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In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee, along with a multidisciplinary group of experts and Canadian Epilepsy Alliance representatives, has developed a position statement about the use of medical cannabis for epilepsy. This article addresses the current Canadian legal framework, recent publications about its efficacy and safety profile, and our understanding of the clinical issues that should be considered when contemplating cannabis use for medical purposes.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Oxidative stress is implicated in the aetiology of schizophrenia, and the antioxidant defence system (AODS) may be protective in this illness. We examined the major antioxidant glutathione (GSH) in prefrontal brain and its correlates with clinical and demographic variables in schizophrenia.
GSH levels were measured in the dorsolateral prefrontal region of 28 patients with chronic schizophrenia using a magnetic resonance spectroscopy sequence specifically adapted for GSH. We examined correlations of GSH levels with age, age at onset of illness, duration of illness, and clinical symptoms.
We found a negative correlation between GSH levels and age at onset (r = −0.46, p = 0.015), and a trend-level positive relationship between GSH and duration of illness (r = 0.34, p = 0.076).
Our findings are consistent with a possible compensatory upregulation of the AODS with longer duration of illness and suggest that the AODS may play a role in schizophrenia.
We present the first general metric for attractor overlap (MAO) facilitating an unsupervised comparison of flow data sets. The starting point is two or more attractors, i.e. ensembles of states representing different operating conditions. The proposed metric generalizes the standard Hilbert-space distance between two snapshot-to-snapshot ensembles of two attractors. A reduced-order analysis for big data and many attractors is enabled by coarse graining the snapshots into representative clusters with corresponding centroids and population probabilities. For a large number of attractors, MAO is augmented by proximity maps for the snapshots, the centroids and the attractors, giving scientifically interpretable visual access to the closeness of the states. The coherent structures belonging to the overlap and disjoint states between these attractors are distilled by a few representative centroids. We employ MAO for two quite different actuated flow configurations: a two-dimensional wake with vortices in a narrow frequency range and three-dimensional wall turbulence with a broadband spectrum. In the first application, seven control laws are applied to the fluidic pinball, i.e. the two-dimensional flow around three circular cylinders whose centres form an equilateral triangle pointing in the upstream direction. These seven operating conditions comprise unforced shedding, boat tailing, base bleed, high- and low-frequency forcing as well as two opposing Magnus effects. In the second example, MAO is applied to three-dimensional simulation data from an open-loop drag reduction study of a turbulent boundary layer. The actuation mechanisms of 38 spanwise travelling transversal surface waves are investigated. MAO compares and classifies these actuated flows in agreement with physical intuition. For instance, the first feature coordinate of the attractor proximity map correlates with drag for the fluidic pinball and for the turbulent boundary layer. MAO has a large spectrum of potential applications ranging from a quantitative comparison between numerical simulations and experimental particle-image velocimetry data to the analysis of simulations representing a myriad of different operating conditions.
Immune system markers may predict affective disorder treatment response, but whether an overall immune system marker predicts bipolar disorder treatment effect is unclear.
Bipolar CHOICE (N = 482) and LiTMUS (N = 283) were similar comparative effectiveness trials treating patients with bipolar disorder for 24 weeks with four different treatment arms (standard-dose lithium, quetiapine, moderate-dose lithium plus optimised personalised treatment (OPT) and OPT without lithium). We performed secondary mixed effects linear regression analyses adjusted for age, gender, smoking and body mass index to investigate relationships between pre-treatment white blood cell (WBC) levels and clinical global impression scale (CGI) response.
Compared to participants with WBC counts of 4.5–10 × 109/l, participants with WBC < 4.5 or WBC ≥ 10 showed similar improvement within each specific treatment arm and in gender-stratified analyses.
An overall immune system marker did not predict differential treatment response to four different treatment approaches for bipolar disorder all lasting 24 weeks.
Introduction: Renal colic is one of the most common presentations to the emergency department (ED), and often requires complex interdisciplinary collaboration between emergency physicians and urology surgeons. Previous literature has shown that adoption of interdisciplinary rapid referral clinics can improve both timeliness of care and patient outcomes. However, these Acute Care Surgery models have not yet been commonly adopted for urology care in the ED. Methods: In July 2016, we adopted the intervention of an Acute Care Urology (ACU) model through the creation of a rapid referral clinic dedicated to ED patient referrals, the addition of an ACU surgeon, and enhanced use of daytime OR blocks. We conducted a manual chart review of 579 patients presenting to the ED with a complaint of renal colic. Patient data was collected in two separate time periods to analyze trends before implementation of the ACU model (pre-intervention, September - November 2015), to examine the model's impact (post-intervention, September - November 2016). Secondary methods of evaluation included a survey of 20 ED physicians to capture subjective feedback through Likert scale data. Results: Of the evaluated 579 patients with a complaint of renal colic,194 patients were discharged from ED with an diagnosis of obstructing kidney stone and were referred to urology for outpatient care. The ED-to-clinic time was significantly lower for those in the ACU model (p <0.001). The mean time to clinic was 15.76 days (SD = 15.47, range 1-93) pre-intervention versus 4.17 days (SD = 2.33, range = 1-12) post-intervention. Furthermore, the ACU clinic allowed significantly more patients to be referred for outpatient care (p = 0.0004). There was also higher likelihood that patients would successfully obtain an appointment following referral (p = 0.0055). Decreasing trends were shown in mean ED wait time, in addition to time from assessment to procedure. Results of the qualitative survey were overwhelmingly positive. All 20 surveyed ED physicians were more confident that outpatients would be seen in a timely manner (85% strongly agree, 15% agree). Qualitative feedback included the belief that follow-up is more accessible, that ED physicians are less likely to page the on-call urologist, and that they are able to discharge patients sooner. Conclusion: The ACU model for patients with renal colic may be beneficial in reducing ED-to-clinic time, ensuring proper follow-up after ED diagnosis, and improving patient care within the ED.
Laser–solid interactions are highly suited as a potential source of high energy X-rays for nondestructive imaging. A bright, energetic X-ray pulse can be driven from a small source, making it ideal for high resolution X-ray radiography. By limiting the lateral dimensions of the target we are able to confine the region over which X-rays are produced, enabling imaging with enhanced resolution and contrast. Using constrained targets we demonstrate experimentally a
X-ray source, improving the image quality compared to unconstrained foil targets. Modelling demonstrates that a larger sheath field envelope around the perimeter of the constrained targets increases the proportion of electron current that recirculates through the target, driving a brighter source of X-rays.
To investigate the relative importance of 10 attributes identified in prior studies as essential for effective disaster medical responders and leaders.
Emergency and disaster medical response personnel (N=220) ranked 10 categories of disaster worker attributes in order of their importance in contributing to the effectiveness of disaster responders and leaders.
Attributes of disaster medical leaders and responders were rank ordered, and the rankings differed for leaders and responders. For leaders, problem-solving/decision-making and communication skills were the highest ranked, whereas teamwork/interpersonal skills and calm/cool were the highest ranked for responders.
The 10 previously identified attributes of effective disaster medical responders and leaders include personal characteristics and general skills in addition to knowledge of incident command and disaster medicine. The differences in rank orders of attributes for leaders and responders suggest that when applying these attributes in personnel recruitment, selection, and training, the proper emphasis and priority given to each attribute may vary by role. (Disaster Med Public Health Preparedness. 2019;13:700–703)
The x-ray energy emitted from laser-produced plasmas has been measured under various experimental conditions. Two Nd-glass lasers were used in separate experiments to focus pulsed laser light on planar targets. X-ray fluences were measured with newly developed silicon detector calorimeters. Results for various experimental conditions are reported in terms of the efficiency with which the laser light was converted to x-ray energy by plasma production.
To investigate whether amnestic mild cognitive impairment (aMCI) identified with visual memory tests conveys an increased risk of Alzheimer’s disease (risk-AD) and if the risk-AD differs from that associated with aMCI based on verbal memory tests.
4,771 participants aged 70.76 (SD = 6.74, 45.4% females) from five community-based studies, each a member of the international COSMIC consortium and from a different country, were classified as having normal cognition (NC) or one of visual, verbal, or combined (visual and verbal) aMCI using international criteria and followed for an average of 2.48 years. Hazard ratios (HR) and individual patient data (IPD) meta-analysis analyzed the risk-AD with age, sex, education, single/multiple domain aMCI, and Mini-Mental State Examination (MMSE) scores as covariates.
All aMCI groups (n = 760) had a greater risk-AD than NC (n = 4,011; HR range = 3.66 – 9.25). The risk-AD was not different between visual (n = 208, 17 converters) and verbal aMCI (n = 449, 29 converters, HR = 1.70, 95%CI: 0.88, 3.27, p = 0.111). Combined aMCI (n = 103, 12 converters, HR = 2.34, 95%CI: 1.13, 4.84, p = 0.023) had a higher risk-AD than verbal aMCI. Age and MMSE scores were related to the risk-AD. The IPD meta-analyses replicated these results, though with slightly lower HR estimates (HR range = 3.68, 7.43) for aMCI vs. NC.
Although verbal aMCI was most common, a significant proportion of participants had visual-only or combined visual and verbal aMCI. Compared with verbal aMCI, the risk-AD was the same for visual aMCI and higher for combined aMCI. Our results highlight the importance of including both verbal and visual memory tests in neuropsychological assessments to more reliably identify aMCI.
Various childhood social experiences have been reported to predict adult outcomes. However, it is unclear how different social contexts may influence each other's effects in the long run. This study examined the joint contribution of adolescent family and peer experiences to young adult wellbeing and functioning.
Participants came from the TRacking Adolescents’ Individual Lives Survey (TRAILS) study (n = 2230). We measured family and peer relations at ages 11 and 16 (i.e. family functioning, perceived parenting, peer status, peer relationship quality), and functioning as the combination of subjective wellbeing, physical and mental health, and socio-academic functioning at age 22. Using structural equation modelling, overall functioning was indicated by two latent variables for positive and negative functioning. Positive, negative and overall functioning at young adulthood were regressed on adolescent family experiences, peer experiences and interactions between the two.
Family experiences during early and mid-adolescence were most predictive for later functioning; peer experiences did not independently predict functioning. Interactions between family and peer experiences showed that both protective and risk factors can have context-dependent effects, being exacerbated or overshadowed by negative experiences or buffered by positive experiences in other contexts. Overall the effect sizes were modest at best.
Adolescent family relations as well as the interplay with peer experiences predict young adult functioning. This emphasizes the importance of considering the relative effects of one context in relation to the other.
Ultraviolet (UV) Solar spectral Irradiance (SSI) has been measured from orbit on a regular basis since the beginning of the space age. These observations span four Solar Cycles, and they are crucial for our understanding of the Sun-Earth connection and space weather. SSI at these wavelengths are the main drivers for the upper atmosphere including the production and destruction of ozone in the stratosphere. The instruments that measure UV SSI not only require good preflight calibration, but also need a robust method to maintain that calibration on orbit. We will give an overview of the catalog of current and former UV SSI measurements along with the calibration philosophy of each instrument and an estimation of the uncertainties in the published irradiances.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
The initiation and propagation of the 1993–95 surge of Bering Glacier, Alaska, U.S.A., was observed using ERS-1 synthetic aperture radar(SAR) imagery. Images were acquired before and during the surge, between November 1992 and October 1993. Terrain-corrected and co-registered imagery was used to measure the propagation of the surge front. Surface undulations interpreted to be evidence of accelerated flow, indicating surge initiation in late winter, were observed in the 26 March 1993 image. From 19 May to 25 August 1993, the mean propagation velocity of the surge front was 90 m d−1. The surge reached the terminus shortly after 25 August 1993. The central area of the calving terminus then advanced into proglacial Vitus Lake at a mean rate of 19 md−1 between 9 August and 18 October 1993. Feature matching was used to measure discrete velocity vectors between 9 August and 13 September; the vectors were kriged onto a uniform grid and used to compute the principal strain rates. Shattering of the calving front and dramatically increased iceberg calving were accompanied by high compressive strain rates immediately up-glacier from the calving front.
Because of the metastability of the 23S level of He I, a variety of effects can change the line strengths from pure recombination values in Seyfert galaxies (see Feldman and MacAlpine 1978). This occurs because the population which builds up in the 23S level can be collisionally excited to the 23P level, enhancing λ10830. The expected ratios of λ10830/λ5876 can be altered by internal or external reddening and vary with temperature, density and optical depth.
During the red supergiant (RSG) stage of massive star evolution, emission from dust and molecules allows the copious stellar winds to be studied in great detail. This help us understand not only the evolutionary stages of the star (which are highly dependent on mass loss rates), but also the morphology of the eventual supernova remnant. Maser emission from OH and H2O has been mapped with milli-arcsec resolution (using MERLIN and the EVN/global VLBI) around RSG including VY CMa, S Per and VX Sgr. The H2O masers originate in clouds accelerating away from the star and OH mainlines masers interleave the outer parts of the H2O maser shell. Zeeman splitting of OH maser lines reveals the orientation and strength of stellar-centred magnetic fields.
The aim of this analysis was to test if changes in insomnia symptoms and global sleep quality are associated with coinciding changes in depressed mood among older adults. We report on results yielded from secondary analysis of longitudinal data from a clinical trial of older adults (N = 49) aged 55 to 80 years who reported at least moderate levels of sleep problems. All measures were collected at baseline and after the trial ten weeks later. We computed change scores for two separate measures of disturbed sleep, the Athens Insomnia Scale (AIS) and the Pittsburgh Sleep Quality Index (PSQI), and tested their association with change in depressed mood (Beck Depression Inventory-II; BDI-II) in two separate linear regression models adjusted for biological covariates related to sleep (sex, age, body mass index, and NF-κB as a biological marker previously correlated with insomnia and depression). Change in AIS scores was associated with change in BDI-II scores (β = 0.38, p < 0.01). Change in PSQI scores was not significantly associated with change in BDI-II scores (β = 0.17, p = 0.26). Our findings suggest that improvements over ten weeks in insomnia symptoms rather than global sleep quality coincide with improvement in depressed mood among older adults.
The mean, trend and variability of net snow accumulation in firn cores are often used to validate model output, develop remote-sensing algorithms and quantify ice-sheet surface mass balance. Thus, accurately defining uncertainties associated with these in situ measurements is critical. In this study, we apply statistical simulation methods to quantify the uncertainty in firn-core accumulation data due to the uncertainty in depth–age scales. The methods are applied to a suite of firn cores from central West Antarctica. The results show that uncertainty in depth–age scales can give rise to spurious trends in accumulation that are the same order of magnitude as accumulation trends reported in West Antarctica. The depth–age scale uncertainties also significantly increase the apparent interannual accumulation variability, so these uncertainties must first be accounted for before using firn-core data to assess such processes as small-spatial-scale variability. Better quantification of error in accumulation will improve our ability to meaningfully compare firn-core data across different regions of the ice sheet, and provide appropriate targets for calibration and/or validation of model output and remote-sensing data.
The Wind River Range in Wyoming, USA, contains the largest concentration of glacial mass in the Rocky Mountains of the contiguous USA. Despite this distinction, only a few field or remotely sensed studies providing glacier volume changes have been published. The current study focuses on Continental Glacier located on the northern end of the range and uses two field datasets (high-accuracy GPS surface elevation points and ice-penetrating radar transects of the glacier bed) to create a three-dimensional model of glacier volume. Current surface elevations are compared with historical elevation data to calculate surface elevation change over time. An average thinning rate of 13.8 ± 7.8 m (0.30 ± 0.17 m a–1) between 1966 and 2012 was found. Surface elevation change rates varied across the glacier, ranging from +0.30 to –0.98 m a–1. Taking into account variable melt rates across the glacier, along with a glacial volume of 72.1 × 106 ± 10.8 × 106 m3, we estimate that Continental Glacier will be reduced in volume by 43% over the next 100 years and will disappear completely over the next 300–400 years, if current climatic conditions persist.