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Early life stress (ELS) is a risk factor for the development of depression in adolescence; the mediating neurobiological mechanisms, however, are unknown. In this study, we examined in early pubertal youth the associations among ELS, cortisol stress responsivity, and white matter microstructure of the uncinate fasciculus and the fornix, two key frontolimbic tracts; we also tested whether and how these variables predicted depressive symptoms in later puberty. A total of 208 participants (117 females; M age = 11.37 years; M Tanner stage = 2.03) provided data across two or more assessment modalities: ELS; salivary cortisol levels during a psychosocial stress task; diffusion magnetic resonance imaging; and depressive symptoms. In early puberty there were significant associations between higher ELS and decreased cortisol production, and between decreased cortisol production and increased fractional anisotropy in the uncinate fasciculus. Further, increased fractional anisotropy in the uncinate fasciculus predicted higher depressive symptoms in later puberty, above and beyond earlier symptoms. In post hoc analyses, we found that sex moderated several additional associations. We discuss these findings within a broader conceptual model linking ELS, emotion dysregulation, and depression across the transition through puberty, and contend that brain circuits implicated in the control of hypothalamic–pituitary–adrenal axis function should be a focus of continued research.
Heavy alcohol use is pervasive and one of our most significant global health burdens. Early theories posited that certain alcohol response phenotypes, notably low sensitivity to alcohol (‘low-level response’) imparts risk for alcohol use disorder (AUD). However, other theories, and newer measures of subjective alcohol responses, have challenged that contention and argued that high sensitivity to some alcohol effects are equally important for AUD risk. This study presents results of a unique longitudinal study in 294 young adult non-dependent drinkers examined with alcohol and placebo testing in the laboratory at initial enrolment and repeated 5 years later, with regular follow-up intervals assessing AUD (trial registration: http://clinicaltrials.gov/ct2/show/NCT00961792). Findings showed that alcohol sedation was negatively correlated with stimulation across the breath alcohol curve and at initial and re-examination testing. A higher rather than lower alcohol response phenotype was predictive of future AUD. The findings underscore a new understanding of factors increasing vulnerability to AUD.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
The spatial-intensity profile of light reflected during the interaction of an intense laser pulse with a microstructured target is investigated experimentally and the potential to apply this as a diagnostic of the interaction physics is explored numerically. Diffraction and speckle patterns are measured in the specularly reflected light in the cases of targets with regular groove and needle-like structures, respectively, highlighting the potential to use this as a diagnostic of the evolving plasma surface. It is shown, via ray-tracing and numerical modelling, that for a laser focal spot diameter smaller than the periodicity of the target structure, the reflected light patterns can potentially be used to diagnose the degree of plasma expansion, and by extension the local plasma temperature, at the focus of the intense laser light. The reflected patterns could also be used to diagnose the size of the laser focal spot during a high-intensity interaction when using a regular structure with known spacing.
Theorists and researchers have linked resilience with a host of positive psychological and physical health outcomes. This paper examines perceptions of resilience and physical health symptoms in a sample of individuals exposed to multiple community disasters following involvement in integrated mental health services.
A multiwave naturalistic design was used to follow 762 adult clinic patients (72% female; 28% minority status), ages 18-92 years (mean age=40 years), who were evaluated for resilience and physical health symptoms prior to receiving services and at 1, 3, and 6 months’ follow-up.
Data indicated increases in perceptions of resilience and decreased physical health symptoms reported over time. Results also indicated that resilience predicted physical health symptoms, such that resilience and physical health symptoms were negatively associated (ie, improved resilience was associated with decreases in physical health symptoms). These effects were primarily observed for those individuals with previous exposure to natural disasters.
Findings provide correlational evidence for behavioral health treatment provided as part of a stepped-care, collaborative model in reducing physical health symptoms and increasing resilience post-disaster. Controlled trials are warranted. (Disaster Med Public Health Preparedness. 2019;13:223–229)
Introduction: Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common presentation to the emergency department (ED) accounting for significant morbidity, mortality and health care resource usage. In Alberta, a provincial care pathway was recently developed to provide an evidence informed approach to managing patients with an UGIBs in the ED. Pantoprazole infusions are a commonly used treatment despite evidence that suggests they are generally not indicated prior to endoscopy in the ED. The goal of this project was to optimize management of patients with a NVUGIB, in particular reduce pre-endoscopy pantoprazole infusions. Methods: In July 2016, we implemented a multi-faceted intervention to optimize management of ED patients with NVUGIB including 1. de-emphasizing IV pantoprazole infusions in the ED, 2. clinical decision support (CDS) embedded (for endoscopy, disposition and transfusions) within the order set and 3. educating clinicians about the care pathway. We used a pre/post-order set design, analyzing 391 days pre and 189 days post-order set changes. Data was extracted from our fully integrated electronic health records system. The primary outcome was the % of patients receiving IV pantoprazole infusion ordered by an emergency physician (EP) among all patients with NVUGIB. Secondary outcomes included % transfused with hgb >70g/L and whether using the GIB order set impacted management of NVUGIB patients. Results: In the 391 days pre-order set changes, there were 2165 patients included and in the 189 days post-order set changes, there were 901 patients. For baseline characteristics, patients in the post-order set change group were significantly older (64.4 yrs vs 60.9 yrs p-value=0.0016) and had a lower hgb (115 vs 118, p-value=0.049) but otherwise for gender, measures of severity of illness (systolic blood pressure, heart rate, CTAS, % admitted) there were no significantly differences. For the primary outcome, in the pre-order set phase, 47.1% received a pantoprazole infusion ordered by an EP, compared to 31.5% in the post-order phase, for an absolute reduction of 15.6% (p-value= <0.001). For the secondary outcomes, transfusion rates were similar pre/post (22.08% vs 22.75%). Significant inter-site variability exists with respect to the reduction in pantoprazole infusion rates across the four sites (-23.3% to +6.12%). Conclusion: Our interventions resulted in a significant overall reduction in pantoprazole infusions in ED patients with NVUGIB. Reductions in pantoprazole infusions varied significantly across the different sites, future work in our department will explore and address this variability. Keys to the success of this project included engaging clinicians as well as leveraging the SCM order sets as well as the provincial care pathway. Although there were no changes in transfusion rates, it in unclear if this a function of the CDS not being effective or whether these transfusions were clinically indicated.
We present first results from a coordinated multiwavelength study of the neutron star low-mass X-ray binary EXO 0748 676. Fast UV, X-ray, and optical data were obtained including both spectral and timing information. We discuss how this study allows us to probe the temperature distribution within the binary and hence the geometry and efficiency of X-ray irradiation.
Due to the interlocking nature of the ovine cervix semen deposition during cervical insemination takes place at the external cervical os resulting in commercially unacceptable conception rates when using frozen/thawed semen. During natural mating it is not known whether the cervix plays a pro-active role in the transport of semen into the uterine lumen. Endogenous and seminal prostaglandins and coitally-released oxytocin may contribute to the stimulation of the cervix and enhance the capture and movement of semen through the cervical canal. Electromyographical studies showed spontaneous motility of the ovine cervix and uterus with the greatest activity recorded during the periovulatory period (Garcia-Villar et al., 1982). Recent advances in fibre-optics and video technology allowed us to make direct observations and time-sequence recordings of cervical activity in fully conscious ewes under minimal restraint. The aim of the study was to observe and record for the first time the response of the external os cervix before and immediately after ram stimulation both with and without intromission, during artificial deposition of semen and after administration of exogenous oxytocin.
Early life stress (ELS) is a significant risk factor for the emergence of internalizing problems in adolescence. Beginning in adolescence, females are twice as likely as males to experience internalizing disorders. The present study was designed to examine sex differences in the association between ELS and internalizing problems in early pubertal adolescents, and whether and how corticolimbic function and connectivity may underlie these associations. Fifty-nine early pubertal males and 78 early pubertal females, ages 9–13 years (all Tanner Stage 3 or below) underwent functional magnetic resonance imaging as they performed an emotion label task that robustly interrogates corticolimbic function. Participants were also interviewed about their experience of ELS. Females exhibited a positive association between ELS and internalizing problems, whereas males exhibited no such association. Whole-brain and amygdala region of interest analyses indicated that whereas females exhibited a positive association between ELS and the ventrolateral prefrontal cortex during implicit emotion regulation, males showed no such association. Activation in these regions was positively associated with internalizing problems in females but not males; however, activation in these regions did not mediate the association between ELS and internalizing problems. Finally, both boys and girls exhibited an association between ELS and increased negative connectivity between the right ventrolateral prefrontal cortex and bilateral amygdala. Using a carefully characterized sample of early pubertal adolescents, the current study highlights important sex differences in the development of corticolimbic circuitry during a critical period of brain development. These sex differences may play a significant role in subsequent risk for internalizing problems.
In previous studies (Mylne et al, 1992; McKelvey et al, 1997)) we have shown that the recovery of sheep embryos via the cervix can be facilitated by combining topical application of prostaglandin E2 (PGE2) to the external os cervix with systemic oestradiol treatment (E2) to dilate the cervix. The combined PGE2 and E2 treatment did not inhibit early embryo development (McEvoy et al, 1996) but conceptus viability was not determined. The objective of the present study was to test the viability of embryos recovered transcervically following dilation of the cervix with exogenous hormones and provide quantative data on their subsequent ability to establish normal pregnancies.
The Ronne polynya formed in the Weddell Sea, Antarctica, during the period November 1997−February 1998 to an extent not seen previously in the 25 years of all-weather satellite observations. The vessel HMS Endurance traversed the polynya region and took sea-ice, physical oceanographic and meteorological measurements during January and early February 1998. These observations, together with satellite imagery and weather records, were analyzed to determine the causes of the anomalous condition observed and to provide comparisons for numerical modeling experiments. The polynya area, analyzed from satellite imagery, showed a linear, nearly constant, increase with time from mid-November 1997 through February 1998. It had a maximum open-water area of 3 × 105 km2 and extended 500 km north of the Ronne Ice Shelf (at 76° S) to 70° S. The ice and snow structure of floes at the northern edge of the polynya showed the ice there had formed in the previous mid- to late winter (October 1997 or earlier) and had been advected there either from the eastern Weddell Sea or from the front of the Ronne Ice Shelf. Analyses of the wind fields showed anomalous spring-summer wind fields in the polynya year, with a strong southerly to southwesterly component compared to the mean easterly winds typical of summer conditions. These southerly wind conditions, in both magnitude and direction, therefore account for the drift of ice northward. The predominant summer easterly winds usually fill the southern Weddell Sea with ice from the east, and the high-albedo surfaces reflect the solar radiation, preventing warming of the surface ocean waters and consequent sea-ice melt. Instead, high incident solar radiation from November 1997 to February 1998 was absorbed by the open water, rather than being reflected, thereby both melting ice and preventing ice formation, and thereby sustaining the polynya. We conclude that open-water-albedo feedback is necessary to allow the observed polynya formation, since similar drift conditions prevail in winter (arising from southerly winds also) and usually result in extensive new ice formation in front of the Ronne Ice Shelf. The strong southerly winds therefore have quite opposing seasonal effects, leading to high ice production in winter as usually found, and extensive open water if they occur in spring and summer, as seen in this atypical event in 1997/98. In this case, the atypical southerly winds may be associated with an El Niño-Southern Oscillation (ENSO)-induced atmospheric circulation pattern.
We have used micrometeorological data collected at Hailey Research Station, Antarctica, to estimate monthly totals of snow sublimation. Direct sublimation from the snow surface is calculated using bulk-transfer formulae, while the sublimation of blowing snow is estimated using a model for suspended-particle number density and individual particle sublimation rates. During the winter months, sublimation losses are negligible, but between November and March sublimation removes around 25% of the snowfall. Surface sublimation and sublimation of blowing snow make roughly equal contributions to this total. Estimates of sublimation using micrometeorological data agree well with estimates made from daily snow-stake measurements.
The unique phenotypic and genetic aspects of obsessive-compulsive (OCD) and attention-deficit/hyperactivity disorder (ADHD) among individuals with Tourette syndrome (TS) are not well characterized. Here, we examine symptom patterns and heritability of OCD and ADHD in TS families.
OCD and ADHD symptom patterns were examined in TS patients and their family members (N = 3494) using exploratory factor analyses (EFA) for OCD and ADHD symptoms separately, followed by latent class analyses (LCA) of the resulting OCD and ADHD factor sum scores jointly; heritability and clinical relevance of the resulting factors and classes were assessed.
EFA yielded a 2-factor model for ADHD and an 8-factor model for OCD. Both ADHD factors (inattentive and hyperactive/impulsive symptoms) were genetically related to TS, ADHD, and OCD. The doubts, contamination, need for sameness, and superstitions factors were genetically related to OCD, but not ADHD or TS; symmetry/exactness and fear-of-harm were associated with TS and OCD while hoarding was associated with ADHD and OCD. In contrast, aggressive urges were genetically associated with TS, OCD, and ADHD. LCA revealed a three-class solution: few OCD/ADHD symptoms (LC1), OCD & ADHD symptoms (LC2), and symmetry/exactness, hoarding, and ADHD symptoms (LC3). LC2 had the highest psychiatric comorbidity rates (⩾50% for all disorders).
Symmetry/exactness, aggressive urges, fear-of-harm, and hoarding show complex genetic relationships with TS, OCD, and ADHD, and, rather than being specific subtypes of OCD, transcend traditional diagnostic boundaries, perhaps representing an underlying vulnerability (e.g. failure of top-down cognitive control) common to all three disorders.
Sexual assault is a global concern with post-traumatic stress disorder (PTSD), one of the common sequelae. Early intervention can help prevent PTSD, making identification of those at high risk for the disorder a priority. Lack of representative sampling of both sexual assault survivors and sexual assaults in prior studies might have reduced the ability to develop accurate prediction models for early identification of high-risk sexual assault survivors.
Data come from 12 face-to-face, cross-sectional surveys of community-dwelling adults conducted in 11 countries. Analysis was based on the data from the 411 women from these surveys for whom sexual assault was the randomly selected lifetime traumatic event (TE). Seven classes of predictors were assessed: socio-demographics, characteristics of the assault, the respondent's retrospective perception that she could have prevented the assault, other prior lifetime TEs, exposure to childhood family adversities and prior mental disorders.
Prevalence of Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD associated with randomly selected sexual assaults was 20.2%. PTSD was more common for repeated than single-occurrence victimization and positively associated with prior TEs and childhood adversities. Respondent's perception that she could have prevented the assault interacted with history of mental disorder such that it reduced odds of PTSD, but only among women without prior disorders (odds ratio 0.2, 95% confidence interval 0.1–0.9). The final model estimated that 40.3% of women with PTSD would be found among the 10% with the highest predicted risk.
Whether counterfactual preventability cognitions are adaptive may depend on mental health history. Predictive modelling may be useful in targeting high-risk women for preventive interventions.
We utilized de-identified data to evaluate increases in four outcomes during influenza outbreak periods (IOPs) including: hospitalization, intensive care unit admission, mechanical ventilation or death for adults aged 18 years or older with medically attended acute respiratory illnesses (MAARI) admitted to any of Maryland's 50 acute-care hospitals over 12 years. Weekly numbers of positive influenza tests in the Maryland area were obtained from the US Center for Disease Control and Prevention interactive website. The fewest consecutive weeks around the peak week containing at least 85% of the positive tests defined the IOP. Weekly counts of individual study outcomes were positively correlated with regional weekly counts of positive influenza tests during all the IOPs over 12 years. Also, rate ratios comparing daily occurrences of each study outcome between the IOP and non-IOP were significantly elevated. These results confirm conclusions of previous studies that influenza outbreaks are clearly associated with deaths and increased use of advanced medical resources by patients with MAARI. These data analyses suggest that increased efforts to develop more effective influenza vaccines and therapeutics should be a priority.
Early in the history of schistosomiasis research, children under 5 years of age were known to be infected. Although this problem was recognized over 100 years ago, insufficient action has been taken to address this issue. Under current policy, such infected children only receive their first antiparasitic treatment (praziquantel – PZQ) upon entry into primary school as current mass drug administration programmes typically target school-aged children. For many infected children, they will wait up to 6 years before receiving their first medication and significant schistosomiasis-related morbidity may have already established. This inequity would not be accepted for other diseases. To unveil some of the reasons behind this neglect, it is paramount to understand the intricate historical relationship between schistosomiasis and British Imperial medicine, to underline its lasting influence on today's public health priorities. This review presents a perspective on the historical neglect of paediatric schistosomiasis, focusing on important gaps that persist from the early days after discovery of this parasite. Looking to end this inequity, we address several issues that need to be overcome to move forward towards the lasting success of schistosomiasis control and elimination efforts.
The suggestion that patches of basal ice may freeze to the bed of a glacier due to certain regelation effects has been tested in the laboratory by applying high hydrostatic pressures to ice samples at the pressure-melting point. During compression, ice temperatures follow the pressure-melting point closely, but after rapid decompression the ice temperature at first returns only half to three-quarters of the way to the pressure-melting point, after which it appears to warm by thermal conduction from outside the ice sample. If the moving ice at the base of a glacier behaves in the same way as it is exposed to changing pressure fields, frozen patches at bedrock are to be expected.
Records of strain variations in a tunnel beneath Glacier d’Argentière show two types of strain events. The first is a rapid jump or offset in the recorded strain, while the second are strain excursions, initiated by a change in strain over a period up to ten seconds, followed by a gradual recovery to the original strain over some minutes. It is suggested that the offset events are due to nearby stress release due to fracturing of frozen patches of ice at the bedrock while the strain-excursion events show the more distant adjustment of the glacial bed to the former events due to the time lags associated with changes of water-film thickness and regelation heat flow.
Temperature records from slations on the west roast of the Antarctic Peninsula show a very high level of interannual variability and, over the last 50 years, larger warming trends than are seen elsewhere in Antarctica. in this paper we investigate the role of atmospheric circulation variability and sea-ice extent variations in driving these changes. Owing to a lack of independent data, the reliability of Antarctic atmospheric analyses produced in the 1950s and 1960s cannot be readily established, but examination of the available data suggests that there has been an increase in the northerly component of the circulation over the Peninsula since the late 1950s. Few observations of sea-ice extent are available prior to 1973, but the limited data available indicate that the ice edge to the west of the Peninsula lay to the north of recently observed extremes during the very cold conditions prevailing in the late 1950s. The ultimate cause of the atmospheric-circulation changes remains to be determined and may lie outside the Antarctic region.
Accurate models of X-ray absorption and re-emission in partly stripped ions are necessary to calculate the structure of stars, the performance of hohlraums for inertial confinement fusion and many other systems in high-energy-density plasma physics. Despite theoretical progress, a persistent discrepancy exists with recent experiments at the Sandia Z facility studying iron in conditions characteristic of the solar radiative–convective transition region. The increased iron opacity measured at Z could help resolve a longstanding issue with the standard solar model, but requires a radical departure for opacity theory. To replicate the Z measurements, an opacity experiment has been designed for the National Facility (NIF). The design uses established techniques scaled to NIF. A laser-heated hohlraum will produce X-ray-heated uniform iron plasmas in local thermodynamic equilibrium (LTE) at temperatures
eV and electron densities
. The iron will be probed using continuum X-rays emitted in a
diameter source from a 2 mm diameter polystyrene (CH) capsule implosion. In this design,
of the NIF beams deliver 500 kJ to the
mm diameter hohlraum, and the remaining
directly drive the CH capsule with 200 kJ. Calculations indicate this capsule backlighter should outshine the iron sample, delivering a point-projection transmission opacity measurement to a time-integrated X-ray spectrometer viewing down the hohlraum axis. Preliminary experiments to develop the backlighter and hohlraum are underway, informing simulated measurements to guide the final design.
The collective response of electrons in an ultrathin foil target irradiated by an ultraintense (
) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture’, inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.