800 research outputs found
When the reaper becomes a salesman: The influence of terror management on product preferences
The present research investigates how consumer choice is affected by Terror Management Theory’s proposition of Mortality Salience increasing one’s cultural worldview defense and self-esteem striving. The study builds empirically upon prior theorizing by Arndt, Solomon, Kasser and Sheldon (2004). During an experiment, we manipulated Mortality Salience and measured product preferences for conspicuousness and familiarity. Participants primed with death were more likely to choose conspicuous products, corroborating previous research of mortality salience raising materialistic tendencies. In addition, participants showed a tendency to prefer familiar brands. These results are in line with the Terror Management Theory framework
Optimizing the performance of thermionic devices using energy filtering
Conventional thermionic power generators and refrigerators utilize a barrier
in the direction of transport to selectively transmit high-energy electrons.
Here we show that the energy spectrum of electrons transmitted in this way is
not optimal, and we derive the ideal energy spectrum for operation in the
maximum power regime. By using suitable energy filters, such as resonances in
quantum dots, the power of thermionic devices can, in principle, be improved by
an order of magnitude.Comment: 3 pages, 2 figure
La experiencia de la Comunidad Europea en cooperación para la educación superior
Se describen tres aspectos de las perspectivas de la Comunidad Europea para la internacionalización de la educación superior: la intracomunidad, la cooperación con paÃses vecinos y la cooperación con otras regiones del mundo como Canadá y Estados Unidos. La cooperación para la educación desempeña un papel clave en el reforzamiento tanto social como económico de la Comunidad, forjando un sentido de ciudadanÃa europea e incrementando el entendimiento de lo social, cultural y económico. Se incluye obra visual de Antonio RamÃrez, reproducida en blanco y negro.ITESO, A.C
Thermoelectric efficiency at maximum power in a quantum dot
We identify the operational conditions for maximum power of a
nanothermoelectric engine consisting of a single quantum level embedded between
two leads at different temperatures and chemical potentials. The corresponding
thermodynamic efficiency agrees with the Curzon-Ahlborn expression up to
quadratic terms in the gradients, supporting the thesis of universality beyond
linear response.Comment: 4 pages, 3 figure
How people with dementia use twitter: A qualitative analysis
People with dementia are publicly sharing their experiences of living with the condition and acting collectively to produce social change. Social media could support them in doing this, but no previous studies have comprehensively analysed their use of Twitter. The aims of this study were to identify how people with dementia use Twitter and examine the illness identities they create and promote online. Tweetcatcher was used to collect 2774 tweets posted over six months by 12 account holders with dementia, across three countries. Tweets were analysed thematically. Six themes were identified through the analysis: nothing about us without us, collective action, experts by experience, living with dementia not suffering from it, community, and stories of dementia. On Twitter, people with dementia are developing a collective illness identity to further a social movement that is focused on improving the lives of people with dementia. They are also communicating their personal identities by documenting their lived experiences. Twitter is being used to convey positive, rather than negative, messages about dementia. The findings of this study also show that thematic analysis can be applied to micro texts that can combine over time to form longer narratives
Measuring labor input on pasture-based dairy farms using a smartphone
peer-reviewedWith the cessation of milk quotas in the European Union, dairy herd sizes increased in some countries, including Ireland, with an associated increase in labor requirement. Second to feed costs, labor has been identified as one of the highest costs on pasture-based dairy farms. Compared with other European Union countries, Ireland has historically had low milk production per labor unit; thus, optimization of labor efficiency on farm should be addressed before or concurrently with herd expansion. The objective of this study was to quantify current levels of labor input and labor efficiency on commercial pasture-based dairy farms and to identify the facilities and management practices associated with increased labor efficiency. Thirty-eight dairy farms of varying herd sizes, previously identified as labor-efficient farms, were enrolled on the study and data were collected over 3 consecutive days each month over a 12-mo period, starting in May 2015 and finishing in August of 2016. This was achieved through the use of a smartphone application. For analysis purposes, farms were categorized into 1 of 3 herd size categories (HSC): farms with <150 cows (HSC 1), 150–249 cows (HSC 2), or ≥250 cows (HSC 3). Overall farm labor input increased with HSC with 3,015, 4,499, and 6,023 h worked on HSC 1, 2, and 3, respectively. A higher proportion of work was carried out by hired staff as herd size increased. Labor efficiency was measured as total hours input to the dairy enterprise divided by herd size. Labor efficiency improved as herd size increased above 250 cows with 17.3 h/cow per yr observed for HSC 3; labor efficiency was similar for HSC 1 and 2, at 23.8 and 23.3 h/cow per yr, respectively. A large range of efficiency was observed within HSC. The labor requirements had a distinct seasonal pattern across the 3 HSC with the highest input observed in springtime (February to April) primarily due to calving and calf-care duties, milking, and winter feeding. The lowest input was observed in wintertime (November to January) when cows were dry. Particular facilities and management practices were associated with efficiency within certain tasks, the most notable in regard to milking and winter feeding practices. Additionally, the most efficient farms used contractors to perform a higher proportion of machinery work on farm than the least efficient farms
Epigenetic regulatory pathways involving microRNAs may modulate the host immune response following major trauma
BACKGROUND
Posttraumatic nosocomial pneumonia is a common complication resulting in significant morbidity. Trauma-induced immunocompromise is associated with an enhanced susceptibility to pneumonia. In this study, we explore the hypothesis that posttranscriptional epigenetic regulation of gene expression may be an important factor in determining this immune phenotype. We describe the pattern of production of microRNAss (miRs) and their association with nosocomial pneumonia following severe trauma.
METHODS
A convenience sample of 30 ventilated polytrauma patients (UKCRN ID: 5637) and 16 healthy controls were recruited. Messenger RNA and protein levels of key cytokines were quantified within 2 hours of the injury and at 24 hours. Three miRs per cytokine were then selected based on miRBase target prediction scores and quantified using polymerase chain reaction. Nosocomial pneumonia was defined using the Centers for Disease Control and Prevention definitions.
RESULTS
Median Injury Severity Score (ISS) was 29, and 47% of the patients developed nosocomial pneumonia. miR-125a and miR-202 decreased by 34% and 77%, respectively, immediately following injury, whereas their target, IL-10, increased messenger RNA levels 3-fold and protein levels 180 fold. Tumor necrosis factor α (TNF-α) and IL-12 gene expression decreased by 68% and 43%, respectively, following injury, and this was mirrored by a 10-fold increase in miR-181, an miR predicted to target TNF-α transcripts. Lower levels of miR-125a and miR-374b were associated with the later acquisition of hospital-acquired pneumonia.
CONCLUSION
Alteration in the expression of miRs with highly predicted complementarity to IL-10 and TNF-α may be an important mechanism regulating the posttraumatic immunosuppressive phenotype in intensive care unit patients.
LEVEL OF EVIDENCE
Retrospective observational study, level III
A study of anodic films on n-InP by spectroscopic ellipsometry and atomic force microscopy
The growth of anodic films on n-InP in 1 mol dm-1 KOH is investigated under potential sweep conditions. At lower potentials a thin surface film is formed and a peak is observed on the current-voltage curve. Ellipsometric
measurements show that this film increases in thickness with increasing potential but the observed thickness values are significantly less than the corresponding coulometrically estimated values. This indicates that much of the charge passed is not involved in the formation of a surface film but
presumably in the formation of soluble anodic reaction products. Cyclic voltammograms show that a current peak is also observed on the reverse sweep and ellipsometric measurements show that the anodic film thickness
also increases during the reverse sweep until the peak potential is reached. Atomic force microscopy (AFM) shows that the surface becomes smoother as the potential is increased. We attribute this to the formation of nuclei at
lower potentials, which coalesce as the layer becomes thicker. Electron diffraction and x-ray photoelectron spectroscopy (XPS) analysis show that the surface film is predominantly In2O3 with no evidence of InPO4
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