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Background: Despite a higher prevalence of traumatic spinal cord injury (TSCI) amongst Canadian Indigenous peoples, there is a paucity of studies focused on Indigenous TSCI. We present the first Canada-wide study comparing TSCI amongst Canadian Indigenous and non-Indigenous peoples. Methods: This study is a retrospective analysis of prospectively-collected TSCI data from the Rick Hansen Spinal Cord Injury Registry (RHSCIR) from 2004-2019. We divided participants into Indigenous and non-Indigenous cohorts and compared them with respect to demographics, injury mechanism, level, severity, and outcomes. Results: Compared with non-Indigenous patients, Indigenous patients were younger, more female, less likely to have higher education, and less likely to be employed. The mechanism of injury was more likely due to assault or transportation-related trauma in the Indigenous group. The length of stay for Indigenous patients was longer. Indigenous patients were more likely to be discharged to a rural setting, less likely to be discharged home, and more likely to be unemployed following injury. Conclusions: Our results suggest that more resources need to be dedicated for transitioning Indigenous patients sustaining a TSCI to community living and for supporting these patients in their home communities. A focus on resources and infrastructure for Indigenous patients by engagement with Indigenous communities is needed.
We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum targets. The results illustrate the coexistence of ring-like and filamentation structures. We implement the knife edge method into the radiochromic film detector to map the accelerated beams, measuring a source size of 30–110 μm for protons of more than 5 MeV. The diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons, exhibiting non-laminar features. Particle-in-cell simulations reproduced the experimental results, showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam profile. Our work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.
Psychotic-like experiences (PLEs) are risk factors for the development of psychiatric conditions like schizophrenia, particularly if associated with distress. As PLEs have been related to alterations in both white matter and cognition, we investigated whether cognition (g-factor and processing speed) mediates the relationship between white matter and PLEs.
We investigated two independent samples (6170 and 19 891) from the UK Biobank, through path analysis. For both samples, measures of whole-brain fractional anisotropy (gFA) and mean diffusivity (gMD), as indications of white matter microstructure, were derived from probabilistic tractography. For the smaller sample, variables whole-brain white matter network efficiency and microstructure were also derived from structural connectome data.
The mediation of cognition on the relationships between white matter properties and PLEs was non-significant. However, lower gFA was associated with having PLEs in combination with distress in the full available sample (standardized β = −0.053, p = 0.011). Additionally, lower gFA/higher gMD was associated with lower g-factor (standardized β = 0.049, p < 0.001; standardized β = −0.027, p = 0.003), and partially mediated by processing speed with a proportion mediated of 7% (p = < 0.001) for gFA and 11% (p < 0.001) for gMD.
We show that lower global white matter microstructure is associated with having PLEs in combination with distress, which suggests a direction of future research that could help clarify how and why individuals progress from subclinical to clinical psychotic symptoms. Furthermore, we replicated that processing speed mediates the relationship between white matter microstructure and g-factor.
A disruption database characterizing the current quench of disruptions with ITER-like tungsten divertor has been developed on EAST. It provides a large number of plasma parameters describing the predisruptive plasma, current quench time, eddy current, and mitigation by massive impurity injection, which shows that the current quench time strongly depends on magnetic energy and post-disruption electron temperature. Further, the energy balance and magnetic energy dissipation during the current quench phase has been well analysed. Magnetic energy is also demonstrated to be dissipated mainly by ohmic reheating and inductive coupling, and both of the two channels have great effects on current quench time. Also, massive gas injection is an efficient method to speed up the current quench and increase the fraction of impurity radiation.
Klebsiella pneumoniae is a common pathogen associated with nosocomial infections and is characterised serologically by capsular polysaccharide (K) and lipopolysaccharide O antigens. We surveyed a total of 348 non-duplicate K. pneumoniae clinical isolates collected over a 1-year period in a tertiary care hospital, and determined their O and K serotypes by sequencing of the wbb Y and wzi gene loci, respectively. Isolates were also screened for antimicrobial resistance and hypervirulent phenotypes; 94 (27.0%) were identified as carbapenem-resistant (CRKP) and 110 (31.6%) as hypervirulent (hvKP). isolates fell into 58 K, and six O types, with 92.0% and 94.2% typeability, respectively. The predominant K types were K14K64 (16.38%), K1 (14.66%), K2 (8.05%) and K57 (5.46%), while O1 (46%), O2a (27.9%) and O3 (11.8%) were the most common. CRKP and hvKP strains had different serotype distributions with O2a:K14K64 (41.0%) being the most frequent among CRKP, and O1:K1 (26.4%) and O1:K2 (17.3%) among hvKP strains. Serotyping by gene sequencing proved to be a useful tool to inform the clinical epidemiology of K. pneumoniae infections and provides valuable data relevant to vaccine design.
Flexibility is one of the important mechanical performance parameters of stent. The flexibility of tapered stents, especially self-expanding tapered stents, remains unknown. In this study, we developed a new selfexpanding tapered stent for tapered arteries and performed a numerical investigation of stent flexibility by using finite element method. The effect of stent design parameters, including taper and link space width, on stent flexibility was studied. The flexibility of the proposed stent was also compared with that of traditional cylindrical stents. Results show that the tapered stent is more flexible than the traditional cylindrical stent. Furthermore, the flexibility of the tapered stent increases with increasing stent taper and stent link space width. The increase in the stent link space width can contribute to the reduction in the peak stress. Therefore, tapered stents with high link space width will improve the stent flexibility. This work provides useful information for improvement of stent design and clinical selection.
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3′-untranslated region of the CLDN5 locus was associated with schizophrenia (χ2 = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5′-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (χ2) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (χ2 = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.
An increasing number of studies have described the relationship between velo-cardio-facial syndrome (VCFS) and schizophrenia. in a family-based study, we found that rs10314, a single nucleotide polymorphism (SNP) present in the 3’-flanking region of the CLDN5 gene, was associated with schizophrenia among a Chinese population. High false positive rate is a common problem with the association study of human diseases. It is very important to replicate an initial finding with different samples and experimental designs.
A total of 749 patients with schizophrenia and 383 age and sex matched healthy control subjects in Chinese population were recruited. PCR-based RFLP protocol was applied to genotype rs10314 to see its disease association.
The χ2 goodness-of-fit test showed that the genotypic distributions of rs10314 were in Hardy-Weinberg equilibrium in both the patient group (χ2=1.12, P=0.289) and the control group (χ2=0.22, P=0.639). rs10314 was associated with schizophrenia with an odds ratio (OR) of 1.32 in the male subjects (χ2=5.45, P=0.02, 95% CI 1.05-1.67) but not in the female subjects (χ2=0.64, P=0.425, OR=1.14, 95% CI 0.83-1.57). the χ2 test showed a genotypic association only for combined samples (χ2=7.80, df=2, P=0.02). SNP rs10314 is a G to C base change. Frequency of the genotypes containing the C allele was significantly higher in the patient group than in the control group.
The present work shows that the CLDN5 gene polymorphism is more likely to be involved in schizophrenic men than women, suggesting that this gene may contribute to the gender differences in schizophrenia.
The pharmacological properties of betel nut which is consumed in immense quantities in the East as a cognitive enhancer. There was no evidence to prove the cognitive enhancement effect of chewing bet nut.
We tried to demonstrated that chewing betel nut enhanced cognitive performance, mainly attention, especially when they felt fatigue.
First, we demonstrated the fatigue effect induced by repeated continuous performance attention tests. Second, we tested the cognitive enhancement effect induced by betel nut.
Experiment 1, thirty-four volunteers, naive to betel nut, performed a continuous performance test three times without chewing anything before-and-during the test. Experiment 2, seventeen subjects who are used to chew betel nut performed the same tests. During the second and third session, they were given two pieces of gums or five piece of betel nut to chew. The sequence of chewing were counterbalanced.
In experiment 1, omission error rate was significantly different between section 1 and 3. Commission error was significantly different between section 1 and 2, 3 (Figure 1). In experiment 2, omission error rate was significantly different between baseline and section of chewing betel nut (Figure 2). Commission error rate had no difference between three sections. In both experiments, reaction time of different sections had no difference.
[Figue 1. The error rate of different types errors.]
Chewing betel nut could reverse the increase of omission error rate but chewing gum could not improve it. Either chewing betel nut or gum improved commission error rate. This study demonstrate the cognitive enhancement effect of chewing betel nut.
Several questions still exist in the literature on the relationship between cumulative exposure to work-related incidents and posttraumatic stress disorder (PTSD) in First Responders (FR).
To address three unanswered questions in the field.
(1) Are different cumulative exposure scoring algorithms similarly related to PTSD?
(2) Is PTSD associated only with incidents rated as severe and traumatic?
(3) Can we identify cut-off scores of cumulative exposure that maximize sensitivity and specificity to predict PTSD?
To better characterize the relationship between cumulative exposure and PTSD in FR.
The association between exposure and PTSD was examined with logistic and linear regression and with receiver operating characteristic analysis in 349 FR.
(1) The strength of the association between PTSD and total cumulative exposure indexes varied across different scoring algorithms.
(2) Compared to total cumulative exposure indexes and to sub-scores of exposure to non-traumatic and/or less severe incidents, sub-scores indexing exposure to severe traumatic events only were more strongly and significantly associated with PTSD.
(3) The use of two cut-off scores maximizes sensitivity and specificity to predict PTSD.
(1) The relationship between current PTSD and cumulative exposure is partially dependent on the approach used to quantify exposure.
(2) Focusing on the assessment of cumulative exposure to severe traumatic events is sufficient to predict PTSD, and might be more useful and effective in research and clinical decision-making.
(3) Sensitivity and specificity of exposure scores might help improve secondary prevention (early detection and effective intervention) of individuals at risk.
Item Response Theory (IRT) allows for dimensional scaling of the severity of a disorder, and comparison of symptoms’ properties across different measures of the same trait and across groups. IRT has never been applied to Posttraumatic Stress Disorder (PTSD).
To determine discrimination and severity parameters of PTSD symptoms measured with two instruments, and to examine gender- and age-related Differential Item Functioning (DIF) of PTSD indicators.
To inform the dimensional scaling of PTSD in youth.
IRT was applied to PTSD items measured with the DPS and the PTSD-RI in 6,733 9/11-exposed youths. DIF analysis was performed in the sample stratified by gender and age (8-13; 14-21).
DPS and PTSD-RI items are most informative at intermediate and severe levels of PTSD, respectively. Across instruments, discrimination was greatest for insomnia and nightmares, and lowest for 9/11-related thoughts. Severity parameters were highest for avoidance and numbing symptoms, and lowest for 9/11-related thoughts. The majority of PTSD symptoms showed significant DIF across subgroups.
DPS and PTSD-RI criteria are informative at different levels of PTSD severity. PTSD symptoms differentially discriminate among individuals along the PTSD continuum, and are most informative at different levels of PTSD severity. These results could inform dimensional scaling of PTSD, and allow for flexibility in assigning cut-off points for facilitating clinical decision-making. PTSD criteria do not provide the same information across subgroups defined by gender and age, suggesting that symptoms differ in the way they represent severe post-traumatic stress reactions across groups.
The effects of bed roughness, isolated from those of bed permeability, on the vertical transport processes across the sediment–water interface (SWI) are not well understood. We compare the statistics and structure of the mean flow and turbulence in open-channel flows with a friction Reynolds number of 395 and a permeability Reynolds number of 2.6 over sediments with either regular or random grain packing at the SWI. The regular sediment interface is formed by cubic packing of spheres aligned with the mean-velocity direction. It is shown that, even in the absence of any bedform, the subtle details of the particle roughness alone can significantly affect the dynamics of turbulence and the time-mean flow. Such effects translate to large differences in penetration depths, apparent permeabilities, vertical mass fluxes and subsurface flow paths of passive scalars. The less organized distribution of mean recirculation regions near the interface with a random packing leads to a more isotropic form-induced stress tensor. The augmented wall-normal form-induced fluctuations play a significant role in increasing mixing and wall-normal mass and momentum exchange.
The binary metal oxides are increasingly used as supercapacitor electrode materials in energy storing devices. Particularly NiCo2O4 has shown promising electrocapacitive performance with high specific capacitance and energy density. The electrocapacitive performance of these oxides largely depends on their morphology and electrical properties governed by their energy band-gaps and defects. The morphological structure of NiCo2O4 can be altered via the synthesis route, while the energy band-gap could be altered by doping. Also, doping can enhance crystal stability and bring in grain refinement, which can further improve the much-needed surface area for high specific capacitance. Given the above, this study evaluates the electrochemical performance of Ca-doped Ni1-xCaxCo2O4 (0 ≤ x ≤ 0.8) compounds. This stipulates promising applications for electrodes in future supercapacitors.