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Radiotherapy clinical trials are at the forefront of modern-day prostate cancer patient management. Patients are reviewed during treatment by clinical oncologists or competent on-treatment review radiographers to minimise treatment toxicities. Clinical Research Radiographers (CRRs) routinely monitor and gather research data from patients participating in clinical trials.
The aim of this article is to evaluate the effectiveness of the CRR undertaking the on-treatment review of clinical trial patients.
An experienced CRR within the Northern Ireland Cancer Trials Network was supervised by a clinical oncologist to undertake the role of the on-treatment review of patients receiving radiotherapy for prostate cancer. The CRR explored published literature and compiled this written evaluation as part of their advanced practice learning.
The supervising clinical oncologist verified, following the planned period of supervised practice and academic study, that the CRR was competent to fulfil the role. Evidence of the beneficial synergistic impact of co-joining the roles was experienced at first hand during the undertaking of supervised practice.
Co-joining the roles and responsibilities of the CRR and the on-treatment review radiographer enhanced the quality of care offered to the patients participating in clinical trials.
We aimed to quantify the proportion of people receiving care for HIV-infection that are 50 years or older (older HIV patients) in Latin America and the Caribbean between 2000 and 2015 and to estimate the contribution to the growth of this population of people enrolled before (<50yo) and after 50 years old (yo) (⩾50yo). We used a series of repeated, cross-sectional measurements over time in the Caribbean, Central and South American network (CCASAnet) cohort. We estimated the percentage of patients retained in care each year that were older HIV patients. For every calendar year, we divided patients into two groups: those who enrolled before age 50 and after age 50. We used logistic regression models to estimate the change in the proportion of older HIV patients between 2000 and 2015. The percentage of CCASAnet HIV patients over 50 years had a threefold increase (8% to 24%) between 2000 and 2015. Most of the growth of this population can be explained by the increasing proportion of people that enrolled before 50 years and aged in care. These changes will impact needs of care for people living with HIV, due to multiple comorbidities and high risk of disability associated with aging.
The intensely active 2017 Atlantic basin hurricane season provided an opportunity to examine how climate drivers, including warming oceans and rising seas, exacerbated tropical cyclone hazards. The season also highlighted the unique vulnerabilities of populations residing on Small Island Developing States (SIDS) to the catastrophic potential of these storms. During 2017, 22 of the 29 Caribbean SIDS were affected by at least one named storm, and multiple SIDS experienced extreme damage. This paper aims to review the multiplicity of storm impacts on Caribbean SIDS throughout the 2017 season, to explicate the influences of climate drivers on storm formation and intensity, to explore the propensity of SIDS to sustain severe damage and prolonged disruption of essential services, to document the spectrum of public health consequences, and to delineate the daunting hurdles that challenged emergency response and recovery operations for island-based, disaster-affected populations. (Disaster Med Public Health Preparedness. 2019;13:5–17)
be an elliptic curve over a field
. There is a functor
from the category of finitely presented torsion-free left
-modules to the category of abelian varieties isogenous to a power of
, and a functor
in the opposite direction. We prove necessary and sufficient conditions on
for these functors to be equivalences of categories. We also prove a partial generalization in which
is replaced by a suitable higher-dimensional abelian variety over
Monozygotic (MZ) and dizygotic (DZ) twins participate in research that partitions variance in health, disease, and behavior into genetic and environmental components. However, there are other innovative roles for twins in medical research. One such way is involving MZ and/or DZ twins in co-twin control-designed randomized controlled trials (RCTs). To our knowledge, no reviews have been conducted that summarizes the involvement of twins in RCTs. Therefore, we conducted a systematic literature search using the U.S. Clinical Trials Database, NHS electronic databases, MEDLINE, EMBASE, and PsychINFO for RCTs on publications involving MZ and/or DZ twins as RCT participants. Out of the 186,027 clinical trials registered in the U.S. clinical trial register ClinicaTrails.gov, only six RCTs used twins as participants. From 1,598 articles identified in our search, 50 peer-reviewed English language publications met our pre-defined inclusion criteria. Sample sizes for RCTs have ranged from a total number of participants from 2 to 1,162; however, 32 (64%) studies had a sample size of 100 or less, and of those, 12 (24%) had fewer than 10. Both MZ and DZ twins have been recruited to the RCTs. In most instances (33/50) each twin from a pair were assigned to different study arms. Most of those studies included MZ twins only. Despite the methodological advantages, the use of MZ and DZ twins as participants in interventional RCTs appeared limited. The continuous development of innovative twin designs, especially RCTs, indicates that twin research can extend beyond the more widely recognized heritability estimates.
Interferometric synthetic aperture radar data show that Devon Ice Cap (DIC), northern Canada, is drained through a network of 11 glacier systems. More than half of all ice discharge is through broad flows that converge to the southeast of the ice cap, and these are grounded well below sea level at their termini. A calculation of the ice-cap mass budget reveals that the northwestern sector of DIC is gaining mass and that all other sectors are losing mass. We estimate that a 12 489 km2 section of the main ice cap receives 3.46±0.65 Gt of snowfall each year, and loses 3.11±0.21 Gt of water through runoff, and 1.43±0.03 Gt of ice through glacier discharge. Altogether, the net mass balance of DIC is –1.08±0.67 Gt a–1. This loss corresponds to a 0.003 mma–1 contribution to global sea levels, and is about half the magnitude of earlier estimates.
Water stored in and released from supraglacial lakes is an important factor when considering the seasonal and long-term evolution of the Greenland ice sheet. Here we use a radiative transfer model to estimate changes in the depth and volume of a supraglacial lake on the surface of Jakobshavn Isbræ, West Greenland, between 2002 and 2005. When compared to estimates of the lake depth determined from airborne lidar observations, we estimate that the root-mean-square departure of the modelled lake depths was 0.3 m during cloud-free conditions. The maximum lake area, depth and volume were 3.4 km2, 9.6 ±1.0 m and (18.6±3.7)×106 m3, respectively. When sequenced according to the number of positive degree-days (PDDs) accumulated prior to each image, we observe that the lake volume evolves in three distinct phases. At the start of the melting season, the rate of filling is slow; after approximately 80 PDDs the rate of filling increases by a factor ∽3, and after approximately 125 PDDs the lake drains rapidly. We estimate that the lake drains at a minimum rate of (2.66±0.53)×106 m3 d–1 over a 6 day period.
Rutford Ice Stream and Carlson Inlet are neighbouring glaciers in West Antarctica. Rutford Ice Stream flows at speeds greater than 350 m a−1, whereas Carlson Inlet, which has some similar dimensions and supports a similar driving stress, flows 10–50 times slower. We discuss a range of observations concerning Carlson Inlet, and conclude that there is good indirect evidence that it is a relict ice stream, which ceased streaming more than 240 years BP, but sufficiently recently that its surface morphology, basal water content and basal morphology still retain characteristics produced by streaming. An analysis of expected subglacial drainage pathways indicates that Carlson Inlet is not streaming because it is currently starved of subglacial water, which is currently directed beneath Rutford Ice Stream. This current state of water piracy by Rutford Ice Stream is, however, sensitive to minor thickness changes on the ice streams; a ∼120 m (<4%) thickening of Rutford Ice Stream would divert almost all the subglacial water in the system towards Carlson Inlet and could reactivate its flow. The result highlights the importance of subglacial drainage in controlling ice-stream evolution and the requirement for ice-sheet models to couple ice flow with subglacial drainage.
On an 11 m firn/ice core from Kongsvegen, Svalbard, we have used dielectric profiling (DEP) to measure electrical properties, and digital photography to measure a core optical stratigraphy (COS) profile. We also used a neutron-scattering probe (NP) to measure a density profile in the borehole from which the core was extracted. The NP- and DEP-derived density profiles were similar, showing large-scale (>30 cm) variation in the gravimetric densities of each core section. Fine-scale features (<10 cm) are well characterized by the COS record and are seen at a slightly lower resolution in both the DEP and NP records, which show increasing smoothing. A combination of the density accuracy of NP and the spatial resolution of COS provides a useful method of evaluating the shallow-density profile of a glacier, improving paleoclimate interpretation, mass-balance measurement and interpretation of radar returns.
Short-term ice-dynamical processes at Greenland’s Jakobshavn and Kangerdlugssuaq glaciers were studied using a 3 day time series of synthetic aperture radar data acquired during the 2011 European Remote-sensing Satellite-2 (ERS-2) 3 day repeat campaign together with modelled meteorological parameters. The time series spans the period March–July 2011 and captures the first ∼30% of the summer melting season. In both study areas, we observe velocity fluctuations at the lower ∼10 km of the glacier. At Jakobshavn Isbræ, where our dataset covers the first part of the seasonal calving-front retreat, we identify ten calving episodes, with a mean calving-front area loss of 1.29 ± 0.4 km2. Significant glacier speed-up was observed in the near-terminus area following all calving episodes. We identify changes in calving-front geometry as the dominant control on velocity fluctuations on both glaciers, apart from a <15% early-summer speed-up at Kangerdlugssuaq Glacier during a period of calving-front advance, which we attribute to enhanced surface melt-induced basal lubrication. Our 3 day velocity maps show new spatial characteristics of the ice melange flow variability in the Jakobshavn and Kangerdlugssuaq fjord systems, which are primarily controlled by calving-front dynamics and fjord geometry.
Understanding the climate response of the Antarctic Peninsula ice sheet is vital for accurate predictions of sea-level rise. However, since climate models are typically too coarse to capture spatial variability in local scale meteorological processes, our ability to study specific sectors has been limited by the local fidelity of such models and the (often sparse) availability of observations. We show that a high-resolution (5.5 km × 5.5 km) version of a regional climate model (RACMO2.3) can reproduce observed interannual variability in the Larsen B embayment sufficiently to enable its use in investigating long-term changes in this sector. Using the model, together with automatic weather station data, we confirm previous findings that the year of the Larsen B ice shelf collapse (2001/02) was a strong melt year, but discover that total annual melt production was in fact ~30% lower than 2 years prior. While the year before collapse exhibited the lowest melting and highest snowfall during 1980–2014, the ice shelf was likely pre-conditioned for collapse by a series of strong melt years in the 1990s. Melt energy has since returned to pre-1990s levels, which likely explains the lack of further significant collapse in the region (e.g. of SCAR Inlet).
Post-traumatic stress disorder (PTSD) is often associated with attention allocation and emotional regulation difficulties, but the brain dynamics underlying these deficits are unknown. The emotional Stroop task (EST) is an ideal means to monitor these difficulties, because participants are asked to attend to non-emotional aspects of the stimuli. In this study, we used magnetoencephalography (MEG) and the EST to monitor attention allocation and emotional regulation during the processing of emotionally charged stimuli in combat veterans with and without PTSD.
A total of 31 veterans with PTSD and 20 without PTSD performed the EST during MEG. Three categories of stimuli were used, including combat-related, generally threatening and neutral words. MEG data were imaged in the time-frequency domain and the network dynamics were probed for differences in processing threatening and non-threatening words.
Behaviorally, veterans with PTSD were significantly slower in responding to combat-related relative to neutral and generally threatening words. Veterans without PTSD exhibited no significant differences in responding to the three different word types. Neurophysiologically, we found a significant three-way interaction between group, word type and time period across multiple brain regions. Follow-up testing indicated stronger theta-frequency (4–8 Hz) responses in the right ventral prefrontal (0.4–0.8 s) and superior temporal cortices (0.6–0.8 s) of veterans without PTSD compared with those with PTSD during the processing of combat-related words.
Our data indicated that veterans with PTSD exhibited deficits in attention allocation and emotional regulation when processing trauma cues, while those without PTSD were able to regulate emotion by directing attention away from threat.
The Cosmic Background Imager (CBI) is an instrument designed to make images of the cosmic microwave background radiation and to measure its statistical properties on angular scales from about 3 arc minutes to one degree (spherical harmonic scales from l ˜ 4250 down to l ˜ 400). The CBI is a 13-element interferometer mounted on a 6 meter platform operating in ten 1-GHz frequency bands from 26 GHz to 36 GHz. The instantaneous field of view of the instrument is 45 arcmin (FWHM) and its resolution ranges from 3 to 10 arcmin; larger fields can be imaged by mosaicing. At this frequency and resolution, the primary foreground is due to discrete extragalactic sources, which are monitored at the Owens Valley Radio Observatory and subtracted from the CBI visibility measurements.
The instrument has been making observations since late 1999 of both primordial CMB fluctuations and the Sunyaev-Zeldovich effect in clusters of galaxies from its site at an altitude of 5080 meters near San Pedro de Atacama, in northern Chile. Observations will continue until August 2001 or later. We present preliminary results from the first few months of observations.
There are few published studies quantifying the volume of wildlife being traded through Singapore. We report on Singapore's involvement in the trade of avifauna listed on CITES based on government-reported data to CITES, with particular emphasis on Singapore's role in the trade of the globally threatened African grey parrot Psittacus erithacus. During 2005–2014 Singapore reported commercial import permits for 225,561 birds, from 35 countries, listed on CITES Appendices I and II, and the export of 136,912 similarly listed birds to 37 countries, highlighting the country's role as a major international transshipment hub for the global aviculture industry. Major exporters to Singapore included the Solomon Islands, the Netherlands, Taiwan, the Democratic Republic of the Congo, and South Africa. Major importers from Singapore included Taiwan, the United Arab Emirates and Japan. Singapore imported significant quantities of CITES-listed birds from African countries, including the Central African Republic, the Democratic Republic of the Congo, Guinea and South Africa, a number of which have a history of abuse of CITES export permits, discrepancies in reported trade data, or an acknowledged lack of wildlife law enforcement capacity. Significant discrepancies were detected between import and export figures of CITES-listed avifauna reported by Singapore and its trading partners. Based on these findings we present three recommendations to improve the regulation and monitoring of the trade in CITES-listed bird species in Singapore.
Dairy farms are under pressure to increase productivity while reducing environmental impacts. Effective fertilizer management practices are critical to achieve this. In the present study the effect of timing and rate of nitrogen (N) fertilizer application on pasture production and N losses, either via direct leaching of fertilizer N or indirectly through consumption of N in pasture and subsequent excretion via dairy cow grazing, was modelled. The Agricultural Production Systems Simulator (APSIM) was first tested with experimental data from N fertilizer response experiments conducted on a well-drained soil in the Waikato region of New Zealand. The model was then used in a 20-year simulation to investigate the effect of fertilizer management on the impacts on potential N leaching losses. Year-to-year variability was assessed by incorporating 20 years of climate data into the model. Modelling indicated that N fertilization at rates of 140 and 220 kg N/ha/year, applied in four split applications and avoiding application in winter months, could increase pasture yield on average by 2·2–3·0 t dry matter (DM)/ha (25–38%). There were some significant amounts of direct leaching in some years, related to environmental conditions. The maximum loss was as high as 61 kg N/ha at an N application rate of 220 kg N/ha/year, in a year with low pasture production and high rainfall following fertilizer application. In general, however, the risk of direct N leaching from applied fertilizer was low. It seems the main effect of N fertilization is to increase the risk of indirect N leaching, due to increased N intake and excretion. The modelling indicated that the major contribution to increased indirect N leaching risk was from the extra DM grown (more urine deposited per ha). Increased N concentration in the pasture due to fertilization and the resultant extra partitioning of excretal N to urine had only a minor effect on indirect leaching losses. The exception was N fertilizer applied in late winter/early spring (July), where fertilizer N (55 kg/ha) increased pasture N concentration by c. 25%, suggesting that the N concentration in urine patch areas could increase from c. 550 to 840 kg N/ha. Further measurements are required to test the hypothesis developed from the modelling that the main effect of N fertilizer on urinary N leaching is by increasing DM production rather than increasing pasture N concentration.
Different front-of-pack (FOP) labelling systems have been developed in Europe by industry and organisations concerned with health promotion. A study (n 2068) was performed to establish the extent to which inclusion of the most prevalent FOP systems – guideline daily amounts (GDA), traffic lights (TL), GDA+TL hybrid (HYB) and health logos (HL) – impact consumer perceptions of healthiness over and above the provision of a FOP basic label (BL) containing numerical nutritional information alone. The design included within- and between-subjects factors. The within-subjects factors were: food (pizzas, yogurts and biscuits), healthiness of the food (high health, medium health and low health) and the repeated measurements under BL and test FOP label conditions. The between-subjects factors were: the system (GDA, TL, GDA+TL hybrid, HL), portion size (typical portion size and a 50 % reduction of a typical portion) and country (the UK, Germany, Poland and Turkey). Although the FOP systems tested did result in small improvements for objective understanding under some conditions, there was little difference between the provision of an FOP label containing basic numerical nutritional information alone or between the various systems. Thus, any structured and legible presentation of key nutrient and energy information on the FOP label is sufficient to enable consumers to detect a healthier alternative within a food category when provided with foods that have distinctly different levels of healthiness. Future research should focus on developing greater understanding of the psychological and contextual factors that impact motivation and the opportunity to use the various FOP systems in real-world shopping settings.
Persons who develop tuberculosis (TB) may have subtle immune defects that could predispose to other intracellular bacterial infections (ICBIs). We obtained data on TB and five ICBIs (Chlamydia trachomatis, Salmonella spp., Shigella spp., Yersinia spp., Listeria monocytogenes) reported to the Tennessee Department of Health, USA, 2000–2011. Incidence rate ratios (IRRs) comparing ICBIs in persons who developed TB and ICBIs in the Tennessee population, adjusted for age, sex, race and ethnicity were estimated. IRRs were not significantly elevated for all ICBIs combined [IRR 0·87, 95% confidence interval (CI) 0·71–1·06]. C. trachomatis rate was lowest in the year post-TB diagnosis (IRR 0·17, 95% CI 0·04–0·70). More Salmonella infections occurred in extrapulmonary TB compared to pulmonary TB patients (IRR 14·3, 95% CI 1·67–122); however, this appeared to be related to HIV co-infection. TB was not associated with an increased risk of other ICBIs. In fact, fewer C. trachomatis infections occurred after recent TB diagnosis. Reasons for this association, including reduced exposure, protection conferred by anti-TB drugs or macrophage activation by Mycobacterium tuberculosis infection warrant further investigation.
True findings about schizophrenia remain elusive; many findings are not replicated and conflicting results are common. Well-conducted systematic reviews have the ability to make robust, generalizable conclusions, with good meta-analyses potentially providing the closest estimate of the true effect size. In this paper, we undertake a systematic approach to synthesising the available evidence from well-conducted systematic reviews on schizophrenia.
Reviews were identified by searching Medline, EMBASE, CINAHL, Current Contents and PsycINFO. The decision to include or exclude reviews, data extraction and quality assessments were conducted in duplicate. Evidence was graded as high quality if reviews contained large samples and robust results; and as moderate quality if reviews contained imprecision, inconsistency, smaller samples or study designs that may be prone to bias.
High- and moderate-quality evidence shows that numerous psychosocial and biomedical treatments are effective. Patients have relatively poor cognitive functioning, and subtle, but diverse, structural brain alterations, altered electrophysiological functioning and sleep patterns, minor physical anomalies, neurological soft signs, and sensory alterations. There are markers of infection, inflammation or altered immunological parameters; and there is increased mortality from a range of causes. Risk for schizophrenia is increased with cannabis use, pregnancy and birth complications, prenatal exposure to Toxoplasma gondii, childhood central nervous system viral infections, childhood adversities, urbanicity and immigration (first and second generation), particularly in certain ethnic groups. Developmental motor delays and lower intelligence quotient in childhood and adolescence are apparent.
We conclude that while our knowledge of schizophrenia is very substantial, our understanding of it remains limited.