Search results for "Change over time"

Local field potential activity dynamics in response to deep brain stimulation of the subthalamic nucleus in Parkinson's disease

2020

Abstract Local field potentials (LFPs) may afford insight into the mechanisms of action of deep brain stimulation (DBS) and potential feedback signals for adaptive DBS. In Parkinson's disease (PD) DBS of the subthalamic nucleus (STN) suppresses spontaneous activity in the beta band and drives evoked resonant neural activity (ERNA). Here, we investigate how STN LFP activities change over time following the onset and offset of DBS. To this end we recorded LFPs from the STN in 14 PD patients during long (mean: 181.2 s) and short (14.2 s) blocks of continuous stimulation at 130 Hz. LFP activities were evaluated in the temporal and spectral domains. During long stimulation blocks, the frequency …

Return and Disclosure of Research Results: Parental Attitudes and Needs Over Time in Pediatric Oncology.

2017

Objectives To explore parental attitudes regarding the return and disclosure of research findings in pediatric cancer trials over time. Study design Two surveys were set up to evaluate the stability of parental attitudes. One survey was carried out among 581 parents whose child was diagnosed recently (response rate, 53.5%). A second, population-based survey was set up with a time interval of 4 years between first cancer diagnosis and survey in which 1465 parents were included (response rate, 55.1%). Results Almost all surveyed parents stated a parental right to receive aggregate research results. Fifty-five percent of the parents who recently participated in trials and 62% of those asked af…

The Randomized Shortened Dental Arch Study

2012

The scientific evidence concerning prosthodontic care for the shortened dental arch (SDA) is sparse. This randomized multicenter study aimed to compare two common treatment options: removable partial dental prostheses (RPDPs) for molar replacement vs. no replacement (SDA). One of the hypotheses was that the follow-up treatment differs between patients with RPDPs and patients with SDAs during the 5-year follow-up period. Two hundred and fifteen patients with complete molar loss in one jaw were included in the study. Molars were either replaced by RPDPs or not replaced according to the SDA concept. A mean number of 4.2 (RPDP) and 2.8 (SDA) treatments for biological or technical reasons occur…

Longitudinal study of alexithymia and multiple sclerosis

2013

Objective The aim of this study was to investigate the course of alexithymia and its relation with anxiety and depression in patients with multiple sclerosis (MS), over a period of 5 years. Methods Sixty-two MS patients were examined at two timepoints, 5 years apart, and they answered questionnaires collecting socio-demographic, medical, and psychological data (depression, anxiety, alexithymia). Results Our data show that emotional disorders remain stable over time in patients with MS, particularly as regards alexithymia and anxiety. Conversely, the rate of depression decreased between the two evaluations, falling from 40% to 26%. The two dimensions of alexithymia (i.e., difficulty describi…

Clustering of Lifestyle Risk Factors in Acute Coronary Syndrome: Prevalence and Change after the First Event

2018

Background: Healthy lifestyles are modifiable risk factors for acute coronary syndrome (ACS) onset and recurrence. While unhealthy lifestyles tend to cluster together within the general healthy population, little is known about the prevalence and clustering of these behaviours in people with ACS before and after the first acute event. The aim of this study was to identify lifestyle profiles of patients with ACS and to explore their change after their first coronary event. Methods: Three hundred and fifty-six patients completed self-report measures of healthy habits at the beginning of cardiac rehabilitation and 6 months later. By adopting a person-oriented approach, we analysed lifestyle cl…

Immediate and long-term microshear bond strength of resin-based cements to core build-up materials

2021

Background To evaluate the microshear bond strength (μ-SBS) between resin-based cements and core build-up materials after water storage. Material and methods Cylinders (1x1 mm) of conventional dual-cure resin cement (RelyX ARC, 3M ESPE), universal dual-cure resin cement (RelyX Ultimate, 3M ESPE) or self-adhesive resin cement (RelyX U200, 3M ESPE) were adhered to disks (6x2 mm) made with commercial core build-up materials (Bis-Core, Bisco or LuxaCore Z, DMG) or conventional nanocomposite resin (Filtek Z350 XT, 3M ESPE). The specimens (n=10) were submitted to μ-SBS test using a universal testing machine and fracture pattern analysis at 48 hours or after 9 months of water storage. The data wer…

2019

Abstract Background In old age, decline in functioning may cause changes in walking ability. Our aim was to study whether older people who report adaptive, maladaptive, or no walking modifications differ in outdoor mobility. Methods Community-dwelling people aged 75–90 years (N = 848) were interviewed at baseline, of whom 761 participated in the 2-year follow-up. Walking modifications were assessed by asking the participants whether they had modified their way of walking 2 km due to their health. Based on the responses, three categories were formed: no walking modifications (reference), adaptive (eg, walking more slowly, using an aid), and maladaptive walking modifications (reduced frequenc…

Effectiveness of local feature selection in ensemble learning for prediction of antimicrobial resistance

2008

In the real world concepts are often not stable but change over time. A typical example of this in the biomedical context is antibiotic resistance, where pathogen sensitivity may change over time as pathogen strains develop resistance to antibiotics that were previously effective. This problem, known as concept drift (CD), complicates the task of learning a robust model. Different ensemble learning (EL) approaches (that instead of learning a single classifier try to learn and maintain a set of classifiers over time) have been shown to perform reasonably well in the presence of concept drift. In this paper we study how much local feature selection (FS) can improve ensemble performance for da…

Is there an environmental Kuznets curve for Spain? Fresh evidence from old data

2012

Abstract The information content of the environmental Kuznets curve (EKC) is subject to change over time and all the empirical modeling work that does not take into account the possible variations and instabilities may fail to explain the variations in the per-capita CO2 and per-capita income relationship. In this paper we consider the possibility that a linear cointegrated regression model with multiple structural changes would provide a better empirical description of the Spanish EKC during the period 1857–2007. Our methodology is based on instability tests recently proposed in Kejriwal and Perron (2008, 2010) as well as on cointegration tests developed in Arai and Kurozumi (2007) and Kej…

Aggregate Behavior and Microdata

2004

Abstract It is shown how one can effectively use microdata in modelling the change over time in an aggregate (e.g. mean consumption expenditure) of a large and heterogeneous population. The starting point of our aggregation analysis is a specification of explanatory variables on the micro-level. Typically, some of these explanatory variables are observable and others are unobservable. Based on certain hypotheses on the evolution over time of the joint distributions across the population of these explanatory variables we derive a decomposition of the change in the aggregate which allows a partial analysis: to isolate and to quantify the effect of a change in the observable explanatory variab…