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This registration is for the project "Effects of Subthalamic Nucleus Deep Brain Stimulation on Cognition and Motor Function in subjects with Parkinson's disease". In this study, we are testing the effect of low and high-frequency deep brain stimulation of the subthalamic nucleus on cognitive and motor function in subjects with PD.

The strategic objective of this paper is to discuss how virtual Factory Acceptance Tests (FATs) will contribute towards achieving capital project excellence. The pandemic has transformed virtual FATs into an accepted method of testing which is likely to become a standard in the post-pandemic project execution. Virtual FATs are sustainable and smart alternative that reduces associated costs, time, resources and CO2 impact. This paper will highlight the advantages of assembling a global team and conducting a virtual FAT using an internet cloud service based on a combination of inhouse project experience and literature review. Virtual FAT supplements and produces equally dependable results as a traditional witnessed FAT. Virtual FAT opens up the experience to a wider global audience. This paper will provide cost comparisons between the two different types of FATs based on CAPEX and OPEX to establish economic advantages due to this switch. Despite travel restrictions due to pandemic, with virtual FAT project schedule can be met while reducing project risks, cost and CO2 impact. This paper will review the Modbus interface testing between different systems using IPSec VPN tunnel based on combination of inhouse project experience and literature review. With virtual FAT has created new ways of working by providing previously unseen benefits through the extended use of digital tools. Traditionally FATs involved several days of costly travel. With virtual FAT solution, project team can fully participate in FATs by receiving all the necessary information in real time and define improvements based on fully assembled test system without leaving their location. This paper will also emphasize virtual FAT benefits from operators’ perspective. The IPSec tunnel creates robust security layers to fully protect the data that is transmitted over the Internet. This paper will highlight how remote collaboration using augmented reality can be performed using Microsoft HoloLens and Microsoft Teams meeting. Limiting greenhouse gas emission is very critical to protect our environment. All energy producers endeavor to reduce the carbon footprint. This paper will highlight how emissions can be reduced by virtual FAT. In conclusion this paper will summarize how virtual FAT definitely has future potential beyond pandemic. This paper will present a case study on how virtual FAT can reduce the CAPEX, decrease FAT execution time with maintaining reliability and also minimize the carbon impact. Although remote monitoring is well proven, this paper will highlight how this concept can be extended to virtual remote testing of complex system and packages. This paper will emphasize how a well-planned virtual FAT can benefit all involved parties. From time and cost savings to accessibility and better documentation and reduced CO2 impact, a virtual FAT has many advantages and is now here to stay.

The rationale for the quest to close the left atrial appendage (LAA) for stroke prevention is composed of three elements: the concept that atrial fibrillation (AF) causes strokes, the concept that strokes are associated with thrombus formation in the LAA, and that these thrombi cause strokes by embolisation to the cerebral circulation. There are strong data supporting an association between AF and stroke. The Framingham study following 5,070 patients over 34 years demonstrated an approximately fivefold higher stroke risk in individuals with AF than in those without.1 Though this does not prove a causal relationship, it is important to mention that this risk remained even after adjustment for other risk factors such as hypertension, coronary artery disease, congestive heart failure, and age. Another element to support LAA closure is that there must be proof that thrombus formation occurs predominantly in the LAA. One would imagine that there are abundant data to support the concept that, in AF, thrombus formation occurs predominantly in the LAA; however, in almost all texts discussing the pathophysiology of stroke in AF there are few publications cited to support this concept. Blackshear et al included 1,288 patients with non-valvular AF who underwent either transoesophageal echocardiography (TOE) or autopsy. 2 Thrombus formation was reported in 222 patients, 91% of which was located in the LAA. It was further supported by a more comprehensive meta-analysis by Mahajan et al who demonstrated that 89% of thrombi in the left atrium (LA) were located in the LAA.3 This was corroborated by a study in the realm of degenerative aortic stenosis by Parashar et al.4 In this study, all left atrial thrombi resided in the LAA. It is worth mentioning that the LAA is the most common site of intracardiac thrombi not only in patients with AF but also in patients in sinus rhythm.5 More direct evidence is now available proving that a large proportion of strokes in AF are the result of thrombus in the LAA. The PROTECT AF and PREVAIL studies (described later in this document) provide evidence for the protective effect of LAA closure on thromboembolic events (Chapter 5), although some have debated the evidence (Chapter 6).6 In order to justify LAA closure it is important to show that, when thrombus occurs in the LAA, it can embolise in the cerebral circulation. o demonstrate this, a thrombus embolising to the brain would have to be caught in the act. Parekh et al describe real-time imaging capture of LAA thrombus embolisation during TOE with subsequent stroke after a delay of 4 hours of the witnessed embolisation, possibly due to initial retention at a non-occlusive location with subsequent fragmentation and delayed more distal embolisation.7 The fact that LAA closure prevents thromboembolic events as detailed above is also indirect proof for embolisation from LAA as a cause of embolic events.

There are very few data on the prognosis of possible versus definite infective endocarditis (IE). We studied data from 365 consecutive patients with IE involving native heart valve seen in an academic institution from 1990 to 2012. Patients were classified according to the modified Duke criteria for IE: patients with possible IE (n = 101, 28%) and those with definite IE (n = 264, 72%). Patients with possible IE were older than those with definite IE (66 ± 15 vs 62 ± 16, p = 0.05). A causative microorganism was identified in 66% of patients with possible IE versus all patients with definite IE (p0.0001) and only 41% had major echocardiographic criteria (vs 100%; p0.0001). Overall, 139 patients died over a mean ± SD follow-up of 3.9 ± 4.5 years (median 2.2, interquartile range 5.9 years). Patients with possible and definite IE had a similar risk of death. Independent predictors of long-term mortality were increasing age (hazard ratio [HR] 1.02, 95% confidence interval [CI] 1.01 to 1.04; p = 0.0009), vegetation length15 mm (HR 1.87, 95% CI 1.14 to 3.06; p = 0.01), and stroke (HR 4.10, 95% CI 1.84 to 9.17; p = 0.0006), whereas infection of mitral valve (HR 0.57, 95% CI 0.34 to 0.94; p = 0.03) and surgery (HR 0.43, 95% CI 0.19 to 0.99; p = 0.05) were associated with a better prognosis. Patients with definite IE and those with possible IE who did not undergo surgery had a worse prognosis than their counterparts with surgery. In conclusion, unselected patients with possible IE (Duke criteria) had a similar prognosis than those with definite IE.

Objectives: To study the usefulness of a novel echocardiographic technique, velocity vector imaging (VVI) in the measurement of left ventricular ejection fraction (LVEF). Background: Ejection fraction measured by echocardiography forms the cornerstone in the assessment of LV systolic function. Errors in measurement of EF by routine two-dimensional echocardiography (2D ECHO) limit its utility. The VVI is a new technology which uses speckle tracking and other algorithms to track the endocardial border. This may help in more accurate assessment of EF. Methods: Global and regional LVEF was measured in 49 patients using VVI, 2D ECHO and radionuclide-gated single photon emission computed tomography (SPECT). Results were categorised as normal, mild, moderate, or severe LV systolic dysfunction based on American Society of ECHO classification. The results were analysed by appropriate statistical tests for correlations. Results: The mean EF was 35 ± 12.08% by VVI, 54.2 ± 19.51% by SPECT (P< 0.001 vs VVI) and 50.3 ± 8.92% by 2D ECHO (P < 0.001 vs VVI). There was weak linear positive correlation between EF measured by VVI and the other modalities (Pearson's correlation coefficient 0.577 for SPECT and 0.573 for 2D; P=0.01). The VVI systematically underestimated the EF compared to SPECT. Greater number of patients had moderate or severe LV systolic dysfunction by VVI (37; 74.5%) than by SPECT (17; 34.7%; P=0.037). We derived a correction factor to calculate SPECT EF from VVI EF as follows: EF (SPECT) = EF (VVI) × 0.9 + 21 or approximately VVI (EF) + 20. Conclusion: Measurement of EF by VVI is feasible. The VVI underestimated the EF when compared to nuclear-gated SPECT in this study. The accuracy of this technology and the need for a correction factor needs to be assessed in future studies.