21 research outputs found
Moving from talk to action: Implementing austerity-driven change
No full textOrganizational change is often proposed as a solution to austerity. Implementing change when there is no budget, however, is difficult. This paper explains how a major Dutch city implemented radical changes in the wake of the global financial crisis. The paper relates the change programme to eight accepted determinants of successful change. Drawing on the experience of 65 employees, the author explores three catalysts for success, which he calls ‘acts of implementation’. The paper explains why successful implementation of austerity-driven change is not just a matter of complying with eight static success conditions but also of crafting dynamic acts that fits the specific context of austerity. Implementers have to deal with politics, resistance and ambiguity to move from talk to action
Fabrieksvoorontwerp reactieve penextractie
No full textDocument(en) uit de collectie Chemische Procestechnologie.DelftChemTechApplied Science
Fashion, fads and the popularity of choices: Micro-foundations for diffusion consumer theory
No full textThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordKnowledge acquisition by consumers is a key process in the diffusion of innovations. However, in standard theories of the representative agent, agents do not learn and innovations are adopted instantaneously. Here, we show that in a discrete choice model where utility-maximising agents with heterogenous preferences learn about products through peers, their stock of knowledge on products becomes heterogenous, fads and fashions arise, and transitivity in aggregate preferences is lost. Non-equilibrium path-dependent dynamics emerge, the representative agent exhibits behavioural rules different than individual agents, and aggregate utility cannot be optimised. Instead, an evolutionary theory of product innovation and diffusion emerges.Engineering and Physical Sciences Research Council (EPSRC)Economic and Social Research Council (ESRC
The elimination of complications in hypospadias surgery:a training in analytical thought or a mission impossible?
No full textThis is a critical review of 376 patients with hypospadias that were treated by the first author. The techniques used were a one-stage procedure for the correction of hypospadias without chordee (type I) and a two-stage procedure for hypospadias with chordee (type II). Development of these techniques was based on several conjectures: (a) A curvature of the penis can be caused by skin shortage alone; (b) persistent chordee is due to inadequate release of the corpora or to inadequate resurfacing of the corporal defect; and (c) fistulas can be caused by devascularisation of skin, by tension on the suture line, by superposition of skin wound and urethra, by infection, by perforation of skin, and by the evacuation of urine causing a separation of the wound edges. These conjectures were tested over a period of 30 years by a combination of measures involving: (a) The rotation in one or two stages of well-vascularised dorsal skin, using a backcut; (b) the omission of transcutaneous sutures and dressing; and (c) the diversion of urine through drainage incisions or fenestrated stent. These measures resulted in a dramatic reduction of the number of patients in need of a type II procedure. Persistent chordee, although rare, could always be corrected before a definitive urethroplasty was performed. Fistulas were almost completely eliminated.</p
The elimination of complications in hypospadias surgery: a training in analytical thought or a mission impossible?
No full textThis is a critical review of 376 patients with hypospadias that were treated by the first author. The techniques used were a one-stage procedure for the correction of hypospadias without chordee (type I) and a two-stage procedure for hypospadias with chordee (type II). Development of these techniques was based on several conjectures: (a) A curvature of the penis can be caused by skin shortage alone; (b) persistent chordee is due to inadequate release of the corpora or to inadequate resurfacing of the corporal defect; and (c) fistulas can be caused by devascularisation of skin, by tension on the suture line, by superposition of skin wound and urethra, by infection, by perforation of skin, and by the evacuation of urine causing a separation of the wound edges. These conjectures were tested over a period of 30 years by a combination of measures involving: (a) The rotation in one or two stages of well-vascularised dorsal skin, using a backcut; (b) the omission of transcutaneous sutures and dressing; and (c) the diversion of urine through drainage incisions or fenestrated stent. These measures resulted in a dramatic reduction of the number of patients in need of a type II procedure. Persistent chordee, although rare, could always be corrected before a definitive urethroplasty was performed. Fistulas were almost completely eliminated
Translaminar Cortical Membrane Potential Synchrony in Behaving Mice
No full textSummaryThe synchronized activity of six layers of cortical neurons is critical for sensory perception and the control of voluntary behavior, but little is known about the synaptic mechanisms of cortical synchrony across layers in behaving animals. We made single and dual whole-cell recordings from the primary somatosensory forepaw cortex in awake mice and show that L2/3 and L5 excitatory neurons have layer-specific intrinsic properties and membrane potential dynamics that shape laminar-specific firing rates and subthreshold synchrony. First, while sensory and movement-evoked synaptic input was tightly correlated across layers, spontaneous action potentials and slow spontaneous subthreshold fluctuations had laminar-specific timing; second, longer duration forepaw movement was associated with a decorrelation of subthreshold activity; third, spontaneous and sensory-evoked forepaw movements were signaled more strongly by L5 than L2/3 neurons. Together, our data suggest that the degree of translaminar synchrony is dependent upon the origin (sensory, spontaneous, and movement) of the synaptic input
Moving from talk to action: Implementing austerity-driven change
No full textOrganizational change is often proposed as a solution to austerity. Implementing change when there is no budget, however, is difficult. This paper explains how a major Dutch city implemented radical changes in the wake of the global financial crisis. The paper relates the change programme to eight accepted determinants of successful change. Drawing on the experience of 65 employees, the author explores three catalysts for success, which he calls ‘acts of implementation’. The paper explains why successful implementation of austerity-driven change is not just a matter of complying with eight static success conditions but also of crafting dynamic acts that fits the specific context of austerity. Implementers have to deal with politics, resistance and ambiguity to move from talk to action
Predictive value of functional MRI and EEG in epilepsy diagnosis after a first seizure
No full textIt is often difficult to predict seizure recurrence in subjects who have suffered a first-ever epileptic seizure. In this study, the predictive value of physiological signals measured using Electroencephalography (EEG) and functional MRI (fMRI) is assessed. In particular those patients developing epilepsy (i.e. a second unprovoked seizure) that were initially evaluated as having a low risk of seizure recurrence are of interest.In total, 26 epilepsy patients, of which 8 were initially evaluated as having a low risk of seizure recurrence (i.e. converters), and 17 subjects with only a single seizure were included. All subjects underwent routine EEG as well as fMRI measurements. For diagnostic classification, features related to the temporal dynamics were determined for both the processed EEG and fMRI data. Subsequently, a logistic regression classifier was trained on epilepsy and first-seizure subjects. The trained model was tested using the clinically relevant converters group.The sensitivity, specificity, and AUC (mean +/- SD) of the regression model including metrics from both modalities were 74 +/- 19%, 82 +/- 18%, and 0.75 +/- 0.12, respectively. Positive and negative predictive values (mean SD) of the regression model with both EEG and fMRI features are 84 +/- 14% and 78 +/- 12%. Moreover, this EEG/fMRI model showed significant improvements compared to the clinical diagnosis, whereas the models using metrics from either EEG or fMRI do not reach significance (p > 0.05).Temporal metrics computationally derived from EEG and fMRI time signals may clinically aid and synergistically improve the predictive value in a first-seizure sample. (C) 2020 The Author(s). Published by Elsevier Inc
Associations of increased interstitial fluid with vascular and neurodegenerative abnormalities in a memory clinic sample
No full textThe vascular and neurodegenerative processes related to clinical dementia cause cell loss which induces, amongst others, an increase in interstitial fluid (ISF).We assessed microvascular, parenchymal integrity, and a proxy of ISF volume alterations with intravoxel incoherent motion imaging in 21 healthy controls and 53 memory clinic patients - mainly affected by neurodegeneration (mild cognitive impairment, Alzheimer's disease dementia), vascular pathology (vascular cognitive impairment), and presumed to be without significant pathology (subjective cognitive decline).The microstructural components were quantified with spectral analysis using a non-negative least squares method. Linear regression was employed to investigate associations of these components with hippocampal and white matter hyperintensity (WMH) volumes. In the normal appearing white matter, a large f(int )(a proxy of ISF volume) was associated with a large WMH volume and low hippocampal volume. Likewise, a large f(int) value was associated with a lower hippocampal volume in the hippocampi.Large ISF volume (f(int)) was shown to be a prominent factor associated with both WMHs and neurodegenerative abnormalities in memory clinic patients and is argued to play a potential role in impaired glymphatic functioning. (C) 2021 The Author(s). Published by Elsevier Inc
Assessment of microvascular rarefaction in human brain disorders using physiological magnetic resonance imaging
No full textCerebral microvascular rarefaction, the reduction in number of functional or structural small blood vessels in the brain, is thought to play an important role in the early stages of microvascular related brain disorders. A better understanding of its underlying pathophysiological mechanisms, and methods to measure microvascular density in the human brain are needed to develop biomarkers for early diagnosis and to identify targets for disease modifying treatments. Therefore, we provide an overview of the assumed main pathophysiological processes underlying cerebral microvascular rarefaction and the evidence for rarefaction in several microvascular related brain disorders. A number of advanced physiological MRI techniques can be used to measure the pathological alterations associated with microvascular rarefaction. Although more research is needed to explore and validate these MRI techniques in microvascular rarefaction in brain disorders, they provide a set of promising future tools to assess various features relevant for rarefaction, such as cerebral blood flow and volume, vessel density and radius and blood-brain barrier leakage.sponsorship: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the European Union's Horizon 2020 project 'CRUCIAL' (grant number 848109). (European Union's Horizon 2020 project 'CRUCIAL'|848109)status: Publishe
