To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Using an ensemble of close- and long-range remote sensing, lake bathymetry and regional meteorological data, we present a detailed assessment of the geometric changes of El Morado Glacier in the Central Andes of Chile and its adjacent proglacial lake between 1932 and 2019. Overall, the results revealed a period of marked glacier down wasting, with a mean geodetic glacier mass balance of −0.39 ± 0.15 m w.e.a−1 observed for the entire glacier between 1955 and 2015 with an area loss of 40% between 1955 and 2019. We estimate an ice elevation change of −1.00 ± 0.17 m a−1 for the glacier tongue between 1932 and 2019. The increase in the ice thinning rates and area loss during the last decade is coincident with the severe drought in this region (2010–present), which our minimal surface mass-balance model is able to reproduce. As a result of the glacier changes observed, the proglacial lake increased in area substantially between 1955 and 2019, with bathymetry data suggesting a water volume of 3.6 million m3 in 2017. This study highlights the need for further monitoring of glacierised areas in the Central Andes. Such efforts would facilitate a better understanding of the downstream impacts of glacier downwasting.
Social jetlag (SJ) occurs when sleep-timing irregularities from social or occupational demands conflict with endogenous sleep–wake rhythms. SJ is associated with evening chronotype and poor mental health, but mechanisms supporting this link remain unknown. Impaired ability to retrieve extinction memory is an emotion regulatory deficit observed in some psychiatric illnesses. Thus, SJ-dependent extinction memory deficits may provide a mechanism for poor mental health. To test this, healthy male college students completed 7–9 nights of actigraphy, sleep questionnaires, and a fear conditioning and extinction protocol. As expected, greater SJ, but not total sleep time discrepancy, was associated with poorer extinction memory. Unexpectedly, greater SJ was associated with a tendency toward morning rather than evening chronotype. These findings suggest that deficient extinction memory represents a potential mechanism linking SJ to psychopathology and that SJ is particularly problematic for college students with a greater tendency toward a morning chronotype.
We describe 14 yr of public data from the Parkes Pulsar Timing Array (PPTA), an ongoing project that is producing precise measurements of pulse times of arrival from 26 millisecond pulsars using the 64-m Parkes radio telescope with a cadence of approximately 3 weeks in three observing bands. A comprehensive description of the pulsar observing systems employed at the telescope since 2004 is provided, including the calibration methodology and an analysis of the stability of system components. We attempt to provide full accounting of the reduction from the raw measured Stokes parameters to pulse times of arrival to aid third parties in reproducing our results. This conversion is encapsulated in a processing pipeline designed to track provenance. Our data products include pulse times of arrival for each of the pulsars along with an initial set of pulsar parameters and noise models. The calibrated pulse profiles and timing template profiles are also available. These data represent almost 21 000 h of recorded data spanning over 14 yr. After accounting for processes that induce time-correlated noise, 22 of the pulsars have weighted root-mean-square timing residuals of
in at least one radio band. The data should allow end users to quickly undertake their own gravitational wave analyses, for example, without having to understand the intricacies of pulsar polarisation calibration or attain a mastery of radio frequency interference mitigation as is required when analysing raw data files.
We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band (
), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
International research shows that media can increase knowledge, raise public awareness and reduce stigma relating to mental health.
Following the broadcast of a documentary on national television featuring interviews with young people who had experienced mental health difficulties and suicidal behaviour, an anonymous online survey, aimed at examining public perceptions of the impact of a television documentary, was conducted, using a mixed methods approach.
2311 people completed the survey. Of those who watched the documentary and answered the closed questions (n = 854), 94% stated that the documentary will positively impact young people’s mental health and well-being. The majority (91%) stated that the documentary will encourage young people to talk to someone if experiencing difficulties and 87% indicated it will help to reduce stigma associated with mental health. Viewers had a 5% higher level of intention to seek help than non-viewers. Participants indicated that the identifiable personal stories and discourse around stigma and shame, and the increased understanding and awareness gained, had the most profound impact on them.
These findings indicate that a documentary addressing mental health and suicidal behaviour, which incorporates real life identifiable stories of resilience and recovery, has the potential to impact positively on emotional well-being and general mood, to reduce stigma related to mental health and to encourage help-seeking behaviour. Documentaries including these concepts, with a public mental health focus and a consistent message, incorporating pre- and post-evaluations, and customisation for target audiences in compliance with current media recommendations, should be considered.
Hot carrier based methods constitute a valuable approach for efficient and silicon compatible sub-bandgap photodetection. Although, hot electron excitation and transfer have been studied extensively on traditional materials such as Au and Ti, reports on alternative materials such as titanium nitride (TiN) are rare. Here, we perform hot hole photodetection measurements on a p-Si/metal thin film junction using Ti, Au and TiN. This material is of interest as it constitutes a refractory alternative to Au which is an important property for plasmonic applications where high field intensities can occur. In contrast to Au, a TiN/Si junction does not suffer from metal diffusion into the Si, which eases the integration with current Si-fabrication techniques. This work shows that a backside illuminated p-Si/TiN system can be used for efficient hot hole extraction in the IR, allowing for a responsivity of 1 mA/W at an excitation wavelength of 1250 nm and at zero bias. Via a comparison between TiN and other commonly used materials such as Au, the origin of this comparably high photoresponse can be traced back to be directly linked to a thin TiO2-x interfacial layer allowing for a distinct hot-hole transfer mechanism. Moreover, the fabrication of TiN nanodisk arrays is demonstrated which bears great promise to further boost the device efficiency.
Methods to stimulate appetite in the sick or elderly remains a challenge with few safe therapeutic options. Ghrelin is an orexigenic hormone, increasing appetite and subsequent food intake. It has received considerable attention as a therapeutic target to stimulate food intake in patients with anorexia. The identification of food-grade bioactives with proven orexigenic effects would mark significant progress in the treatment of disease-related malnutrition. This study therefore investigated the effects of two milk-derived ghrelinergic peptides on appetite and energy intake in healthy humans.
A single-blind, placebo-controlled, 3-arm (placebo, casein bioactive MF1145 and whey bioactive UL-2-141) cross-over trial was conducted in healthy male volunteers. Participants received 26 mg/kg of both the bioactives and placebo. The main outcome measures were energy & protein intake from a set breakfast and ad libitum lunch and subjective appetite sensations as assessed by visual analogue scale (VAS). Basal and postprandial levels of active ghrelin (AG) were measured. Dietary intakes were analysed using Nutritics software. Statistical analyses were performed in R.
Overall, 22 male participants (mean age 27 years) were included, average BMI was 24.6 kg/m2, (19.8 to 30.2 kg/m2). Mean energy and protein intakes at lunch when treated with placebo were 1343 kcal (95% CI: 1215–1471 kcal) and 74 g (95% CI: 66–81 g), respectively. Energy and protein intakes were not significantly different from placebo for either treatment (p = 0.918, p = 0.319 for UL-2-141 and p = 0.889, p = 0.959 for MF1145, respectively). Similarly, appetite, hunger and satiety responses on VAS were not significantly different from placebo for either treatment. AG peak post-lunch on placebo was 653 pg/ml (95% CI: 511–794 pg/ml). Treatment with UL-2-141 resulted in 139 pg/ml reduction in post-prandial AG compared to placebo and treatment with MF1145 resulted in 114 pg/ml reduction compared to placebo. This pattern was significant for both treatments (p = 0.021 and p = 0.045, respectively) however when controlling for fasting-AG, the pattern was no longer significant (p = 0.590 and p = 0.877 respectively). Pre-prandial AG peaks were not significantly different across treatments.
While these peptides have previously demonstrated ghrelinergic effects in rats, no effect on appetite or food intake in humans was identified by this study. This may be attributable to the small sample size or low dose. However, since healthy adults are often not in tune with their own physiological hunger, they may not respond strongly to simple physiological modulators and repeating the study in subjects with established anorexia may be prudent.
A vagrant black-browed albatross Thalassarche melanophris bred with a grey-headed albatross T. chrysostoma on Marion Island at least four times between 2000 and 2009 (and continued to return to the colony until at least 2019). The eggs failed to hatch in three breeding attempts, but the pair fledged a chick in the 2006/07 breeding season. Genetic sexing identified the black-browed albatross as female and she shared all eight sampled microsatellite alleles with the chick, whereas the grey-headed albatross social parent did not match the chick. The fledgling was banded and re-sighted in its natal breeding colony in 2016 and 2018, when it displayed an intermediate black-browed x grey-headed albatross phenotype, similar to a putative hybrid photographed at sea off Australia. These results suggest that the black-browed albatross cuckolded its social mate with another grey-headed albatross in 2006/07. The failures of the other three breeding attempts at the egg stage possibly indicate genetic incompatibility with the social partner.
Consumers prefer bright, cherry-red retail beef. Retailers often mark down the price of discolored beef for quick sale. However, following this practice could result in a net loss of revenue if consumer willingness to pay (WTP) for nondiscolored beef is negatively affected by the presence of discolored beef in the consumer choice set. Through a hypothetical online survey and a controlled in-person experiment, we determine that marketing discolored beef together with nondiscolored beef increases most consumers’ evaluation of, but not their WTP for, nondiscolored beef.
The Salkovskis (1999) model of obsessive compulsive disorder (OCD), which emphasizes the role of inflated responsibility, has proven highly influential in both the understanding and treatment of OCD.
This study aimed to empirically test several core processes of this model.
The individual components of the model were measured using multiple indicators in a sample of undergraduate students (n = 170), and confirmatory factor analyses were used to ascertain the most reliable, valid and theoretically consistent latent variables. Structural equation modelling was used to test proposed relations between latent constructs in the model.
The inflated responsibility model was a good fit for the data in the present sample. As predicted by the model, misinterpretations of intrusive thoughts as indicating personal responsibility fully mediated the relationships between responsibility beliefs and counterproductive safety strategies, neutralizing actions and mood changes.
The Salkovksis (1999) inflated responsibility model of OCD is empirically supported in the present sample of undergraduate students, lending support to the proposed mechanisms in the model and supporting prior evidence.
The diet of most adults is low in fish and, therefore, provides limited quantities of the long-chain, omega-3 fatty acids (LCn-3FAs), eicosapentaenoic and docosahexaenoic acids (EPA, DHA). Since these compounds serve important roles in the brain, we sought to determine if healthy adults with low-LCn-3FA consumption would exhibit improvements in neuropsychological performance and parallel changes in brain morphology following repletion through fish oil supplementation.
In a randomized, controlled trial, 271 mid-life adults (30–54 years of age, 118 men, 153 women) consuming ⩽300 mg/day of LCn-3FAs received 18 weeks of supplementation with fish oil capsules (1400 mg/day of EPA and DHA) or matching placebo. All participants completed a neuropsychological test battery examining four cognitive domains: psychomotor speed, executive function, learning/episodic memory, and fluid intelligence. A subset of 122 underwent neuroimaging before and after supplementation to measure whole-brain and subcortical tissue volumes.
Capsule adherence was over 95%, participant blinding was verified, and red blood cell EPA and DHA levels increased as expected. Supplementation did not affect performance in any of the four cognitive domains. Exploratory analyses revealed that, compared to placebo, fish oil supplementation improved executive function in participants with low-baseline DHA levels. No changes were observed in any indicator of brain morphology.
In healthy mid-life adults reporting low-dietary intake, supplementation with LCn-3FAs in moderate dose for moderate duration did not affect neuropsychological performance or brain morphology. Whether salutary effects occur in individuals with particularly low-DHA exposure requires further study.
One generation's experience of childhood maltreatment is associated with that of the next. However, whether this intergenerational transmission is specific to distinct forms of maltreatment and what factors may contribute to its continuity remains unclear. Borderline personality pathology is predicted by childhood maltreatment and characterized by features (e.g., dysregulated emotion, relationship instability, impulsivity, and inconsistent appraisals of others) that may contribute to its propagation. Among 364 older adults and 573 of their adult children (total n = 937), self-reported exposure to distinct forms of childhood maltreatment (i.e., emotional, physical, and sexual abuse, and emotional and physical neglect as assessed by the Childhood Trauma Questionnaire) showed homotypic and heterotypic associations across generations with little evidence that latent factors unique to specific forms of maltreatment show generational continuity. General nonspecific indices of childhood maltreatment showed evidence of intergenerational transmission after accounting for demographic factors and parent socioeconomic status (b = 0.126, p = 9.21 × 10−4). This continuity was partially mediated by parental borderline personality pathology (assessed longitudinally through a variety of measures and sources, indirect effect: b = 0.031, 95% confidence interval [0.003, 0.060]). The intergenerational continuity of childhood maltreatment may largely represent general risk for nonspecific maltreatment that may, in part, be propagated by borderline personality pathology and/or shared risk factors.
The provision of artificial nests can improve the conservation status of threatened bird species that are limited by nest-site availability. The shortage of natural cavity nesting sites is one factor limiting the population growth of the Southern Ground Hornbill Bucorvus leadbeateri. In an 1,800 km2 study area in north-eastern South Africa, 31 wooden nest-boxes were installed during 2002–2015. We investigated the relationships between nests, as well as environmental and social factors, with breeding. Generalised linear mixed models were fitted to the observational data and identified positive relationships between breeding attempts and each of home range size and the previous year’s rainfall; as well as positive relationships between breeding success (amongst the groups that attempt breeding) and each of earlier breeding, nest height and thickness of the nest cavity wall. The provision of nest-boxes increased the number of breeding groups and although breeding success also increased initially, it later declined as the density of breeding groups increased above 20 groups. Although nest-boxes alone did not increase overall breeding success, they are an effective conservation tool to enhance the population of Southern Ground Hornbills if spaced optimally, to enhance reproductive output in areas where suitable nest-sites are scarce or lacking.
Water exposures in healthcare settings and during healthcare delivery can place patients at risk for infection with water-related organisms and can potentially lead to outbreaks. We aimed to describe Centers for Disease Control and Prevention (CDC) consultations involving water-related organisms leading to healthcare-associated infections (HAIs).
Retrospective observational study.
We reviewed internal CDC records from January 1, 2014, through December 31, 2017, using water-related terms and organisms, excluding Legionella, to identify consultations that involved potential or confirmed transmission of water-related organisms in healthcare. We determined plausible exposure pathways and routes of transmission when possible.
Of 620 consultations during the study period, we identified 134 consultations (21.6%), with 1,380 patients, that involved the investigation of potential water-related HAIs or infection control lapses with the potential for water-related HAIs. Nontuberculous mycobacteria were involved in the greatest number of investigations (n = 40, 29.9%). Most frequently, investigations involved medical products (n = 48, 35.8%), and most of these products were medical devices (n = 40, 83.3%). We identified a variety of plausible water-exposure pathways, including medication preparation near water splash zones and water contamination at the manufacturing sites of medications and medical devices.
Water-related investigations represent a substantial proportion of CDC HAI consultations and likely represent only a fraction of all water-related HAI investigations and outbreaks occurring in US healthcare facilities. Water-related HAI investigations should consider all potential pathways of water exposure. Finally, healthcare facilities should develop and implement water management programs to limit the growth and spread of water-related organisms.
In 2014/2015, International Medical Corps (IMC) operated two Ebola Treatment Units (ETUs) in Liberia and three in Sierra Leone when the Ebola virus disease epidemic killed over 11,000 people across Liberia, Sierra Leone and Guinea. As Ebola cases declined in Liberia, IMC Psychosocial teams transitioned to working in communities highly affected by the epidemic. This article describes IMC's experience with developing and implementing a community-based mental health and psychosocial group intervention in a rural, severely affected Liberian town – Mawah – where 46 out of approximately 800 community members were infected, 39 of whom died. In this paper, we present how the group intervention, named ‘Social Reconnection Groups’, was developed and implemented. We then discuss intervention strengths, challenges, key lessons learnt and recommendations for how Social Reconnection Groups can be adapted for use in similar settings.
The rocky intertidal zone has a long history of ecological study with barnacles frequently serving as a model system to explore foundational theories. Parasites are often ignored in community ecology studies, and this particularly holds for true for the rocky intertidal zone. We explore the role of the isopod parasite, Hemioniscus balani, on its host, the acorn barnacle, Chthamalus fissus. We use the currencies of biomass and reproduction measured at the individual level, then applied to the population level, to evaluate the importance of this parasite to barnacle populations. We found H. balani can comprise substantial biomass in ‘apparent’ barnacle populations, sometimes even equaling barnacle biomass. Additionally, parasite reproduction sometimes matched barnacle reproduction. Thus, parasites divert substantial energy flow from the barnacle population and to near-shore communities in the form of parasite larvae. Parasites appeared to decrease barnacle reproduction per area. Potentially, this parasite may control barnacle populations, depending on the extent to which heavily infected barnacle populations contribute to barnacle populations at larger scales. These findings regarding the importance of a particular parasite for host population dynamics in this well studied ecosystem call for the integration of disease dynamics into community ecological studies of the rocky intertidal zone.
To date, Ireland has been a leading light in the provision of youth mental health services. However, cognisant of the efforts of governmental and non-governmental agencies working in youth mental health, there is much to be done. Barriers into care as well as discontinuity of care across the spectrum of services remain key challenges. This editorial provides guidance for the next stage of development in youth mental care and support that will require significant national engagement and resource investment.
Invasive plants may dramatically impact forest ecosystems by establishing dense populations and suppressing the recruitment of native tree species. One invasive shrub currently spreading throughout eastern deciduous forests of North America, Japanese barberry (Berberis thunbergii DC), may be limiting tree recruitment in stands where it invades. Once established, B. thunbergii becomes densely populated within forest understories and suppresses native plants by competing for limited resources, altering soil conditions, and changing the understory microclimate. To quantify native seedling inhibition caused by B. thunbergii invasion, we conducted an observational study on seedling abundance within forest plots that were either invaded or not invaded by B. thunbergii and used survey data to generate Bayesian models of native seedling densities along gradients of increasing B. thunbergii stem counts and aboveground plant dry mass. Model outputs predicted that B. thunbergii–invaded plots had 82% lower seedling densities compared with uninvaded plots. Native tree seedling densities were very low even in areas with moderate B. thunbergii density, suggesting that reduced tree seedling densities are observed even at low densities of invasion. Our findings indicate that forests invaded with B. thunbergii harbor substantially lower densities of native tree seedlings, with potentially significant long-term consequences for forest ecological integrity, biodiversity, and ecosystem services.