5,353 research outputs found
Presence and task performance:an approach in the light of cognitive style
The paper highlights the relationship between each of four bi-polar dimensions of personality cognitive style, such as extraversion–introversion, sensing–intuition, thinking–feeling and judging–perceiving, and the level of sense of presence experienced. Findings indicate that individuals who are more sensitive, more feeling or more introverted experience a higher level of presence. While not reaching statistical significance, differing cognitive styles appear to impact on task performance. The apparent negative relationship discovered between sense of presence and task performance should be considered in the light of task characteristics. We discuss the implications of these findings and how they contribute to an understanding of the complex relationship that exists between presence and task performance and how this subsequently ought to influence the design of virtual environments
The transmission of nosocomial pathogens in an intensive care unit: a space–time clustering and structural equation modelling approach
We investigated the incidence of cases of nosocomial pathogens and risk factors in an intensive treatment unit ward to determine if the number of cases is dependent on location of patients and the colonization/infection history of the ward. A clustering approach method was developed to investigate the patterns of spread of cases through time for five microorganisms [methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter spp., Klebsiella spp., Candida spp., and Pseudomonas aeruginosa] using hospital microbiological monitoring data and ward records of patient-bed use. Cases of colonization/infection by MRSA, Candida and Pseudomonas were clustered in beds and through time while cases of Klebsiella and Acinetobacter were not. We used structural equation modelling to analyse interacting risk factors and the potential pathways of transmission in the ward. Prior nurse contact with colonized/infected patients, mediated by the number of patient-bed movements, were important predictors for all cases, except for those of Pseudomonas. General health and invasive surgery were significant predictors of cases of Candida and Klebsiella. We suggest that isolation and bed movement as a strategy to manage MRSA infections is likely to impact upon the incidence of cases of other opportunist pathogen
Methods to Isolate Possible Bacteriophage for Micrococcus Luteus and Acinetobacter Baumannii
The increasing prevalence of antibiotic-resistant strains of bacteria has led to a crisis in treatment options. Acinetobacter baumannii is an example of a bacterium that has developed a dangerous level of multidrug resistance. Not only does it have genes allowing for the resistance to antibiotics, but it also produces a biofilm that protects it. In recent years, A. baumannii has become a major contributor to nosocomial infections making it critical to develop new treatment methods. Micrococcus luteus, while typically not thought of as a pathogen, is also developing a resistance to antibiotics. M. luteus is capable of forming a biofilm on its own making it worrisome as it has increasingly been noted as an opportunistic pathogen.
One potential new treatment of antibiotic resistance is the development of bacteriophage therapy, using bacterial viruses to target the infection and treat it. This study examines methods for isolating novel bacteriophage from dairy cattle feces, specifically for the biofilm producers A. baumannii and M. luteus
Mitigation of Human Supervisory Control Wait Times through Automation Strategies
The application of network centric operations principles to human supervisory control
(HSC) domains means that humans are increasingly being asked to manage multiple
simultaneous HSC processes. However, increases in the number of available information
sources, volume of information and operational tempo, all which place higher
cognitive demands on operators, could become constraints limiting the success of network
centric processes. In time-pressured scenarios typical of networked command
and control scenarios, efficiently allocating attention between a set of dynamic tasks
is crucial for mission success. Inefficient attention allocation leads to system wait
times, which could eventually lead to critical events such as missed times on targets
and degraded overall mission success. One potential solution to mitigating wait times
is the introduction of automated decision support in order to relieve operator workload.
However, it is not obvious what automated decision support is appropriate, as
higher levels of automation may result in a situation awareness decrement and other
problems typically associated with excessive automation such as automation bias.
To assess the impact of increasing levels of automation on human and system performance
in a time-critical HSC multiple task management context, an experiment
was run in which an operator simultaneously managed four highly autonomous unmanned
aerial vehicles (UAVs) executing an air tasking order, with the overall goal
of destroying a pre-determined set of targets within a limited time period. Four increasing
levels automated decision support were investigated as well as high and low
operational replanning tempos. The highest level of automation, management-byexception,
had the best performance across several metrics but had a greater number
of catastrophic events during which a UAV erroneously destroyed a friendly target.
Contrary to expectations, the collaborative level of decision support, which provided
predictions for possible periods of task overload as well as possible courses of action
to relieve the high workload, produced the worst performance. This is attributable
to an unintended consequence of the automation where the graphical visualization of
the computer’s predictions caused users to try to globally optimize the schedules for
all UAVs instead of locally optimizing schedules in the immediate future, resulting in
them being overwhelmed. Total system wait time across both experimental factors
was dominated by wait time caused by lack of situation awareness, which is difficult
to eliminate, implying that there will be a clear upper limit on the number of vehicles
that any one person can supervise because of the need to stay cognitively aware of
unfolding events.Prepared for Boeing, Phantom Work
Parent-Child Relationships in Early Learning.
Parental behavior during a child’s first five years of life is critical for the development of important social and cognitive outcomes in children that set the stage for life-long adaptation and functioning. This chapter will review some of the key findings about the importance of parent-child relationships in early learning. Three dimensions of parent behavior will be described as “parental engagement”: (a) warmth and sensitivity, (b) support for a child’s emerging autonomy, and (c) active participation in learning. Cross cultural variations in which the styles of these behaviors are expressed are also considered, contrasting physical, social, and cognitive styles of communicating parental care
Immediate replacement of fishing with dairying by the earliest farmers of the NE Atlantic archipelagos
The appearance of farming, from its inception in the Near East around 12 000 years ago, finally reached the northwestern extremes of Europe by the fourth millennium BC or shortly thereafter. Various models have been invoked to explain the Neolithization of northern Europe; however, resolving these different scenarios has proved problematic due to poor faunal preservation and the lack of specificity achievable for commonly applied proxies. Here, we present new multi-proxy evidence, which qualitatively and quantitatively maps subsistence change in the northeast Atlantic archipelagos from the Late Mesolithic into the Neolithic and beyond. A model involving significant retention of hunter–gatherer–fisher influences was tested against one of the dominant adoptions of farming using a novel suite of lipid biomarkers, including dihydroxy fatty acids, ω-(o-alkylphenyl)alkanoic acids and stable carbon isotope signatures of individual fatty acids preserved in cooking vessels. These new findings, together with archaeozoological and human skeletal collagen bulk stable carbon isotope proxies, unequivocally confirm rejection of marine resources by early farmers coinciding with the adoption of intensive dairy farming. This pattern of Neolithization contrasts markedly to that occurring contemporaneously in the Baltic, suggesting that geographically distinct ecological and cultural influences dictated the evolution of subsistence practices at this critical phase of European prehistory
Prehospital ambulance 12-lead electrocardiograms reduce door to needle time for thrombolysis in the emergency room
Digitalitzat per Artypla
Do ultrafast exciton-polaron decoherence dynamics govern photocarrier generation efficiencies in polymer solar cells?
All-organic-based photovoltaic solar cells have attracted considerable
attention because of their low-cost processing and short energy payback time.
In such systems the primary dissociation of an optical excitation into a pair
of photocarriers has been recently shown to be extremely rapid and efficient,
but the physical reason for this remains unclear. Here, two-dimensional
photocurrent excitation spectroscopy, a novel non-linear optical spectroscopy,
is used to probe the ultrafast coherent decay of photoexcitations into
charge-producing states in a polymer:fullerene based solar cell. The
two-dimensional photocurrent spectra are interpreted by introducing a
theoretical model for the description of the coupling of the electronic states
of the system to an external environment and to the applied laser fields. The
experimental data show no cross-peaks in the two-dimensional photocurrent
spectra, as predicted by the model for coherence times between the exciton and
the photocurrent producing states of 20\,fs or less
- …