177 research outputs found
Flight test and evaluation of Omega navigation in a general aviation aircraft. Volume 2: Appendices
Detailed documentation for each flight of the Omega Flight Evaluation study is presented, including flight test description sheets and actual flight data plots. Computer programs used for data processing and flight planning are explained and the data formats utilized by the Custom Interface Unit are summarized
Seven unconfirmed ideas to improve future ICU practice
With imprecise definitions, inexact measurement tools, and flawed study execution, our clinical science often lags behind bedside experience and simply documents what appear to be the apparent faults or validity of ongoing practices. These impressions are later confirmed, modified, or overturned by the results of the next trial. On the other hand, insights that stem from the intuitions of experienced clinicians, scientists and educators-while often neglected-help place current thinking into proper perspective and occasionally point the way toward formulating novel hypotheses that direct future research. Both streams of information and opinion contribute to progress. In this paper we present a wide-ranging set of unproven 'out of the mainstream' ideas of our FCCM faculty, each with a defensible rationale and holding clear implications for altering bedside management. Each proposition was designed deliberately to be provocative so as to raise awareness, stimulate new thinking and initiate lively dialog.SCOPUS: re.jinfo:eu-repo/semantics/publishe
Metabolic and nutritional support of critically ill patients: consensus and controversies.
The results of recent large-scale clinical trials have led us to review our understanding of the metabolic response to stress and the most appropriate means of managing nutrition in critically ill patients. This review presents an update in this field, identifying and discussing a number of areas for which consensus has been reached and others where controversy remains and presenting areas for future research. We discuss optimal calorie and protein intake, the incidence and management of re-feeding syndrome, the role of gastric residual volume monitoring, the place of supplemental parenteral nutrition when enteral feeding is deemed insufficient, the role of indirect calorimetry, and potential indications for several pharmaconutrients
Ribonuclease 1 attenuates septic cardiomyopathy and cardiac apoptosis in a murine model of polymicrobial sepsis.
Septic cardiomyopathy is a life-threatening organ dysfunction caused by sepsis. Ribonuclease 1 (RNase 1) belongs to a group of host-defense peptides that specifically cleave extracellular RNA (eRNA). The activity of RNase1 is inhibited by ribonuclease-inhibitor 1 (RNH1). The role of RNase 1 in septic cardiomyopathy and associated cardiac apoptosis, however, is completely unknown. Here, we showed that sepsis resulted in a significant increase in RNH1 and eRNA serum levels compared to those of healthy subjects (p < 0.05). Treatment with RNase 1 resulted in a significant decrease of apoptosis, induced by the intrinsic pathway, and TNF expression in murine cardiomyocytes exposed to either necrotic cardiomyocytes or serum of septic patients for 16 h (p < 0.05). Furthermore, treatment of septic mice with RNase 1 resulted in a reduction in cardiac apoptosis, TNF expression and septic cardiomyopathy (p < 0.05). These data demonstrate that eRNA plays a crucial role in the pathophysiology of the organ (cardiac) dysfunction in sepsis and RNase and RNH1 may be new therapeutic targets/strategies to reduce the cardiac injury and dysfunction caused by sepsis
Experiments in vortex avalanches
Avalanche dynamics is found in many phenomena spanning from earthquakes to
the evolution of species. It can be also found in vortex matter when a type II
superconductor is externally driven, for example, by increasing the magnetic
field. Vortex avalanches associated with thermal instabilities can be an
undesirable effect for applications, but "dynamically driven" avalanches
emerging from the competition between intervortex interactions and quenched
disorder constitute an interesting scenario to test theoretical ideas related
with non-equilibrium dynamics. However, differently from the equilibrium phases
of vortex matter in type II superconductors, the study of the corresponding
dynamical phases - in which avalanches can play a role - is still in its
infancy. In this paper we critically review relevant experiments performed in
the last decade or so, emphasizing the ability of different experimental
techniques to establish the nature and statistical properties of the observed
avalanche behavior.Comment: To be published in Reviews of Modern Physics April 2004. 17 page
New generation indirect calorimeters for measuring energy expenditure in the critically ill: a rampant or reticent revolution?
The role of nutritional support in the physical and functional recovery of critically ill patients: a narrative review
Ectopic Expression of Neurogenin 2 Alone is Sufficient to Induce Differentiation of Embryonic Stem Cells into Mature Neurons
Recent studies show that combinations of defined key developmental transcription factors (TFs) can reprogram somatic cells to pluripotency or induce cell conversion of one somatic cell type to another. However, it is not clear if single genes can define a cell̀s identity and if the cell fate defining potential of TFs is also operative in pluripotent stem cells in vitro. Here, we show that ectopic expression of the neural TF Neurogenin2 (Ngn2) is sufficient to induce rapid and efficient differentiation of embryonic stem cells (ESCs) into mature glutamatergic neurons. Ngn2-induced neuronal differentiation did not require any additional external or internal factors and occurred even under pluripotency-promoting conditions. Differentiated cells displayed neuron-specific morphology, protein expression, and functional features, most importantly the generation of action potentials and contacts with hippocampal neurons. Gene expression analyses revealed that Ngn2-induced in vitro differentiation partially resembled neurogenesis in vivo, as it included specific activation of Ngn2 target genes and interaction partners. These findings demonstrate that a single gene is sufficient to determine cell fate decisions of uncommitted stem cells thus giving insights into the role of key developmental genes during lineage commitment. Furthermore, we present a promising tool to improve directed differentiation strategies for applications in both stem cell research and regenerative medicine
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