The pattern‐reversal visual evoked potential (prVEP) is an established routine clinical test. Its objectivity is particularly valuable for assessing visual pathway function in children. International ...standards specify at a minimum that an active electrode is placed on the occiput at Oz, but we find an additional inferior electrode at the inion (Iz) provides larger and more sensitive prVEPs in young persons. This study assesses the significance and age‐dependence of these observations. PrVEPs were recorded from 1487 patients considered ophthalmologically normal aged <20 years old, to a range of check widths including International Society for Clinical Electrophysiology of Vision (ISCEV) standard large (50′) and small (12.5′) check widths. P100 peak‐time and amplitude from both electrode sites were analysed. A subset of 256 children were studied longitudinally by fitting logistic regression models including a random effect on subjects. PrVEPs were largest over the Iz electrode for the majority of infants and children. This transitioned with age to become equal or smaller at Oz as a function of check width. For ISCEV standard large and small check widths, transition periods were ∼8 and ∼12 years of age, respectively. We estimated abnormal result classifications of 3.7% with use of an Oz electrode alone, which decreases to 0.0–0.5% when adding or using an Iz electrode. The inferior dominance of prVEP topography in children may be explained by age‐related anatomical changes altering the cortical dipole, combined with physiological maturation of the neural generators of the prVEP. We recommend the Iz electrode is used routinely in recording of prVEPs in children.
Key points
Pattern visual evoked potentials (PVEPs) are an established clinical test which provide objective assessment of visual pathway function. These are particularly valuable in providing objective information of vision in children.
International standards specify the active recording electrode should be placed at the mid‐occiput (Oz), but we find that pattern‐reversal visual evoked potential amplitudes are larger for a lower placed electrode (Iz) in young persons.
This was assessed in 1487 patients who had simultaneous PVEP recording at both electrode positions, and it was found that the majority of PVEPs in children were larger over the Iz electrode.
The developmental differences in PVEP distribution transitioned to be equal between Iz and Oz with increasing age as a function of check width, at ∼8 and ∼12 years old for large and small check widths, respectively.
These differences will improve diagnostic accuracy of paediatric PVEPs. We hypothesise these changes reflect developmental anatomical and neurophysiological changes altering the PVEP dipole.
figure legend Schematic representation of prVEP response measurement. Responses were recorded from mid‐occipital (Oz) and inion (Iz) electrodes simultaneously, referred to a mid‐frontal electrode (Fz) and ground centrally (Cz). Peak‐time was taken from stimulus onset (0 ms) to peak of the P100 component (red dashed line). Amplitude was taken from the N75 trough to P100 peak (red vertical line).
► Review to study anthelmitics. ► Physicochemical properties, fate in the environment and ecotoxicity. ► Environmental levels of anthelmintics. ► Overview of analytical methodologies and sample ...preparation.
There has been a great effort made in recent years to study the fate, the occurrence and the ecotoxicology of emerging pollutants in the environment, with a particular emphasis on pharmaceuticals. Anthelmintics comprise a large sector of the animal pharmaceutical industry.
This article examines analytical methodologies for the analysis of anthelmintics and their transformation products (TPs) in the environment. It also gives a critical overview of the current knowledge on the fate and the ecotoxicology of anthelmintics and their TPs, if known.
Many neutron star properties, such as the proton fraction, reflect the symmetry energy contributions to the equation of state that dominate when neutron and proton densities differ strongly. To ...constrain these contributions at suprasaturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be 42<L<117 MeV. This value is slightly lower but consistent with the L values deduced from a recent measurement of the neutron skin thickness of ^{208}Pb.
In the Netherlands, maternity care is divided into midwife-led care (for low-risk women) and obstetrician-led care (for high-risk women). Referrals from midwife-led to obstetrician-led care have ...increased over the past decade. The majority of women are referred during their pregnancy or labour. Referrals are based on a continuous risk assessment of the health and characteristics of mother and child, yet referral for non-medical factors and characteristics remain unclear. This study investigated which maternal characteristics are associated with women's referral from midwife-led to obstetrician-led care.
A retrospective cohort study in one midwife-led care practice in the Netherlands included 1096 low-risk women during January 2015-17. The primary outcomes were referral from midwife-led to obstetrician-led care in (1) the antepartum period and (2) the intrapartum period. In total, 11 maternal characteristics were identified. Logistic regression models of referral in each period were fitted and stratified by parity.
In the antepartum period, referral among nulliparous women was associated with an older maternal age (aOR, 1.07; 95%CI, 1.05-1.09), being underweight (0.45; 0.31-0.64), overweight (2.29; 1.91-2.74), or obese (2.65; 2.06-3.42), a preconception period >1 year (1.34; 1.07-1.66), medium education level (0.76; 0.58-1.00), deprivation (1.87; 1.54-2.26), and sexual abuse (1.44; 1.14-1.82). Among multiparous women, a referral was associated with being underweight (0.40; 0.26-0.60), obese (1.61; 1.30-1.98), a preconception period >1 year (1.71; 1.27-2.28), employment (1.38; 1.19-1.61), deprivation (1.23; 1.03-1.46), highest education level (0.63; 0.51-0.80), psychological problems (1.24; 1.06-1.44), and one or multiple consultations with an obstetrician (0.68; 0.58-0.80 and 0.64; 0.54-0.76, respectively). In the intrapartum period, referral among nulliparous women was associated with an older maternal age (1.02; 1.00-1.05), being underweight (1.67; 1.15-2.42), a preconception period >1 year (0.42; 0.31-0.57), medium or high level of education (2.09; 1.49-2.91 or 1.56; 1.10-2.22, respectively), sexual abuse (0.46; 0.33-0.63), and multiple consultations with an obstetrician (1.49; 1.15-1.94). Among multiparous women, referral was associated with an older maternal age (1.02; 1.00-1.04), being overweight (0.65; 0.51-0.83), a preconception period >1 year (0.33; 0.17-0.65), non-Dutch ethnicity (1.98; 1.61-2.45), smoking (0.75; 0.57-0.97), sexual abuse (1.49; 1.09-2.02), and one or multiple consultations with an obstetrician (1.34; 1.06-1.70 and 2.09; 1.63-2.69, respectively).
This exploratory study showed that several non-medical maternal characteristics of low-risk pregnant women are associated with referral from midwife-led to obstetrician-led care, and how these differ by parity and partum period.
Background. Despite inadequate empirical validation, sit-to-stand (STS) performance is often used as a proxy measure of lower limb strength among older adults. Furthermore, the relationships between ...bilateral isokinetic hip, knee, and ankle joint strength and their contributions to STS performances among older adults have not been established. The authors evaluated these relationships on 2 STS tests (5-chair STS test and 30-second chair STS test) in sexagenarian women. Methods. 47 women (mean age, 64.50 years) performed both STS tests on the same day and bilateral isokinetic (60°/second) hip extensor, hip flexor, knee extensor, knee flexor, ankle plantar flexor, and ankle dorsiflexor strength testing within 7 days after STS testing. Regression analyses were performed using the average weight-adjusted isokinetic hip, knee, and ankle joint strength scores as the independent variables and both STS test scores as the dependent variables. Results. Regression analyses including all 6 leg strength variables explained 48% (p =.0001) and 35% (p =.007) of the variance in 5-chair STS test scores and 30-second chair STS scores, respectively. Ankle plantar flexor, hip flexor, and knee extensor strength were the strongest predictors for both STS tests. Conclusions. Although ankle plantar flexor, hip flexor, and knee extensor strength play essential roles in performing the STS movement, most STS variance was unexplained, suggesting that important additional variables are also involved in completing the movement.
In the past two decades, pions created in the high density regions of heavy ion collisions have been predicted to be sensitive at high densities to the symmetry energy term in the nuclear equation of ...state, a property that is key to our understanding of neutron stars. In a new experiment designed to study the symmetry energy, the multiplicities of negatively and positively charged pions have been measured with high accuracy for central 132Sn+124Sn, 112Sn+124Sn, and 108Sn+112Sn collisions at E/A=270 MeV with the SπRIT Time Projection Chamber. While individual pion multiplicities are measured to 4% accuracy, those of the charged pion multiplicity ratios are measured to 2% accuracy. We compare these data to predictions from seven major transport models. The calculations reproduce qualitatively the dependence of the multiplicities and their ratios on the total neutron and proton number in the colliding systems. However, the predictions of the transport models from different codes differ too much to allow extraction of reliable constraints on the symmetry energy from the data. This finding may explain previous contradictory conclusions on symmetry energy constraints obtained from pion data in Au+Au system. These new results call for still better understanding of the differences among transport codes, and new observables that are more sensitive to the density dependence of the symmetry energy.
This work provides the consequence of aging on the conduction mechanism of fresh as well as aged Se and As
2
Se
3
chalcogenide glasses (ChGs). In this analysis, the sample synthesized by the ...melt-quench route was used as identical disk-shaped pellets for current–voltage (
I
–
V
) characteristics at different temperatures. Our observation shows the absence of space charge limited conduction (SCLC) for both fresh as well as aged samples of Se and As
2
Se
3.
The Poole–Frenkel conduction mechanism is detected as the leading model for fresh and aged samples of both Se and As
2
Se
3
glasses. The activation energy is found to rise appreciably due to the aging effect of Se while almost constant for As
2
Se
3
samples. The reason behind this may be the slight growth of crystallite due to aging in Se glass.
Highlights • Cognitive motor interference (CMI) is increased in the earliest stages of MS. • Central executive plays a major role in CMI and step initiation. • Reduced divided attention capacity may ...be the cause of increased CMI in MS.
The majority of the sludge from the treatment of wastewater in milk processing plants is land spread. The drawbacks of land spreading include local oversupply due to high transport costs, which ...results in sludge being spread on lands in the vicinity of the dairy factories. Local oversupply can lead to accumulation of certain substances in soil through annual application over many years. Therefore, in the long term, there is a need for alternative methods to recover energy and nutrients from increasing volumes of sludge generated from dairy processing. Pyrolysis offers a potential alternative to land spreading, which can reduce health and environmental risks, while providing an avenue for the recovery of energy and nutrients. Pyrolysis allows energy recovery in the form of a high calorific value pyrolysis gas and a char which may be used as a soil amendment. In this study pyrolysis of dried dairy sludge was carried out at pilot scale. The results indicate that a dried biological sludge can be successfully pyrolysed and when mixed with wood the resulting char meets European Biochar Certificate criteria regarding carbon content. Most of the initial energy content of the feedstock was retained in the pyrolysis gas prior to cleaning, 53%, compared to 34.5% in the char and 1.5% in the tar. For the pyrolysis gas after cleaning (mainly cracking in presence of air) the initial energy content of the feedstock retained in the gas was only slightly higher than that retained in the char, 39.2% versus 34.5%, while the tar accounted for 0.8% of the initial energy content.
We have experimentally determined a phase diagram for cylinder-forming polystyrene-block-polybutadien-block-polystyrene triblock copolymer in thin films. The phase behavior can be modeled in great ...detail by dynamic density functional theory. Deviations from the bulk structure, such as wetting layer, perforated lamella, and lamella, are identified as surface reconstructions. Their stability regions are determined by an interplay between surface fields and confinement effects.
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