaway behaviors showed a temperature dependence. In order to clarify the deterioration reaction in the non-self heating region, high temperature storage tests were carried out, storing the cell in the temperature range of 70–100°C. We estimated the activation energy from the discharge capacities before and after the high temperature storage. In order to determinate the charge/discharge activation energy of the cells, EIS measurements were recorded. Based on our study, the activation energy of the deterioration was about two times greater in magnitude than the activation energy of the charge/discharge.
To examine the feasibility of a solid oxide fuel cell (SOFC)-powered unmanned undersea vehicle (UUV), a system level analysis is presented that projects a possible integration of the SOFC stack, fuel steam reformer, fuel/oxidant storage and balance of plant components into a 21-in. diameter UUV platform. Heavy hydrocarbon fuel (dodecane) and liquid oxygen (LOX) are chosen as the preferred reactants. A maximum efficiency of 45% based on the lower heating value of dodecane was calculated for a system that provides 2.5kW for 40h. Heat sources and sinks have been coupled to show viable means of thermal management. The critical design issues involve proper recycling of exhaust steam from the fuel cell back into the reformer and effective use of the SOFC stack radiant heat for steam reformation of the hydrocarbon fuel.