batterydata/paper-abstracts huggingface dataset:
Membrane potentials and brain plasticity are basic modes of cerebral information processing. Both can be externally (non-invasively) modulated by weak transcranial direct current stimulation (tDCS). Polarity-dependent tDCS-induced reversible circumscribed increases and decreases in cortical excitability and functional changes have been observed following stimulation of motor and visual cortices but relatively little research has been conducted with respect to the auditory cortex. The aim of this pilot study was to examine the effects of tDCS on auditory sensory discrimination in healthy participants (N = 12) assessed with the mismatch negativity (MMN) brain event-related potential (ERP). In a randomized, double-blind, sham-controlled design, participants received anodal tDCS over the primary auditory cortex (2 mA for 20 min) in one session and ‘sham’ stimulation (i.e., no stimulation except initial ramp-up for 30 s) in the other session. MMN elicited by changes in auditory pitch was found to be enhanced after receiving anodal tDCS compared to ‘sham’ stimulation, with the effects being evidenced in individuals with relatively reduced (vs. increased) baseline amplitudes and with relatively small (vs. large) pitch deviants. Additional studies are needed to further explore relationships between tDCS-related parameters, auditory stimulus features and individual differences prior to assessing the utility of this tool for treating auditory processing deficits in psychiatric and/or neurological disorders.
Objective This cross-sectional study explored the relationships between daily activity performance, attention, memory, executive functions and community functioning in people with schizophrenia. More specifically, this study attempted to verify the hypothesis that functional limitations in the performance of daily activities negatively affect community functioning in people with schizophrenia. Methods Eighty-two individuals with schizophrenia living in the community were recruited for the study. The Perceive, Recall, Plan and Perform (PRPP) System of Task Analysis was used to assess participants’ functional capacity during a meal preparation task. Visuo-spatial associative memory, spatial working memory, planning, visuo-motor coordination, and selective attention were evaluated as well. Community functioning was assessed with the Independent Living Skills Survey (ILSS) and the Multnomah Community Ability Scale (MCAS). Results Correlations revealed significant associations between functional capacity and visuo-spatial associative learning, spatial working memory, planning and negative symptoms. Planning skills during meal preparation were found to be associated with MCAS. After regression analyses, only visuo-spatial memory, negative symptoms, education and familiarity with meal preparation explained variation in functional capacity. Conclusions The findings of the current study suggest that visuo-spatial associative learning, negative symptoms, education and familiarity with task are among the important factors for functional capacity. Planning skills necessary for efficient task performance were also found to be those most determinant for community functioning. Rehabilitation interventions should consider these underlying strength and deficits when developing strategies to help people with schizophrenia build functional skills essential for community living.
This paper focuses on the emergence of spiral waves in a specific morpho-electrochemical reaction-diffusion model on a sphere. This study fits in the framework of the morphological control of material electrodeposited onto spherical particles that is crucial to the energetic efficiency of the recharge process as well as to the durability of energy storage devices. The spherical geometry for the electrode surface is of notable practical interest since spheres are the shape of choice for flow batteries and metal-air devices [35]. Motivated by this technological framework, in this paper we extend the results on pattern formation in [27] to include investigations on the spiral wave phenomenology. We show that spiral waves emerge because of the interplay between two specific model parameters: one regulating the oscillatory dynamics in the kinetics and the other one related to the domain size. We present systematic numerical simulations based on the finite element method LSFEM [45,50] accompanied by the computation of suitable indicators that allow to characterize and compare the spatio-temporal features. Interestingly, the model also supports a mechanism of spirals break up leading to a complex spatio-temporal phenomenology. The findings of our study have been validated with experimental results on Ag-In and Ag-Co electrodeposition.
All-solid-state polymer electrolyte (SPE) matrices prepared by molecular design are still needed to be further perfected with excellent performance. In this paper, a controlled-structure discotic liquid crystal (DLC)-based six-arm star copolymer was designed and synthesized from a DLC initiator (2,3,6,7,10,11-hexakis(2-bromoisobutyryloxy)triphenylene) via the sequential atom transfer radical polymerization (ATRP) of styrene and poly(ethylene glycol) methyl ether methacrylate (PEGMA). Here, this class of discotic liquid crystal star polymer is applied as an SPE in LIBs for the first time. By solution casting, a suitable self-standing SPE film composed of the six-arm copolymer and lithium bis(trifluoromethanesulfonimide (LiTFSI)) can be easily formed, and the film shows long-range molecular orientation after annealing. It is confirmed that the electrolyte shows wide electrochemical window (5.1 V) and high lithium-ion transference number (0.37). Especially, the ionic conductivity (1.46 × 10−4, S cm−1, 30 °C) of the obtained SPE is more than 8 times higher than that of the corresponding linear copolymer electrolytes. Furthermore, the results of battery performance demonstrate that the polymer electrolyte displays eminently reversible electrochemical reaction and outstanding cycling performance. The present work not only shows the advantages of DLC-based star SPE for LIBs but also paves the way for the design of SPE with excellent performances.
To improve the cycling performance of spinel LiMn2O4, Al-doped LiMn2O4, LiAl0.1Mn1.9O4, is synthesized using Mn1.9Al0.1O3 precursor and LiOH·H2O via a low temperature solid-phase reaction. The Mn1.9Al0.1O3 precursor, prepared from the electrolytic manganese dioxide (EMD) and Al(OH)3, is composed of spherical particles with an average diameter of 300nm, and has a large interspace. Energy dispersive spectrometer (EDS) indicates the Al element is well distributed in Mn1.9Al0.1O3 and LiAl0.1Mn1.9O4. The scanning electron microscopy (SEM) and transmission electron microscope (TEM) images show that the LiAl0.1Mn1.9O4 sample has a high crystallinity with sizes ranging from 300 to 500nm. Electrochemical properties of LiAl0.1Mn1.9O4 are studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge. The results show that LiAl0.1Mn1.9O4 possesses better rate and cycling capabilities than LiMn2O4 at both 25°C and 55°C. At a rate of 5C, the capacity retention ratio of the LiMn1.9Al0.1O4 electrode after 100 cycles is about 95% at 25°C and about 90% at 55°C.
ABSTRACT The use of air conditioning for vehicles in hot climates is a significant contributor to both overall fuel consumption and tailpipe emissions. It can be seen, however, that much of the energy required by the air conditioning goes not into cooling the occupants but cooling the vehicle structure. Most air conditioning loads are highest after the vehicle has soaked in the sun for a period of time. Consequently, the focus must be on limiting heat penetration into the vehicle in order to reduce the peak and steady state cooling loads. For this paper a modelling approach is used to assess the impact of various palliative countermeasures. A Radtherm heat transfer model was constructed for a saloon type vehicle to mimic a solar soak and subsequent pull-down for a simulated climatic chamber test. The base vehicle air conditioning load was identified before various material changes to the vehicle structure were implemented. The impact of each, and the results for an optimum combination, is presented in terms of average interior air and selected component surface temperatures at the end of the soak and pull-down periods. Additionally, the impact of forced ventilation pre-conditioning for the soak period, as may be driven by an integrated solar panel, was also investigated.
Tidal marsh functions are driven by interactions between tides, landscape morphology, and emergent vegetation. Less often considered are the diurnal pattern of tide extremes and seasonal variation of solar insolation in the mix of tidal marsh driver interactions. This work demonstrates how high-frequency hydroperiod and water temperature variability emerges from disparate timescale interactions between tidal marsh morphology, tidal harmonics, and meteorology in the San Francisco Estuary. We compare the tidal and residual flow and temperature response of neighboring tidal sloughs, one possessing natural tidal marsh morphology, and one that is modified for water control. We show that the natural tidal marsh is tuned to lunar phase and produces tidal and fortnight water temperature variability through interacting tide, meteorology, and geomorphic linkages. In contrast, temperature variability is dampened in the modified slough where overbank marsh plain connection is severed by levees. Despite geomorphic differences, a key finding is that both sloughs are heat sinks in summer by latent heat flux-driven residual upstream water advection and sensible and long-wave heat transfer. The precession of a 335-year tidal harmonic assures that these dynamics will shift in the future. Water temperature regulation appears to be a key function of natural tidal sloughs that depends critically on geomorphic mediation. We investigate approaches to untangling the relative influence of sun versus tide on residual water and temperature transport as a function of system morphology. The findings of this study likely have ecological consequences and suggest physical process metrics for tidal marsh restoration performance.
A sensing platform with NiFe2O4 nanoparticles integrated into carbon paste for the electrochemical determination of nitrite has been developed. Spinel NiFe2O4 nanoparticles were synthesised via a simple solvent deficient method and investigated by X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and Scanning electron microscopy (SEM), for their structural and morphological characteristics. The NiFe2O4 integrated carbon paste electrode (NiFe2O4-CPE) displayed enhanced catalytic activity towards oxidation of nitrite than the bare electrode in phosphate buffer solution (PBS) of pH-7 owing to the synergistic effect arising from the mixed metals. The electrochemical response of NiFe2O4-CPE under the influence of several parameters such as effect of scan rate, catalyst-carbon ratio and the concentration of analyte was studied. The oxidation of nitrite was found to be a diffusion controlled process as the oxidation currents varied linearly with scan rate and concentration of the analyte. The diffusion coefficient and rate constant for nitrite oxidation was found to be 3.71 × 10−5 cm2 s−1 and 9 × 108 cm3 mol−1 s−1 respectively. The sensing platform demonstrated a nitrite detection limit of 0.1236 μM (S/N = 3) with a wide linear range between 0.1 and 1000 μM and a sensitivity of 7.9617 μA μM−1 cm−2.
Hierarchical dumbbell-shaped lithium iron phosphate (LiFePO4) mesocrystals were successfully fabricated via a simple one-step, rapid, additive-free solvothermal route. A mixture of dimethylformamide/ethylene glycol (DMF/EG) has been utilized as the co-solvent and found to play an important role in the formation of the hierarchical mesostructure. The obtained dumbbell-shaped mesocrystals consist of self-assembly LiFePO4 nanorods each with 2–3 μm in length and 30–50 nm in diameter. Further temperature treatment was applied to increase the crystallinity of the LiFePO4 mesocrystals. A high lithium ion intercalation capacity of 140 mA h g−1 was exhibited by the LiFePO4 mesocrystal when tested under a discharge rate of 17 mA g−1, which should be attributed to the fast intercalation reaction and easy mass and charge transfer offered by the large specific surface and short diffusion distance of dumbbell-shaped mesoporous composed of nano-sized LiFePO4 rods. The nanorods can be carbon coated in-situ by adding sucrose during the solvothermal process and the LiFePO4/C mesocrystals showed an improved electrochemical property at higher rates and good cyclic performance.
Eurasian Otter (Lutra lutra) surveys are commonly based on spraints (otter faeces) as an index of use intensity, habitat preference, and to a certain degree, population density. We were interested to know: (1) Does the number of fresh spraints correlate to the number of visits? (2) Can spraints be indicative of activity levels? (3) Is the absence of fresh spraints indicative of no visits? We used videotaping that provided a true picture of otter nocturnal activity at marking sites and compared our findings with the number of fresh spraints the following morning. This enabled us to correlate the number of spraints with the number of otter visits during the night and assess the validity of spraints as an activity index. We carried out a total of 59 videotaping nights and counted spraints in 29 sprainting sites between September 2002 and March 2004. We found a positive correlation between the proportion of nights a latrine was visited and the proportion of nights fresh spraints were deposited. The number of fresh spraints/night/site was positively correlated with the number of otter visits/night/site. Latrines visited on more nights had a higher number of fresh spraints per night visited. However, in about half the nights where no spraints were found, visits were recorded. Spraints are generally a good indicator of use intensity of a specific latrine and consequently a possible indicator of activity level and habitat preference. Understanding what determines scent-marking behaviour and its relationship to actual activity and presence can improve our ability to assess otter populations and design management protocols.
In cultured A6 monolayers from distal Xenopus kidney, external Ni2+ stimulated active Na+ uptake via the epithelial Na+ channel, ENaC. Transepithelial capacitance measurements ruled out exocytosis of ENaC-containing vesicles underlying the Ni2+ effect. Na+ current noise analysis was performed using the neutral Na+-channel blocker 6-chloro-3,5-diamino-pyrazine-2-carboxamide (CDPC) and amiloride. The analysis of CDPC-induced noise in terms of a three-state channel model revealed that Ni2+ elicits an increase in the number of open channels as well as in the spontaneous open probability. While Ni2+ had no influence on CDPC-blocker kinetics, the macroscopic and microscopic blocking kinetics of amiloride were affected. Ni2+ turned out to compete with amiloride for a putative binding site but not with CDPC. Moreover, external Na+—known to compete with amiloride and so producing the “self-inhibition” phenomenon—and Ni2+ exerted mutually exclusive analogous effects on amiloride kinetics. Na+ current kinetics revealed that Ni2+ prevents ENaC to be downregulated by self-inhibition. Co2+ behaved similarly to Ni2+, whereas Zn2+ did not. Attempts to disclose the chemical nature of the site reacting with Ni2+ suggested cysteine but not histidine as reaction partner.
Lithium-ion batteries are multiscale systems with processes occurring at different scales. We start from a mathematical model derived on the microscale level of a single battery cell [Latz et al., NMA’10, 2011, pp. 329–337] where we can resolve the porous structure of the electrodes. Direct numerical simulations on this scale lead to a huge number of degrees of freedom and, consequently, very high computational costs. From an application perspective, it is often sufficient to predict the macroscopic properties of the electrodes. Therefore, we derive homogenized macroscopic equations with effective transport coefficients for the concentration of lithium ions in the electrolyte, potential in the electrolyte, and potential in the solid particles. These upscaled equations are coupled via the Butler–Volmer interface conditions to a microscale equation for the concentration of lithium ions in the electrode particles. We follow the idea developed by Ciucci and Lai [Transport Porous Med 88(2):249–270, 2011] and extend their analysis by computing the asymptotic order of the interface exchange current densities, which is an important factor in the homogenization study of the problem. We also perform a numerical homogenization and run extensive numerical simulations in order to validate the derived upscaled model. The numerical experiments show very good agreement between the homogenized model and the microscale one. Hence we are able to predict the macroscopic properties of the porous electrodes and capture the small-scale effects on the large scales without fully resolving all the microscale features.
This paper presents an improved optimization method for sizing standalone photo-voltaic (PV) systems. Numerical methods for optimization and configuration of array size, charge controller, storage battery capacity, and power inverter of PVs are implemented using MATLAB and hourly meteorological data and load demand. DC voltage operation is also optimally selected. Loss of load probability analysis is conducted to set the benchmark for determining all possible PV arrays and battery capacities. Then, the optimum design is proposed based on the lowest levelized cost of energy and net present value. The case study refers to the meteorological data of Yemen and the typical load role of the domestic sector in Yemen. Results show that the net present value of 6.6024 kWh/day PV system for Yemen is 22224 USD, while the cost of energy generated by the proposed system is 0.403 USD/kWh and the loss of load probability ( L L P ) is equal to 0.130%.
The electrochemical performance of LiFePO4/C samples synthesized by different carbon sources varies considerably, the structural difference of residual carbon in LiFePO4/C accounts for the performance variation. Higher performance is associated with a larger ratio of graphitic carbon, which exhibits better electronic conductivity than amorphous carbon. To improve the electronic conductivity, we prepared LiFePO4/(C+G) composites by a one-step solid-state method, in which natural graphite is used as reducing agent and conducting additives. The samples were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), Raman microprobe spectroscope and other electrochemical methods. The results show that reversible capacity and rate performance of LiFePO4 are improved considerably by the two-phase carbon coating. Therefore, LiFePO4/(C+G) composites are a promising candidate for lithium ion batteries.
Budgets of nitrate, dissolved oxygen, and particulate organic carbon (POC) were constructed from data collected on-board a Lagrangian, profiling float deployed between April 4 and May 25, 2008, as part of the North Atlantic Bloom Experiment. These measurements were used to estimate net community production (NCP) and apparent export of POC along the float trajectory. A storm resulting in deep mixing and temporary suspension of net production separated the bloom into early (April 23–27) and main (May 6–13) periods over which ∼264 and ∼805mmolCm−2 were produced, respectively. Subtraction of the total POC production from the NCP yielded maximum estimates of apparent POC export amounting to ∼92 and 574 mmolCm−2 during the early and main blooms, respectively. The bloom terminated the following day and ∼282 mmolCm−2 were lost due to net respiration (70%) and apparent export (30%). Thus, the majority of the apparent export of POC occurred continuously during the main bloom and a large respiration event occurred during bloom Termination. A comparison of the POC flux during the main bloom period with independent estimates at greater depth suggest a rapid rate of remineralization between 60 and 100m. We suggest the high rates of remineralization in the upper layers could explain the apparent lack of carbon overconsumption (C:N>6.6) in the North Atlantic during the spring bloom.
Well-defined orthorhombic LiMnO2 was synthesized using LiOH and γ-MnOOH starting materials at 1000°C in an argon flow by quenching process. X-ray diffraction (XRD) revealed that the compound showed an orthorhombic phase of a space group with Pmnm (a=2.806 Å, b=5.750 Å, and c=4.593 Å). The prepared compound was composed of particles of about 5–15 μm diameter with a bar-shape and small spherical one of about 1–2 μm. It showed very small initial discharge capacity of about 34 mA h g−1 in the (3+4) V region at room temperature. However, after 12 h grinding, the LiMnO2 delivered 201 mA h g−1 in the first cycle and still delivered 200 mA h g−1 after 50 cycles at room temperature. We found that the initial discharge capacity of LiMnO2 agreed well with its specific surface area by Brunauer, Emmett and Teller (BET) analysis. Especially, the grinding treatment played an important role to activate the lithium insertion–extraction into the LiMnO2 layer in the 3 V region.
Presenting Author details:anabarajasvelez@hotmail.com C/Antoni Pujades, 42 (Sant Boi De Llobregat), 08830 Barcelona, Spain, Tel.: +34 6406350x2347; fax: +34 630 53 19. Background: Different studies of first psychotic episodes (FPE) have tried to describe the onset of psychosis. We examine whether FPE with onset during adolescence and childhood (ages 7–17) differ significantly from those with young–adult onset (ages 18–65) in neurological soft signs (NSS) and psychopathology; also, we assess if NSS are associated with negative psychotic symptoms and cognitive functioning in the onset of a FPE. Methods: Cross-sectional study of 28 consecutive cases with a FPE. Inclusion criteria: two or more psychotic symptoms; age range 7 to 65 years; first visit to a centre participating in the study; less than 6 months since first contact with services. Instruments used were a clinical and socio-demographic questionnaire, a battery assessing symptoms, and neurological evaluation scale (NES) and a battery of cognitive tests. Data were analyzed using the non-parametric Mann–Whitney U test and Spearman's correlations by the SPSS. Results: Age of onset distribution was 46.4% adult onset psychosis and 53.6% early onset psychosis having found significant differences between the two groups on measures of NES (p=0.019). NES total score correlates with negative symptoms (r=0.416; p=0.043) and cognitive variables: impulsivity (CPT index, r=0.443, p=0.044), executive functioning (Stroop Color–Word Test, r=−0.522, p=0.018; TMTB, r=−0.636; p=0.003) and working memory (subtests of WAIS/WISC: digit span, r=−0.54, p=0.014; arithmetic, r=−0.599, p=0.007; letter–number sequencing, r=−0.501, p=0.029). Conclusions: A higher level of neurobiological abnormalities in early onset of psychosis could underlie cognitive deficits, especially concerning attention, working memory and executive functioning, and may be related to a prominent negative symptomatology.
Bamboo-like carbon nanotubes containing sulfur (BCNT-S) were prepared through the carbonization and the activation of sulfonated polymer nanotubes in CO2. The BCNT-S showed a remarkably high specific capacitance of 259Fg−1 at the current density of 1Ag−1, while 97.7% of its initial capacitance was retained after 1000 cycles at the current density of 5Ag−1. In contrast, amorphous carbon without S had a specific capacitance of 129Fg−1 at 1Ag−1, which was only about half of that of the BCNT-S. Therefore, the introduction of a trace amount of sulfur (1.66%) could greatly enhance the specific capacitance of carbon nanotubes (CNTs). In addition, the high specific capacitance and excellent cycling stability of the BCNT-S were also benefited from its high specific surface area and bamboo-like tubular morphology.