2,321 research outputs found
Mental time travel in dysphoria: Differences in the content and subjective experience of past and future episodes
Previous research has shown that depressed individuals demonstrate a number of biases in their ability to retrieve past events and simulate future events. The current study investigated the content and phenomenological experience of past and future events in dysphoric and non-dysphoric individuals. Results indicated that dysphoric, compared with non-dysphoric, individuals reported fewer positive events across both temporal directions. Furthermore, phenomenological characteristics ratings suggested that dysphoric individuals saw future, but not past, events as less vivid, coherent, sensorially detailed, bodily experienced, emotionally intense and important with respect to their life story and identity. These findings are discussed with reference to theories regarding the functions of ‘mental time travel’, in particular how the muted subjective experience of future episodes in depression may impair future planning, problem-solving and self regulation
Optimal Cosmic-Ray Detection for Nondestructive Read Ramps
Cosmic rays are a known problem in astronomy, causing both loss of data and
data inaccuracy. The problem becomes even more extreme when considering data
from a high-radiation environment, such as in orbit around Earth or outside the
Earth's magnetic field altogether, unprotected, as will be the case for the
James Webb Space Telescope (JWST). For JWST, all the instruments employ
nondestructive readout schemes. The most common of these will be "up the ramp"
sampling, where the detector is read out regularly during the ramp. We study
three methods to correct for cosmic rays in these ramps: a two-point difference
method, a deviation from the fit method, and a y-intercept method. We apply
these methods to simulated nondestructive read ramps with single-sample groups
and varying combinations of flux, number of samples, number of cosmic rays,
cosmic-ray location in the exposure, and cosmic-ray strength. We show that the
y-intercept method is the optimal detection method in the read-noise-dominated
regime, while both the y-intercept method and the two-point difference method
are best in the photon-noise-dominated regime, with the latter requiring fewer
computations.Comment: To be published in PASP. This paper is 12 pages long and includes 15
figure
High-resolution antenna near-field imaging and sub-THz measurements with a small atomic vapor-cell sensing element
Atomic sensing and measurement of millimeter-wave (mmW) and THz electric
fields using quantum-optical EIT spectroscopy of Rydberg states in atomic
vapors has garnered significant interest in recent years towards the
development of atomic electric-field standards and sensor technologies. Here we
describe recent work employing small atomic vapor cell sensing elements for
near-field imaging of the radiation pattern of a K-band horn antenna at
13.49 GHz. We image fields at a spatial resolution of and measure
over a 72 to 240 V/m field range using off-resonance AC-Stark shifts of a
Rydberg resonance. The same atomic sensing element is used to measure sub-THz
electric fields at 255 GHz, an increase in mmW-frequency by more than one order
of magnitude. The sub-THz field is measured over a continuous 100 MHz
frequency band using a near-resonant mmW atomic transition
How effective is school-based deworming for the community-wide control of soil-transmitted helminths?
Background: The London Declaration on neglected tropical diseases was based in part on a new World Health Organization roadmap to “sustain, expand and extend drug access programmes to ensure the necessary supply of drugs and other interventions to help control by 2020”. Large drug donations from the pharmaceutical industry form the backbone to this aim, especially for soil-transmitted helminths (STHs) raising the question of how best to use these resources. Deworming for STHs is often targeted at school children because they are at greatest risk of morbidity and because it is remarkably cost-effective. However, the impact of school-based deworming on transmission in the wider community remains unclear.
Methods: We first estimate the proportion of parasites targeted by school-based deworming using demography, school enrolment, and data from a small number of example settings where age-specific intensity of infection (either worms or eggs) has been measured for all ages. We also use transmission models to investigate the potential impact of this coverage on transmission for different mixing scenarios.
Principal Findings: In the example settings <30% of the population are 5 to <15 years old. Combining this demography with the infection age-intensity profile we estimate that in one setting school children output as little as 15% of hookworm eggs, whereas in another setting they harbour up to 50% of Ascaris lumbricoides worms (the highest proportion of parasites for our examples). In addition, it is estimated that from 40–70% of these children are enrolled at school.
Conclusions: These estimates suggest that, whilst school-based programmes have many important benefits, the proportion of infective stages targeted by school-based deworming may be limited, particularly where hookworm predominates. We discuss the consequences for transmission for a range of scenarios, including when infective stages deposited by children are more likely to contribute to transmission than those from adults
Breakfast and exercise contingently affect postprandial metabolism and energy balance in physically active males
The present study examined the impact of breakfast and exercise on postprandial metabolism, appetite and macronutrient balance.
A sample of twelve (blood variables n 11) physically active males completed four trials in a randomised, crossover design comprising a continued overnight fast followed by: (1) rest without breakfast (FR); (2) exercise without breakfast (FE); (3) breakfast consumption(1859 kJ) followed by rest (BR); (4) breakfast consumption followed by exercise (BE). Exercise was continuous, moderate-intensity running (expending approximately 2·9MJ of energy). The equivalent time was spent sitting during resting trials. A test drink (1500 kJ) was ingested on all trials followed 90 min later by an ad libitum lunch. The difference between the BR and FR trials in blood glucose time-averaged AUC following test drink consumption approached significance (BR: 4·33 (SEM 0·14) v. FR: 4·75 (SEM 0·16) mmol/l; P¼0·08); but it was not different between FR and FE (FE: 4·77 (SEM 0·14) mmol/l; P¼0·65); and was greater in BE (BE: 4·97 (SEM 0·13) mmol/l) v. BR(P¼0·012). Appetite following the test drink was reduced in BR v. FR (P¼0·006) and in BE v. FE (P¼0·029). Following lunch, the most positive energy balance was observed in BR and least positive in FE. Regardless of breakfast, acute exercise produced a less positive energy balance following ad libitum lunch consumption. Energy and fat balance is further reduced with breakfast omission. Breakfast improved the overall appetite responses to foods consumed later in the day, but abrogated the appetite suppressive effect of exercise
A systematic review of the quality of homeopathic clinical trials
BACKGROUND: While a number of reviews of homeopathic clinical trials have been done, all have used methods dependent on allopathic diagnostic classifications foreign to homeopathic practice. In addition, no review has used established and validated quality criteria allowing direct comparison of the allopathic and homeopathic literature. METHODS: In a systematic review, we compared the quality of clinical-trial research in homeopathy to a sample of research on conventional therapies using a validated and system-neutral approach. All clinical trials on homeopathic treatments with parallel treatment groups published between 1945–1995 in English were selected. All were evaluated with an established set of 33 validity criteria previously validated on a broad range of health interventions across differing medical systems. Criteria covered statistical conclusion, internal, construct and external validity. Reliability of criteria application is greater than 0.95. RESULTS: 59 studies met the inclusion criteria. Of these, 79% were from peer-reviewed journals, 29% used a placebo control, 51% used random assignment, and 86% failed to consider potentially confounding variables. The main validity problems were in measurement where 96% did not report the proportion of subjects screened, and 64% did not report attrition rate. 17% of subjects dropped out in studies where this was reported. There was practically no replication of or overlap in the conditions studied and most studies were relatively small and done at a single-site. Compared to research on conventional therapies the overall quality of studies in homeopathy was worse and only slightly improved in more recent years. CONCLUSIONS: Clinical homeopathic research is clearly in its infancy with most studies using poor sampling and measurement techniques, few subjects, single sites and no replication. Many of these problems are correctable even within a "holistic" paradigm given sufficient research expertise, support and methods
Toward Automation of the Supine Pressor Test for Preeclampsia
Preeclampsia leads to increased risk of morbidity and mortality for both mother and fetus. Most previous studies have largely neglected mechanical compression of the left renal vein by the gravid uterus as a potential mechanism. In this study, we first used a murine model to investigate the pathophysiology of left renal vein constriction. The results indicate that prolonged renal vein stenosis after 14 days can cause renal necrosis and an increase in blood pressure (BP) of roughly 30 mmHg. The second part of this study aimed to automate a diagnostic tool, known as the supine pressor test (SPT), to enable pregnant women to assess their preeclampsia development risk. A positive SPT has been previously defined as an increase of at least 20 mmHg in diastolic BP when switching between left lateral recumbent and supine positions. The results from this study established a baseline BP increase between the two body positions in nonpregnant women and demonstrated the feasibility of an autonomous SPT in pregnant women. Our results demonstrate that there is a baseline increase in BP of roughly 10-14 mmHg and that pregnant women can autonomously perform the SPT. Overall, this work in both rodents and humans suggests that (1) stenosis of the left renal vein in mice leads to elevation in BP and acute renal failure, (2) nonpregnant women experience a baseline increase in BP when they shift from left lateral recumbent to supine position, and (3) the SPT can be automated and used autonomously
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Linking Home-Based Child Care and State-Funded Preschool: The Community Connections Preschool Program (Illinois Action for Children): Evaluation Phase 1 — Implementation Study
The Community Connections preschool program (herein referred to as Community Connections) was developed to help prepare children in home-based child care for success in school and in life. It has three goals: (1) to make state prekindergarten classroom experiences available to children in home-based care, (2) to extend classroom learning experiences in the home-based care setting, and (3) to support infant and toddler development in participating providers' homes. In this model, state prekindergarten (Illinois "Preschool for All") classrooms provide half-day sessions four days per week for 3- and 4-year-old children coming from home-based child care. On the fifth day, the teachers visit children's care providers; delivering books and educational materials, modeling ways to extend curriculum activities, and discussing children's learning in the classroom. While preschoolers are in classrooms away from the home-based care setting, providers have precious time to focus on the needs of infants and toddlers in their care. Illinois Action for Children (herein referred to as IAFC) created the Community Connections program model in 2005 as Illinois was rapidly expanding its state prekindergarten program, which would ultimately change from serving exclusively at-risk children to become "Preschool for All." As the Preschool for All program grew, it became clear that large numbers of preschoolers in home-based care were being left out. Home-based care is the only option for many parents in low-wage jobs because those jobs tend to require non-traditional work hours — evenings, weekends, and changing shifts ““ when child care centers are closed. In Illinois, 67% of low-income single mothers with children under six work non-traditional hours (Illinois Action for Children, 2006). These mothers overwhelmingly choose home-based child care, usually provided by family, friends and neighbors. According to Illinois Child Care Assistance Program data, among families using the Child Care Assistance Program in Cook County, 58% have enrolled their children in home-based child care (22% in licensed homes and 36% in license-exempt Family, Friend and Neighbor care). While home-based child care is a significant community asset, preschool-age children tend to learn cognitive school readiness skills best in classroom settings (National Institute of Child Health and Human Development Early Child Care Research Network, 2002). In 2005, IAFC developed Community Connections to support home-based child care while adding a classroom-based experience to the children's day. This new program represents a third model through which state prekindergarten services are delivered in Illinois. The two most common models are part-day school-based programs and full-day programs delivered in conjunction with child care centers. As a third model, Community Connections has the potential to reach a large population of unserved children
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