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The COVID-19 pandemic has created an unprecedented global crisis, necessitating drastic changes to living conditions, social life, personal freedom and economic activity. No study has yet examined the presence of psychiatric symptoms in the UK population under similar conditions.
We investigated the prevalence of COVID-19-related anxiety, generalised anxiety, depression and trauma symptoms in the UK population during an early phase of the pandemic, and estimated associations with variables likely to influence these symptoms.
Between 23 and 28 March 2020, a quota sample of 2025 UK adults aged 18 years and older, stratified by age, gender and household income, was recruited by online survey company Qualtrics. Participants completed standardised measures of depression, generalised anxiety and trauma symptoms relating to the pandemic. Bivariate and multivariate associations were calculated for demographic and health-related variables.
Higher levels of anxiety, depression and trauma symptoms were reported compared with previous population studies, but not dramatically so. Anxiety or depression and trauma symptoms were predicted by young age, presence of children in the home, and high estimates of personal risk. Anxiety and depression were also predicted by low income, loss of income and pre-existing health conditions in self and others. Specific anxiety about COVID-19 was greater in older participants.
This study showed a modest increase in the prevalence of mental health problems in the early stages of the pandemic, and these problems were predicted by several specific COVID-related variables. Further similar surveys, particularly of those with children at home, are required as the pandemic progresses.
Amazon's Mechanical Turk is widely used for data collection; however, data quality may be declining due to the use of virtual private servers to fraudulently gain access to studies. Unfortunately, we know little about the scale and consequence of this fraud, and tools for social scientists to detect and prevent this fraud are underdeveloped. We first analyze 38 studies and show that this fraud is not new, but has increased recently. We then show that these fraudulent respondents provide particularly low-quality data and can weaken treatment effects. Finally, we provide two solutions: an easy-to-use application for identifying fraud in the existing datasets and a method for blocking fraudulent respondents in Qualtrics surveys.
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.
The need for hollow microneedle arrays is important for both drug delivery and wearable sensor applications; however, their fabrication poses many challenges. Hollow metal microneedle arrays residing on a flexible metal foil substrate were created by combining additive manufacturing, micromolding, and electroplating approaches in a process we refer to as electromolding. A solid microneedle with inward facing ledge was fabricated with a two photon polymerization (2PP) system utilizing laser direct write (LDW) and then molded with polydimethylsiloxane. These molds were then coated with a seed layer of Ti/Au and subsequently electroplated with pulsed deposition to create hollow microneedles. An inward facing ledge provided a physical blocking platform to restrict deposition of the metal seed layer for creation of the microneedle bore. Various ledge sizes were tested and showed that the resulting seed layer void could be controlled via the ledge length. Mechanical properties of the PDMS mold was adjusted via the precursor ratio to create a more ductile mold that eliminated tip damage to the microneedles upon removal from the molds. Master structures were capable of being molded numerous times and molds were able to be reused. SEM/EDX analysis showed that trace amounts of the PDMS mold were transferred to the metal microneedle upon removal. The microneedle substrate showed a degree of flexibility that withstood over 100 cycles of bending from side to side without damaging. Microneedles were tested for their fracture strength and were capable of puncturing porcine skin and injecting a dye.
Disasters occur without warning and can have devastating consequences. Emergency preparedness can reduce negative effects. It is especially important that parents prepare, as children are particularly vulnerable after disasters. This study tested 2 hypotheses: (1) adults with more children are likely to be better prepared than those with fewer or no children because greater caretaking is linked to greater perceived threat of disaster leading to greater preparedness and (2) the strength of this mediational link varies as a function of parental self-efficacy.
Data from an online survey about human-made disasters (terrorism) with a community convenience sample were used to test the hypothesis that perceived threat mediates the relationship between parental status (number of children cared for) and preparedness behaviors, moderated by level of self-efficacy for emergency preparedness.
A bootstrapping analysis with relevant covariates supported the hypothesized mediating effect of threat on the relationship between parental status and preparedness. This relationship was strengthened at higher levels of parental preparedness self-efficacy.
The results of this study are particularly relevant for preparedness interventions. Because threat leads to preparedness, particularly for parents with high self-efficacy, it is important to focus attention on factors that can improve parents’ sense of self-efficacy. (Disaster Med Public Health Preparedness. 2018; 12: 345–351)
Mandatory I fortification in bread was introduced in Australia in 2009 in response to the re-emergence of biochemical I deficiency based on median urinary I concentration (UIC)<100 µg/l. Data on the I status of lactating mothers and their infants in Australia are scarce. The primary aim of this study was to assess the I status, determined by UIC and breast milk I concentration (BMIC), of breast-feeding mothers in South Australia and UIC of their infants. The secondary aim was to assess the relationship between the I status of mothers and their infants. The median UIC of the mothers (n 686) was 125 (interquartile range (IQR) 76–200) µg/l and median BMIC (n 538) was 127 (IQR 84–184) µg/l. In all, 38 and 36 % of the mothers had a UIC and BMIC below 100 µg/l, respectively. The median UIC of infants (n 628) was 198 (IQR 121–296) µg/l, and 17 % had UIC<100 µg/l. Infant UIC was positively associated with maternal UIC (β 0·26; 95 % CI 0·14, 0·37, P<0·001) and BMIC (β 0·85; 95 % CI 0·66, 1·04, P<0·001) at 3 months postpartum after adjustment for gestational age, parity, maternal secondary and further education, BMI category and infant feeding mode. The adjusted OR for infant UIC<100 µg/l was 6·49 (95 % CI 3·80, 11·08, P<0·001) in mothers with BMIC<100 µg/l compared with those with BMIC≥100 µg/l. The I status of mothers and breast-fed infants in South Australia, following mandatory I fortification, is indicative of I sufficiency. BMIC<100 µg/l increased the risk of biochemical I deficiency in breast-fed infants.
To determine whether the seasonality of surgical site infections (SSIs) can be explained by changes in temperature.
Retrospective cohort analysis.
The National Inpatient Sample database.
All hospital discharges with a primary diagnosis of SSI from 1998 to 2011 were considered cases. Discharges with a primary or secondary diagnoses of specific surgeries commonly associated with SSIs from the previous and current month served as our “at risk” cohort.
We modeled the national monthly count of SSI cases both nationally and stratified by region, sex, age, and type of institution. We used data from the National Climatic Data Center to estimate the monthly average temperatures for all hospital locations. We modeled the odds of having a primary diagnosis of SSI as a function of demographics, payer, location, patient severity, admission month, year, and the average temperature in the month of admission.
SSI incidence is highly seasonal, with the highest SSI incidence in August and the lowest in January. During the study period, there were 26.5% more cases in August than in January (95% CI, 23.3–29.7). Controlling for demographic and hospital-level characteristics, the odds of a primary SSI admission increased by roughly 2.1% per 2.8°C (5°F) increase in the average monthly temperature. Specifically, the highest temperature group, >32.2°C (>90°F), was associated with an increase in the odds of an SSI admission of 28.9% (95% CI, 20.2–38.3) compared to temperatures <4.4°C (<40°F).
At population level, SSI risk is highly seasonal and is associated with warmer weather.
For the first time, we are reporting the growth of high quality single crystalline 3C-SiC epitaxially on hexagonal silicon carbide substrates using Hot Filament Chemical Vapor Deposition (HF-CVD) on full 4” wafers. Rocking curve X-Ray diffraction (XRD) measurements resulted in a full width at half maximum (FWHM) as low as 88 arcsec for a 40 µm thick layer. We achieved this quality using a carefully optimized process making use of the additional degrees of freedom the hot filaments create. The filaments allow for precursor pre-cracking and a tuning of the vertical thermal gradient, which creates an improved thermal field compared to conventional Chemical Vapor Deposition. Growth rates of up to 8 µm/h were achieved with standard silane and propane chemistry, and further increased to 20 µm/h with chlorinated chemistry. The use of silicon carbide substrates promises superior layer quality compared to silicon substrates due to their better match in lattice parameters and thermal expansion coefficients. High resolution scanning electron microscopy, X-Ray rocking measurements, and micro-Raman allow us to assess the crystalline quality of our material and to compare it to layers grown on low-cost silicon substrates. Hall measurements reveal a linear increase of the charge carrier density in the material with the flow of nitrogen gas as a dopant. Electron densities above 10-18 cm-3 have been reached.
Remingtonocetidae are Eocene archaeocetes that represent a unique experiment in cetacean evolution. They possess long narrow skulls, long necks, fused sacra, and robust hind limbs. Previously described remingtonocetids are known from middle Eocene Lutetian strata in Pakistan and India. Here we describe a new remingtonocetid, Rayanistes afer, n. gen. n. sp., recovered from a middle to late Lutetian interval of the Midawara Formation in Egypt. The holotype preserves a sacrum with four vertebral centra; several lumbar and caudal vertebrae; an innominate with a complete ilium, ischium, and acetabulum; and a nearly complete femur. The ilium and ischium of Rayanistes are bladelike, rising sharply from the body of the innominate anterior and posterior to the acetabulum, and the acetabular notch is narrow. These features are diagnostic of Remingtonocetidae, but their development also shows that Rayanistes had a specialized mode of locomotion. The expanded ischium is larger than that of any other archaeocete, supporting musculature for powerful retraction of the hind limbs during swimming. Posteriorly angled neural spines on lumbar vertebrae and other features indicate increased passive flexibility of the lumbus. Rayanistes probably used its enhanced lumbar flexibility to increase the length of the power stroke during pelvic paddling. Recovery of a remingtonocetid in Egypt broadens the distribution of Remingtonocetidae and shows that protocetids were not the only semiaquatic archaeocetes capable of dispersal across the southern Tethys Sea.
Kalisch and colleagues highlight coping potential (CP) as a principle resilience mechanism during event engagement. We complement this discussion by exploring generative implicit CP self-models, arguably emerging during “resting-state,” subsequent and prior to events. Resting-state affords a propitious environment for Bayesian learning, wherein appraisals/reappraisals may update active inferential CP self-models, which then mediate appraisal style organization and resilience factor valuation.
The concealed and widely dispersed nests of the rare and endangered Yellow-eyed Penguin Megadyptes antipodes, or “hoiho”, have been considered to reflect an essential requirement for the visual isolation of nest sites from conspecifics. However, this may be a consequence of selection for habitat features that provide protection from insolation, thereby minimising the risk of heat stress. To help improve the understanding of hoiho nesting requirements and the effectiveness of habitat restoration, we aimed to determine whether visual isolation from conspecifics or protection from insolation is the primary driver of hoiho nest site selection. We compared the mean maximum distance of visibility and the mean percentage insolation cover of active nests with randomly sampled unused sites in flax Phormium tenax and Hebe elliptica coastal scrub at Boulder Beach, and in coastal forest at Hinahina Cove, New Zealand, 2006–2007. Results of univariate tests and the evaluation of logistic regression models suggested that the amount of insolation cover was more important than visibility for hoiho nest site selection, particularly in flax and scrub. In addition, Spearman's correlations indicated that decreasing insolation cover significantly increased the visibility of nests in the forest habitat, and had a similar effect on inter-nest distance in flax. We infer that hoiho nest site selection and distribution are influenced primarily by the location and density of micro-habitat features (particularly within 1 m of the ground) that provide optimal protection from insolation, possibly along with other important features such as a firm backing structure. Strong selection for these features results in the typical but non-essential visual isolation of nest sites from conspecifics. Restoration of nesting habitats with a relatively high density and diversity of vegetation and solid structures within 1 m of the ground may eventually provide an optimal availability and quality of suitable nest sites.
Nanoscale metal–insulator–metal (MIM) diodes consisting of a nanoscale-thickness insulator layer sandwiched between two dissimilar metal layers offer the potential for very high frequency alternating current to direct current signal rectification. Active nanoscale tuning of electronic tunneling through the insulator layer to form point contact diodes has previously been limited to barriers composed of soft organic films due to the force limitations of conductive-atomic force microscopy. In this paper, MIM diodes with oxide-based insulators are formed in situ with sub-nanometer depth precision and characterized using a nanoindenter equipped with electrical testing capabilities. Simultaneous measurement of both electrical and nano-mechanical information is accomplished in an MIM stack of the form Nb/Nb2O5/boron-doped diamond nanoindenter tip. Using this technique, we show that the diode behavior can be electromechanically tuned over a range of more than 1 V at equivalent currents via small changes in indentation depth and the results can be modeled using a Fowler–Nordheim approximation.
Objectives: A linked evidence approach (LEA) is the synthesis of systematically acquired evidence on the accuracy of a medical test, its impact on clinical decision making and the effectiveness of consequent treatment options. We aimed to assess the practical utility of this methodology and to develop a decision framework to guide its use.
Methods: As Australia has lengthy experience with LEA, we reviewed health technology assessment (HTA) reports informing reimbursement decisions by the Medical Services Advisory Committee (August 2005 to March 2012). Eligibility was determined according to predetermined criteria and data were extracted on test characteristics, evaluation methodologies, and reported difficulties. Fifty percent of the evidence-base was independently analyzed by a second reviewer.
Results: Evaluations of medical tests for diagnostic (62 percent), staging (27 percent), and screening (6 percent) purposes were available for eighty-nine different clinical indications. Ninety-six percent of the evaluations used either the full LEA methodology or an abridged version (where evidence is linked through to management changes but not patient outcomes). Sixty-one percent had the full evidence linkage. Twenty-five percent of test evaluations were considered problematic; all involving LEA (n = 22). Problems included: determining test accuracy with an imperfect reference standard (41 percent); assessing likely treatment effectiveness in test positive patients when the new test is more accurate than the comparator (18 percent); and determining probable health benefits in those symptomatic patients ruled out using the test (13 percent). A decision framework was formulated to address these problems.
Conclusions: LEA is useful for evaluating medical tests but a stepped approach should be followed to determine what evidence is required for the synthesis.
Commensal microflora play many roles within the mammalian gastrointestinal tract (GIT) that benefit host physiology by way of direct or indirect interactions with mucosal surfaces. Commensal flora comprises members across all microbial phyla, although predominantly bacterial, with population dynamics varying with host species, genotype, and environmental factors. Little is known, however, about the complex mechanisms regulating host–commensal interactions that underlie this mutually beneficial relationship and how alterations in the microbiome may influence host development and susceptibility to infection. Research into the gut microbiome has intensified as it becomes increasingly evident that symbiont–host interactions have a significant impact on mucosal immunity and health. Furthermore, evidence that microbial populations vary significantly throughout the GIT suggest that regional differences in the microbiome may also influence immune function within distinct compartments of the GIT. Postpartum colonization of the GIT has been shown to have a direct effect on mucosal immune system development, but information is limited regarding regional effects of the microbiome on the development, activation, and maturation of the mucosal immune system. This review discusses factors influencing the colonization and establishment of the microbiome throughout the GIT of newborn calves and the evidence that regional differences in the microbiome influence mucosal immune system development and maturation. The implications of this complex interaction are also discussed in terms of possible effects on responses to enteric pathogens and vaccines.