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Bentonites are readily available clays used in the livestock industry as feed additives to reduce aflatoxin (AF) exposure; their potential interaction with nutrients is the main concern limiting their use, however. The objective of the present study was to determine the safety of a dietary sodium-bentonite (Na-bentonite) supplement as a potential AF adsorbent, using juvenile Sprague Dawley (SD) rats as a research model. Animals were fed either a control diet or a diet containing Na-bentonite at 0.25% and 2% (w/w) inclusion rate. Growth, serum, and blood biochemical parameters, including selected serum vitamins (A and E) and elements such as calcium (Ca), potassium (K), iron (Fe), and zinc (Zn) were measured. The mineral characteristics and the aflatoxin B1 sorption capacity of Na-bentonite were also determined. By the end of the study, males gained more weight than females in control and Na-bentonite groups (p ≤ 0.0001); the interaction between treatment and sex was not significant (p = 0.6780), however. Some significant differences between the control group and bentonite treatments were observed in serum biochemistry and vitamin and minerals measurements; however, parameters fell within reference clinical values reported for SD rats and no evidence of dose-dependency was found. Serum Na and Na/K ratios were increased, while K levels were decreased in males and females from Na-bentonite groups. Serum Zn levels were decreased only in males from Na-bentonite treatments. Overall, results showed that inclusion of Na-bentonite at 0.25% and 2% did not cause any observable toxicity in a 3-month rodent study.
Previous findings suggest that time setting errors (TSEs) in the Clock Drawing Test (CDT) may be related mainly to impairments in semantic and executive function. Recent attempts to dissociate the classic stimulus-bound error (setting the time to “10 to 11” instead of “10 past 11”) from other TSEs, did not support hypotheses regarding this error being primarily executive in nature or different from other time setting errors in terms of neurocognitive correlates. This study aimed to further investigate the cognitive correlates of stimulus-bound errors and other TSEs, in order to trace possible underlying cognitive deficits.
Methods:
We examined cognitive test performance of participants with preliminary diagnoses associated with mild cognitive impairment. Among 490 participants, we identified clocks with stimulus-bound errors (n = 78), other TSEs (n = 41), other errors not related to time settings (n = 176), or errorless clocks (n = 195).
Results:
No differences were found on any dependent measure between the stimulus-bound and the other TSErs groups. Group comparisons suggested TSEs in general, to be associated with lower performance on various cognitive measures, especially on semantic and working memory measures. Regression analysis further highlighted semantic and verbal working memory difficulties as being the most prominent deficits associated with these errors.
Conclusion:
TSEs in the CDT may indicate underlying deficits in semantic function and working memory. In addition, results support previous findings related to the diagnostic value of TSEs in detecting cognitive impairment.
In this brief communication, we discuss the current landscape and unmet needs of pediatric to adult transition care in neurology. Optimizing transition care is a priority for patients, families, and providers with growing discussion in neurology. We also introduce the activities of the University of Toronto Pediatric-Adult Transition Working Group – a collaborative interdivisional and inter-subspeciality group of faculty, advanced-practice providers, trainees, and patient-family advisors pursuing collaboration with patients, families, and universities from across Canada. We envision that these efforts will result in a national neurology transition strategy that will inform designation of health authority attention and funding.
We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast Laser Facility (SULF). The peak power reaches 2.4 PW on target without the last amplifying during the experiment. The laser energy of 72 ± 9 J is directed to a focal spot of approximately 6 μm diameter (full width at half maximum) in 30 fs pulse duration, yielding a focused peak intensity around 2.0 × 1021 W/cm2. The first laser-proton acceleration experiment is performed using plain copper and plastic targets. High-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4 μm via target normal sheath acceleration. For plastic targets of tens of nanometers thick, the proton cut-off energy is approximately 20 MeV, showing ring-like or filamented density distributions. These experimental results reflect the capabilities of the SULF-10 PW beamline, for example, both ultrahigh intensity and relatively good beam contrast. Further optimization for these key parameters is underway, where peak laser intensities of 1022–1023 W/cm2 are anticipated to support various experiments on extreme field physics.
This article examines the origins and dynamics of an extraordinary wave of protests in Hong Kong in 2019–2020. Despite lacking visible political opportunities and organizational resources, the protest movement drew resilient, mass participation unparalleled in the city's history and much of the world. Drawing from original on-site surveys and online datasets, we conceptualize the Anti-Extradition Law Amendment Bill Movement as a form of “total mobilization from below.” The totality of the mobilization depended on a set of interactive mechanisms: abeyant civil society networks concealed after the 2014 Umbrella Movement were activated by threats over extradition and institutional decay, whereas affective ties developed through conflicts and mutual assistance were amplified by digital communication. The movement's characteristics in terms of protest scale, mobilizing structure, use of alternative spaces, and group solidarity are examined. The spasmodic moments of mobilization are explained by a nexus of network building that took place in an unreceptive environment and at a critical juncture. The roles of threats and emotions in mass mobilizations are also analysed.
Background: Treatment decisions for patients with autoimmune encephalitis (AE) frequently need to be made before results from autoantibody testing are available, as early treatment is associated with better outcomes. Cerebrospinal fluids (CSF) white blood cell (WBC) count and protein concentration measured early on in the disease process is often used, in combination with other clinical factors, to evaluate the likelihood that a patient has AE. Methods: CSF characteristics (WBC count, protein concentration, and oligoclonal banding) measured in a first AE presentation, prior to results of autoantibodies being available, were retrospectively analyzed at two tertiary care centers. Results: Ninety-five patients were included in the study. CSF WBC counts and protein levels were within normal limits for 27% (CI95%: 19–37) of patients with AE. When results of oligoclonal banding were added, 14% (CI95%: 6–16) of patients had “normal” CSF. The median CSF white blood cell count was 8 cells/mm3 (range: 0–544) and the median CSF protein concentration was 0.42 g/L (range: 0.15–3.92). Conclusions: A substantial proportion of patients with early active AE had a CSF WBC count or protein concentration within the normal. Inclusion of CSF oligoclonal banding may help identify a higher proportion of patients with an inflammatory CSF profile early in the disease process.
In this era of spatially resolved observations of planet-forming disks with Atacama Large Millimeter Array (ALMA) and large ground-based telescopes such as the Very Large Telescope (VLT), Keck, and Subaru, we still lack statistically relevant information on the quantity and composition of the material that is building the planets, such as the total disk gas mass, the ice content of dust, and the state of water in planetesimals. SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is an infrared space mission concept developed jointly by Japan Aerospace Exploration Agency (JAXA) and European Space Agency (ESA) to address these questions. The key unique capabilities of SPICA that enable this research are (1) the wide spectral coverage $10{-}220\,\mu\mathrm{m}$, (2) the high line detection sensitivity of $(1{-}2) \times 10^{-19}\,\mathrm{W\,m}^{-2}$ with $R \sim 2\,000{-}5\,000$ in the far-IR (SAFARI), and $10^{-20}\,\mathrm{W\,m}^{-2}$ with $R \sim 29\,000$ in the mid-IR (SPICA Mid-infrared Instrument (SMI), spectrally resolving line profiles), (3) the high far-IR continuum sensitivity of 0.45 mJy (SAFARI), and (4) the observing efficiency for point source surveys. This paper details how mid- to far-IR infrared spectra will be unique in measuring the gas masses and water/ice content of disks and how these quantities evolve during the planet-forming period. These observations will clarify the crucial transition when disks exhaust their primordial gas and further planet formation requires secondary gas produced from planetesimals. The high spectral resolution mid-IR is also unique for determining the location of the snowline dividing the rocky and icy mass reservoirs within the disk and how the divide evolves during the build-up of planetary systems. Infrared spectroscopy (mid- to far-IR) of key solid-state bands is crucial for assessing whether extensive radial mixing, which is part of our Solar System history, is a general process occurring in most planetary systems and whether extrasolar planetesimals are similar to our Solar System comets/asteroids. We demonstrate that the SPICA mission concept would allow us to achieve the above ambitious science goals through large surveys of several hundred disks within $\sim\!2.5$ months of observing time.
In rapidly urbanising China, a high number of elderly people, the so-called ‘laopiao’, float to cities where their sons or daughters live to look after their children and grandchildren. Laopiao in urban China are thought to suffer poor mental health owing to their floating status. This study explores the inter-relationship among social capital, the built environment and mental health in urban China. Using a recent survey conducted in Nanjing (N = 591), structural equation modelling was performed to compare the local elderly people and the laopiao. Results showed that mental health determinants are dissimilar between the two groups of elderly people. Bonding social capital promotes mental health in both groups, while bridging and linking social capital only contributes to the mental health of the laopiao. Also, access to public transportation is positively correlated with mental health in both groups. Furthermore, lower street network density and better access to parks enhance the mental health of the local elderly people, while higher street network density and more open space within a community enhance the mental health of the laopiao. Our findings suggest that different policy measures should be implemented for different groups of elderly people in urban China to improve their mental health.
To investigate the effect of Chinese herb Danshen-Dahuang on learning and memory ability in rats with Alzheimer disease (AD) induced by D-galactose and AlCl3 and its possible mechanisms.
Methods:
The AD model was produced by injecting D-galactose and AlCl3 intraperitoneally for 90 days. Since the 20th day of D-galactose and AlCl3 intraperitoneal injection, the rats in Danshen-Dahuang group had been treated with Danshen-Dahuang extraction by intragastric administration for 70 days. Subsequently,learning and memory ability of the mice was evaluated by Morris water maze and hippocampal gene expression of APP, PS1 was tested by reverse transcription polymerase chain reaction (RT-PCR).
Results:
Rats intragastric administration with Danshen-Dahuang, mice had shorter latency (P< 0.05) and less error times (P< 0.05) in water maze test compared with those in AD model group. At the same time, Danshen-Dahuang down regulated the expression of APP, PS1 mRNA (P< 0.05) in hippocampus.
Conclusions:
Danshen-Dahuang improves the learning and memory ability of AD rats, its mechanism may be related to the downregulated expression of APP, PS1 mRNA.
Many schizophrenia patients experience residual symptoms even after treatment. Electroconvulsive therapy (ECT) is often used in medication-resistant schizophrenia patients when pharmacologic interventions have failed; however, the mechanism of action is unclear. Brain-derived neurotrophic factor (BDNF) levels are reduced in drug-naive, first-episode schizophrenia and are increased by antipsychotic treatment. We tested the hypothesis that ECT increases serum BDNF levels by measuring BDNF concentrations in schizophrenia patients before and after they received ECT.
Methods
A total of 160 patients with schizophrenia were examined. The ECT group (n = 80) was treated with antipsychotics and ECT (eight to 10 sessions administered every other day). The drug therapy group (n = 80) received only antipsychotic treatment. A control group (n = 77) was recruited that served as the baseline for comparison.
Results
Baseline serum BDNF level in ECT group was lower than in controls (9.7 ± 2.1 vs. 12.4 ± 3.2 ng/ml; P < 0.001), but increased after ECT, such that there was no difference between the two groups (11.9 ± 3.3 vs. 12.4 ± 3.2 ng/ml; P = 0.362). There was no correlation between patients’ Positive and Negative Syndrome Scale (PANSS) score and serum BDNF level before ECT; however, a negative correlation was observed after ECT (total: r = −0.692; P < 0.01). From baseline to remission after ECT, serum BDNF level increased (P < 0.001) and their PANSS score decreased (P < 0.001). Changes in BDNF level (2.21 ± 4.10 ng/ml) and PANSS score (28.69 ± 14.96) were positively correlated in the ECT group (r = 0.630; P < 0.01).
Conclusions
BDNF level was lower in schizophrenia patients relative to healthy controls before ECT and medication. BDNF level increased after ECT and medication, and its longitudinal change was associated with changes in patients’ psychotic symptoms. These results indicate that BDNF mediates the antipsychotic effects of ECT.
There is lack of Cameroonian adult neuropsychological (NP) norms, limited knowledge concerning HIV-associated neurocognitive disorders in Sub-Saharan Africa, and evidence of differential inflammation and disease progression based on viral subtypes. In this study, we developed demographically corrected norms and assessed HIV and viral genotypes effects on attention/working memory (WM), learning, and memory.
Method:
We administered two tests of attention/WM [Paced Auditory Serial Addition Test (PASAT)-50, Wechsler Memory Scale (WMS)-III Spatial Span] and two tests of learning and memory [Brief Visuospatial Memory Test-Revised (BVMT-R), Hopkins Verbal Learning Test-Revised (HVLT-R)] to 347 HIV+ and 395 seronegative adult Cameroonians. We assessed the effects of viral factors on neurocognitive performance.
Results:
Compared to controls, people living with HIV (PLWH) had significantly lower T-scores on PASAT-50 and attention/WM summary scores, on HVLT-R total learning and learning summary scores, on HVLT-R delayed recall, BVMT-R delayed recall and memory summary scores. More PLWH had impairment in attention/WM, learning, and memory. Antiretroviral therapy (ART) and current immune status had no effect on T-scores. Compared to untreated cases with detectable viremia, untreated cases with undetectable viremia had significantly lower (worse) T-scores on BVMT-R total learning, BVMT-R delayed recall, and memory composite scores. Compared to PLWH infected with other subtypes (41.83%), those infected with HIV-1 CRF02_AG (58.17%) had higher (better) attention/WM T-scores.
Conclusions:
PLWH in Cameroon have impaired attention/WM, learning, and memory and those infected with CRF02_AG viruses showed reduced deficits in attention/WM. The first adult normative standards for assessing attention/WM, learning, and memory described, with equations for computing demographically adjusted T-scores, will facilitate future studies of diseases affecting cognitive function in Cameroonians.
NASA's Operation IceBridge mission flew over the Ross Sea, Antarctica (20 and 27 November 2013) and collected data with Airborne Topographic Mapper (ATM) and Digital Mapping System (DMS). Using the DMS and reflectivity of ATM L1B, leads are detected to define local sea level height. The total freeboard is then obtained and converted to ice thickness. The estimated mean sea-ice thickness values are found to be in the 0.48–0.99 m range. Along the N-S track, sea ice was thinner southward rather than northward of the fluxgate, resulting in two peaks of modal thickness: 0.35 m (south) and 0.7 m (north). This supports that new ice produced in coastal polynyas is transported northward by katabatic winds off the ice-shelf. The lowest (2%) elevation method used for freeboard retrieval for ICESat is also tested for ATM data. It is found that the lowest elevation method tends to overestimate freeboard, but mean values are less affected than mode values. Using mean thickness values of ICESat and ATM along the ‘fluxgate’, separating the shelf from the deep ocean, the exported ice volume at this ‘fluxgate’ is found to be higher during the ICESat years (2003–2008) than during the IceBridge year (2013).
Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Methods:
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Results:
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
Conclusion:
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
Plant nitrogen (N) links with many physiological progresses of crop growth and yield formation. Accurate simulation is key to predict crop growth and yield correctly. The aim of the current study was to improve the estimation of N uptake and translocation processes in the whole rice plant as well as within plant organs in the RiceGrow model by using plant and organ maximum, critical and minimum N dilution curves. The maximum and critical N (Nc) demand (obtained from the maximum and critical curves) of shoot and root and Nc demand of organs (leaf, stem and panicle) are calculated by N concentration and biomass. Nitrogen distribution among organs is computed differently pre- and post-anthesis. Pre-anthesis distribution is determined by maximum N demand with no priority among organs. In post-anthesis distribution, panicle demands are met first and then the remaining N is allocated to other organs without priority. The amount of plant N uptake depends on plant N demand and N supplied by the soil. Calibration and validation of the established model were performed on field experiments conducted in China and the Philippines with varied N rates and N split applications; results showed that this improved model can simulate the processes of N uptake and translocation well.
Background: A need exists to characterise the long-term cognitive outcomes in patients who recovered from autoimmune encephalitis and to identify the modifiable factors associated with improved outcomes. Methods: We retrospectively analysed data from patients diagnosed with autoimmune encephalitis in our outpatient autoimmune encephalitis clinic over a 5-year period, where the Montreal Cognitive Assessment (MoCA) is routinely administered. Results: In total, 21 patients met the inclusion criteria, of whom 52% had persistent cognitive impairment at their latest follow-up (median delay to testing=20 months, range 13-182). Visuospatial and executive abilities, language, attention, and delayed recall were predominantly affected. Patients with status epilepticus at presentation had lower total MoCA scores at their last follow-up (median total score 21, range 15-29) compared with patients without status epilepticus at presentation (median total score 27.5, range 21-30; r2=0.366, p=0.004). Patients who experienced delays of more than 60 days from symptom onset to initiation of treatment (either immunosuppression or tumour removal) were more likely to have a MoCA score compatible with cognitive impairment at their last follow-up (r2=0.253, p=0.0239; z-score=−2.01, p=0.044). Conclusions: Our study suggests that the MoCA may be used to evaluate cognition in recovering patients with autoimmune encephalitis. Delays to treatment shorter than 60 days and absence of status epilepticus at onset were associated with better performance on the MoCA obtained more than 1 year after symptom onset, and may predict better long-term cognitive outcomes.