Adverse effects of infusion therapy in anesthesia and intensive care

In this thesis we investigated adverse events following transfusion and infusion therapy during anesthesia and intensive care. We focussed on a selection of different aspects in patients in the operation room, intensive care and on the ward. First, we sought to provide insights for which patients the risk of a common transfusion complication, transfusion-associated circulatory overload (TACO), outweighs the potential benefit of a transfusion. Second, we explored possible mechanisms underlying the development of TACO. Third, we searched for ways to optimize infusion therapy in the perioperative period. Our research suggests alternative mechanisms than just hydrostatic pressure overload for the development of TACO. Risk factors for TACO in comparison to patients developing circulatory overload without receiving transfusion products, COP of transfusion products, and clinical research on the effect of transfusion on hydrostatic pressure support a different pathogenesis. Our data helped put together one part of the puzzle. Future studies on TACO pathogenesis should focus on the effect of transfusion products on the endothelial barrier, and how an inflammatory process is part of this effect. Furthermore, we aimed to optimize perioperative infusion therapy. We showed a restrictive infusion regimen is associated with a reduction in complications. We developed a novel method of non-invasive CO monitoring derived from CCA flow. However, this method is not accurate and not precise

Path Puzzles: Discrete Tomography with a Path Constraint is Hard

We prove that path puzzles with complete row and column information--or equivalently, 2D orthogonal discrete tomography with Hamiltonicity constraint--are strongly NP-complete, ASP-complete, and #P-complete. Along the way, we newly establish ASP-completeness and #P-completeness for 3-Dimensional Matching and Numerical 3-Dimensional Matching.Comment: 16 pages, 8 figures. Revised proof of Theorem 2.4. 2-page abstract appeared in Abstracts from the 20th Japan Conference on Discrete and Computational Geometry, Graphs, and Games (JCDCGGG 2017

Cognitive dysfunction and dementia in Parkinson's disease

Parkinson's disease (PD) is a slowly progressive neurodegenerative disorder mainly characterized by degeneration of dopaminergic neurons in the substantia nigra and the ventral tegmental area, in combination with a varying loss of central noradrenergic (locus coeruleus), cholinergic (nucleus basalis of Meynert) and serotonergic (dorsal raphe nuclei) integrity, leading to a multitude of motor and non-motor behavioral disturbances. Apart from the clinical motor hallmarks, in the early stages of disease, subtle cognitive dysfunction might be seen comprising mainly executive dysfunction, with secondary visuospatial and mnemonic disturbances. In about 20-40% of patients, these problems may eventually proceed to dementia, which constitutes an important risk factor for caregiver distress, decreased quality of life and nursing home placement. Dementia in PD is typically characterized by a progressive dysexecutive syndrome with attentional deficits and fluctuating cognition, often accompanied by psychotic symptoms. It is thought to be the result of a combination of both subcortical and cortical changes. PD-related dopaminergic deficiency in the nucleus caudatus and mesocortical areas (due to degeneration of projections from the substantia nigra and ventral tegmental area) and cholinergic deficiency in the cortex (due to degeneration of ascending projections from the nucleus basalis of Meynert), combined with additional Alzheimer-pathology and cortical Lewy bodies, may greatly contribute to dementia. Current treatment of dementia in PD is based on compensation of the profound cholinergic deficiency. Recent studies with the cholinesterase inhibitors galantamine, donepezil and rivastigmine show promising results in improving cognition and ameliorating psychotic symptoms, which must further be confirmed in randomized controlled trials

A metriplectic formulation of polarized radiative transfer

We present a metriplectic formulation of the radiative transfer equation with polarization and varying refractive index and show that this formulation automatically satisfies the first two laws of thermodynamics. In particular, the derived antisymmetric bracket enjoys the Jacobi identity. To obtain this formulation we suitably transform the equation and show that important physical quantities derived from the solution remain invariant under such a transformation

Computational Complexity of Generalized Push Fight

We analyze the computational complexity of optimally playing the two-player board game Push Fight, generalized to an arbitrary board and number of pieces. We prove that the game is PSPACE-hard to decide who will win from a given position, even for simple (almost rectangular) hole-free boards. We also analyze the mate-in-1 problem: can the player win in a single turn? One turn in Push Fight consists of up to two "moves" followed by a mandatory "push". With these rules, or generalizing the number of allowed moves to any constant, we show mate-in-1 can be solved in polynomial time. If, however, the number of moves per turn is part of the input, the problem becomes NP-complete. On the other hand, without any limit on the number of moves per turn, the problem becomes polynomially solvable again