1,965 research outputs found
Project Frozo: A Solution to the Cold-Chain Problem
Project Frozo has designed an ultra-low temperature portable freezer capable of storing 500 COVID-19 vaccine vials for global distribution. The device does not require external power, and utilizes a combination of vacuum insulation panels, aerogel, and phase change material to maintain a storage volume temperature of -70°C for over 10 days. This duration of time was determined by running a one-dimensional transient heat transfer simulation with a constant ambient temperature of 48.89°C (120°F). Construction of a prototype is underway which will be used to perform physical testing and validate the simulation results. The design will enable cost effective distribution of the COVID-19 vaccine on a global scale. The design follows guidelines set by The Setty Family Foundation: 2022 Applied Engineering Challenge as well as the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) standards. Vaccine storage requirements were determined using public information provided by Pfizer. Project Frozo’s design will function as the final storage system for vaccines prior to doses being administered to recipients
The Feeding Practices and Structure Questionnaire: development and validation of age appropriate versions for infants and toddlers
Background
In order to measure and understand trajectories of parental feeding practices and their relationship with child eating and weight, it is desirable to perform assessment from infancy and across time, in age-appropriate ways. While many feeding practices questionnaires exist, none is presently available that enables tracking of feeding practices from infancy through childhood. The aim of the study was to develop a version of the Feeding Practices and Structure Questionnaire (FPSQ) for parents with infants and toddlers (< 2 years) to be used in conjunction with the original FPSQ for older children (≥2 years) to measure feeding practices related to non-responsiveness and structure across childhood.
Methods
Constructs and items for the FPSQ for infants and toddlers were derived from the existing and validated FPSQ for older children and supplemented by a review of the literature on infant feeding questionnaires. Following expert review, two versions of the questionnaire were developed, one for milk feeding parents and one for solid feeding parents. Data from two studies were combined (child ages 0–24 months) to test the derived constructs with Confirmatory Factor Analysis for the milk feeding (N = 731) and solid feeding (N = 611) versions.
Results
The milk feeding version consisted of four factors (18 items) and showed acceptable model fit and good internal reliability: ‘feeding on demand vs. feeding routine’ (α = 0.87), ‘using food to calm’ (α = 0.87), ‘persuasive feeding’ (α = 0.71), ‘parent-led feeding’ (α = 0.79). The same four factors showed acceptable model fit for the solid feeding version (21 items), likewise with good internal reliability (α = 0.74, 0.86, 0.85, 0.84 respectively). Two additional factors (13 items) were developed for the solid feeding version that appeared developmentally appropriate only for children aged 12 months or older: ‘family meal environment’ (α = 0.81) and ‘using (non-)food rewards’ (α = 0.92). The majority of factor-factor correlations were in line with those of the original FPSQ.
Conclusions
The FPSQ milk and solid feeding versions are the first measures specifically developed as precursors to the FPSQ to measure parental feeding practices in children < 2 years, particularly practices related to non-responsiveness and structure. Further validation in more diverse samples is required
Red Light-Emitting Electrochemical Cells Employing Pyridazine-Bridged Cationic Diiridium Complexes
A rigid dinuclear Ir(III) complex showing high photoluminescence quantum yield in pure films was successfully used to fabricate light-emitting electrochemical cells with and without ionic liquid additives. The devices showed nearly instantaneous electroluminescence after biasing and maximum quantum yield approaching 1%. The lifetime of the devices was found to be limited to approximately 20 hours, which we correlated with the irreversible oxidation of the complex as seen from electrochemical measurements. This work validates the use of highly luminescent dinuclear iridium complexes in light-emitting electrochemical cells. Future studies will pursue materials with more efficient photoluminescence as well as improved electrochemical stability
Face-to-face: Social work and evil
The concept of evil continues to feature in public discourses and has been reinvigorated in some academic disciplines and caring professions. This article navigates social workers through the controversy surrounding evil so that they are better equipped to acknowledge, reframe or repudiate attributions of evil in respect of themselves, their service users or the societal contexts impinging upon both. A tour of the landscape of evil brings us face-to-face with moral, administrative, societal and metaphysical evils, although it terminates in an exhortation to cultivate a more metaphorical language. The implications for social work ethics, practice and education are also discussed
Revealing natural relationships among arbuscular mycorrhizal fungi: culture line BEG47 represents Diversispora epigaea, not Glomus versiforme
Background: Understanding the mechanisms underlying biological phenomena, such as evolutionarily conservative trait inheritance, is predicated on knowledge of the natural relationships among organisms. However, despite their enormous ecological significance, many of the ubiquitous soil inhabiting and plant symbiotic arbuscular mycorrhizal fungi (AMF, phylum Glomeromycota) are incorrectly classified.
Methodology/Principal Findings:
Here, we focused on a frequently used model AMF registered as culture BEG47. This fungus is a descendent of the ex-type culture-lineage of Glomus epigaeum, which in 1983 was synonymised with Glomus versiforme. It has since then been used as ‘G. versiforme BEG47’. We show by morphological comparisons, based on type material, collected 1860–61, of G. versiforme and on type material and living ex-type cultures of G. epigaeum, that these two AMF species cannot be conspecific, and by molecular phylogenetics that BEG47 is a member of the genus Diversispora.
Conclusions: This study highlights that experimental works published during the last >25 years on an AMF named ‘G. versiforme’ or ‘BEG47’ refer to D. epigaea, a species that is actually evolutionarily separated by hundreds of millions of years from all members of the genera in the Glomerales and thus from most other commonly used AMF ‘laboratory strains’. Detailed redescriptions substantiate the renaming of G. epigaeum (BEG47) as D. epigaea, positioning it systematically in the order Diversisporales, thus enabling an evolutionary understanding of genetical, physiological, and ecological traits, relative to those of other AMF. Diversispora epigaea is widely cultured as a laboratory strain of AMF, whereas G. versiforme appears not to have been cultured nor found in the field since its original description
Feeding a Fussy Eater: Examining Longitudinal Bidirectional Relationships Between Child Fussy Eating and Maternal Feeding Practices
Objective: Child fussy eating has been associated with a range of maternal feeding practices; however, whether effects are parent-driven, child-driven, or bidirectional (i.e., both) remains unclear. This study tested for bidirectional relationships between nonresponsive and structure-related maternal feeding practices and child fussy eating at age 2, 3.7, and 5 years using a cross-lagged model approach.
Methods: First-time Australian mothers (N = 207) reported four nonresponsive and four structure-related feeding practices and child food fussiness (FF) using validated questionnaires at child age 2, 3.7, and 5 years. Bivariate cross-lagged analyses were conducted for each of the eight feeding practices separately.
Results: Both child- and parent-driven associations were observed. Higher FF at 3.7 years predicted higher nonresponsive feeding practices and less structure-related practices at 5 years. Higher structure-related practices at 2 and 3.7 years predicted lower FF at 3.7 and 5 years, respectively. Use of food as a reward for behavior at 3.7 years predicted higher FF at 5 years.
Conclusions: Both parent- and child-driven associations explain the relationship between fussy eating and feeding practices. Given that early fussy eating is associated with more nonresponsive feeding, providing parents with anticipatory guidance to manage fussy eating behavior in infants and toddlers may help to avoid the use of these practices. Furthermore, the use of structure-related feeding practices and avoiding the use of food rewards may help to prevent the development of fussy eating
DNA Testing Reveals the Putative Identity of JB55, a 19th Century Vampire Buried in Griswold, Connecticut
In 1990 in Griswold, Connecticut, archaeologists excavated a burial found in a "skull and crossbones" orientation. The lid of the 19th century coffin had brass tacks that spelled "JB55", the initials of the person lying there and age at death. JB55 had evidence of chronic pulmonary infection, perhaps tuberculosis. It is possible that JB55 was deemed a vampire due to his disease, and therefore had to be "killed" by mutilating his corpse. In an attempt to reveal the identity of JB55, DNA testing was performed. Ancestry informative single nucleotide polymorphism (SNP) analysis using the Precision ID Ancestry Panel indicated European ancestry. A full Y-chromosomal short tandem repeat (Y-STR) profile was obtained, belonging to haplogroup R1b. When the Y-STR profile was searched in the publicly accessible FamilyTreeDNA R1b Project website, the two closest matches had the surname "Barber". A search of historical records led to a death notice mentioning John Barber, whose son Nathan Barber was buried in Griswold in 1826. The description of Nathan Barber closely fits the burial of "NB13," found near JB55. By applying modern forensic DNA tools to a historical mystery, the identity of JB55 as John Barber, the 19th century Connecticut vampire, has been revealed
The association of health literacy with adherence in older 2 adults, and its role in interventions: a systematic meta-review
Background: Low health literacy is a common problem among older adults. It is often suggested to be associated with poor adherence. This suggested association implies a need for effective adherence interventions in low health literate people. However, previous reviews show mixed results on the association between low health literacy and poor adherence. A systematic meta-review of systematic reviews was conducted to study the association between health literacy and adherence in adults above the age of 50. Evidence for the effectiveness of adherence interventions among adults in this older age group with low health literacy was also explored. Methods: Eight electronic databases (MEDLINE, ERIC, EMBASE, PsycINFO, CINAHL, DARE, the Cochrane Library, and Web of Knowledge) were searched using a variety of keywords regarding health literacy and adherence. Additionally, references of identified articles were checked. Systematic reviews were included if they assessed the association between health literacy and adherence or evaluated the effectiveness of interventions to improve adherence in adults with low health literacy. The AMSTAR tool was used to assess the quality of the included reviews. The selection procedure, data-extraction, and quality assessment were performed by two independent reviewers. Seventeen reviews were selected for inclusion. Results: Reviews varied widely in quality. Both reviews of high and low quality found only weak or mixed associations between health literacy and adherence among older adults. Reviews report on seven studies that assess the effectiveness of adherence interventions among low health literate older adults. The results suggest that some adherence interventions are effective for this group. The interventions described in the reviews focused mainly on education and on lowering the health literacy demands of adherence instructions. No conclusions could be drawn about which type of intervention could be most beneficial for this population. Conclusions: Evidence on the association between health literacy and adherence in older adults is relatively weak. Adherence interventions are potentially effective for the vulnerable population of older adults with low levels of health literacy, but the evidence on this topic is limited. Further research is needed on the association between health literacy and general health behavior, and on the effectiveness of interventions
How markets slowly digest changes in supply and demand
In this article we revisit the classic problem of tatonnement in price
formation from a microstructure point of view, reviewing a recent body of
theoretical and empirical work explaining how fluctuations in supply and demand
are slowly incorporated into prices. Because revealed market liquidity is
extremely low, large orders to buy or sell can only be traded incrementally,
over periods of time as long as months. As a result order flow is a highly
persistent long-memory process. Maintaining compatibility with market
efficiency has profound consequences on price formation, on the dynamics of
liquidity, and on the nature of impact. We review a body of theory that makes
detailed quantitative predictions about the volume and time dependence of
market impact, the bid-ask spread, order book dynamics, and volatility.
Comparisons to data yield some encouraging successes. This framework suggests a
novel interpretation of financial information, in which agents are at best only
weakly informed and all have a similar and extremely noisy impact on prices.
Most of the processed information appears to come from supply and demand
itself, rather than from external news. The ideas reviewed here are relevant to
market microstructure regulation, agent-based models, cost-optimal execution
strategies, and understanding market ecologies.Comment: 111 pages, 24 figure
Long-term burden of increased body mass index from childhood on adult dyslipidemia: the i3C Consortium study
Background: Data are limited regarding the association of cumulative burden and trajectory of body mass index (BMI) from early life with adult lipid disorders. Methods: The study cohort consisted of 5195 adults who had BMI repeatedly measured 4 to 21 times from childhood and had blood lipid measurements of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) and information on lipid-lowering medications in the last adult survey. The area under the curve (AUC) was calculated as a measure of long-term burden (total AUC) and trends (incremental AUC) of BMI. Results: Participants with dyslipidemia, high LDL-C, low HDL-C and high TG had consistently and significantly higher BMI levels from childhood to adulthood compared to those with normal lipid levels. After adjusting for age, race, sex, and cohort, increased risk of adult dyslipidemia was significantly associated with higher values of childhood BMI, adulthood BMI, total AUC and incremental AUC, with odds ratio (95% confidence interval) = 1.22 (1.15-1.29), 1.85 (1.74-1.97), 1.61 (1.52-1.71), and 1.59 (1.50-1.69), respectively, and p Conclusions: Adults with dyslipidemia versus normal lipid levels have consistently higher levels and distinct life-course trajectories of BMI, suggesting that the impact of excessive body weight on dyslipidemia originates in early life
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