1,720,996 research outputs found
Biomarkers in biological fluids for dementia with Lewy bodies
No full textDementia with Lewy bodies (DLB) has become the second most common neurodegenerative dementia due to demographic ageing. Differential diagnosis is still troublesome especially in early stages of the disease, since there is a great clinical and neuropathological overlap primarily with Alzheimer's disease and Parkinson's disease. Therefore, more specific biomarkers, not only for scientific reasons but also for clinical therapeutic decision-making, are urgently needed. In this review, we summarize the knowledge on fluid biomarkers for DLB, derived predominantly from cerebrospinal fluid. We discuss the value of well-defined markers (beta-amyloid, (phosphorylated) tau, alpha-synuclein) as well as some promising 'upcoming' substances, which still have to be further evaluated
About the influence of optimized light intensity distributions on visibility at low illumination levels in road lighting
No full textSeit der Einführung der Straßenbeleuchtung besteht ein Zielkonflikt zwischen dem Bestreben geringer Anlagenbetriebskosten und der Forderung nach angemessen hoher Beleuchtungsqualität zur Wahrung der Verkehrssicherheit. Mit den steigenden Energiekosten nimmt der Druck, Beleuchtungsanlagen auf ein Mindestbeleuchtungsniveau hin zu dimensionieren, weiter zu. Aus lichttechnischer Sicht kann dieser Konflikt durch eine optimal dimensionierte Verteilung des Lichts auf die Verkehrsfläche entschärft werden. Allerdings orientieren sich die Qualitätsvorgaben bestehender Planungs- und Bewertungsansätze an den lichttechnischen Möglichkeiten vergleichsweise inflexibler konventioneller Beleuchtungstechnologien. Anhand der Erkennbarkeit einfacher Sehobjekte auf der Fahrbahn klärt die Arbeit auf, welche Sicherheit diese Ansätze bereitstellen, wenn sie mittels optimierter Lichtstärkeverteilungskörper (LVK) bestmöglich erfüllt werden und identifiziert mögliche Verbesserungspotentiale. Die etablierten Optimierungsansätze Beleuchtungsstärke, Leuchtdichte und Visibility Level (VL) bilden dafür den Untersuchungsschwerpunkt. Installationsspezifisch erzeugte LVK werden im Rahmen der Untersuchungen so optimiert, dass sie für ein festgelegtes Beleuchtungsniveau eine größtmögliche Gesamtgleichmäßigkeit oder ein Mindestniveau an Erkennbarkeit bereitstellen. Gleichzeitig wird der benötigte Gesamtlichtstrom so gering wie möglich gehalten, um so unnötig hohen Energiebedarf zu vermeiden. Die vergleichende Bewertung der bereitgestellten Erkennbarkeit erfolgt mittels des VL und unter Verwendung flacher Sehobjekte unterschiedlichen Reflexionsgrades. Simulationen und exemplarische Nachstellungen von Beleuchtungsszenen decken Zusammenhänge zwischen den Bewertungsansätzen auf. So präzisiert die Arbeit den Gültigkeitsbereich vorangegangener Forschung zu den betrachteten Methoden und liefert neue Erkenntnisse für deren zielgerichtete Anwendbarkeit. Ein einzelner Ansatz, welcher für alle Beleuchtungssituationen die besten Sichtbedingungen bereitstellt, erwies sich dabei nicht als nachweisbar. Denn, wie die Arbeit zeigt, ist die bisher angestrebte hohe Gleichmäßigkeit bei adäquatem Beleuchtungsniveau allein kein Garant für gute Erkennbarkeit. Stattdessen ist situationsspezifisch oft eine Kombination aus Leuchtdichteniveau, Leuchtdichtegleichmäßigkeit und VL optimal. Die Resultate werden in einem Katalog fundierter Empfehlungen, unter welchen Bedingungen sich die verschiedenen Ansätze vorteilhaft anwenden lassen, zusammengefasst. Installationsbedingte Einflüsse, wie der Einfluss der Straßendeckschicht auf die Optimierungen oder die Auswirkungen der Vergrößerung des Lichtpunktabstandes im Verhältnis zur Lichtpunkthöhe runden werden ebenfalls diskutiert.Since the introduction of street lighting, there has been a trade-off between the desire to lower operating costs and the demand for appropriate lighting quality to maintain road safety. Ever-increasing energy costs demand the dimensioning of lighting systems limited to a minimum luminance or illuminance level. From a technical perspective, this conflict can be mitigated by an optimally matched distribution of light on the road surface. However, the requirements of existing planning and evaluation approaches are still based on comparatively inflexible conventional lighting technologies. Using flat targets visibility on the road this work clarifies, which level of security is provided by existing quality criteria when optimized using luminous intensity distributions (LID). The most common optimization approaches, illuminance, luminance, and visibility level (VL), are in the main focus of this study. Installation-specific LID are optimized to provide maximum luminance/illuminance uniformity or a minimum visibility level for a given average luminance/illuminance. At the same time the total luminous flux is kept to a minimum in order to avoid unnecessary energy usage. The comparative assessment of small object detecion is evaluated calulating the VL of flat targets of different reflectances. Using simulations and exemplary reproduction of lighting scenes, the optimized LID help to unravel dependencies between common assessment approaches. In this way this work helps to clarify the range of validity of previous research on different evaluation techniques and provides new insights on their application. As a result, a single approach providing the best visibility conditions for all lighting situations did not prove effective. The study shows that aiming on high uniformity at an adequate lighting level alone will not guarantee good visibility. Instead, a selection of average luminance, luminance uniformity, and VL leads to more meaningful results. The outcomes of this work are then combined in a catalog of recommendations, showing under which conditions the various approaches can be applied advantageously. Installation-related factors, such as the influence of the road surface or the impact of a change in pole spacing in relation to the mounting height are also discussed
D-Cycloserine in Neuropsychiatric Diseases: A Systematic Review
No full textD-Cycloserine, known from tuberculosis therapy, has been widely introduced to neuropsychiatric studies, since its central active mechanism as a partial NMDA-agonist has been found. In this review, we evaluate its therapeutic potential in neuropsychological disorders and discuss its pitfalls in terms of dosing and application frequency as well as its safety in low-dose therapy. Therefore, we identified 91 clinical trials by performing a Medline search. We demonstrate in part preliminary but increasing evidence that D-cycloserine may be effective in various psychiatric diseases, including schizophrenia, anxiety disorders, addiction, eating disorders, major depression, and autism as well as in neurological diseases, including dementia, Alzheimer's disease, and spinocerebellar degeneration. D-Cycloserine in low-dose therapy is safe, but there is still a need for new drugs with higher specificity to the different N-methyl-D-aspartate-receptor subunits
Modulating neuronal excitability in the motor cortex with tDCS shows moderate hemispheric asymmetry due to subjects' handedness: A pilot study
No full textPurpose: Transcranial direct current stimulation (tDCS) has proven to be a useful tool for fundamental brain research as well as for attempts in therapy of neurological and psychiatric diseases by modulating neuronal plasticity. Little is understood about the effects of tDCS are influenced by hemispheric dominance, even less in terms of handedness. The aim of our pilot study was to investigate whether tDCS induced neuroplastic changes may be different in right-and left-handed individuals due to existing differences in hemispheric lateralisation. Methods: We measured changes in motor evoked potentials (MEPs) after application of tDCS in 8 right-handers, 8 left-handers and 8 mixed-handers according to the Edinburgh Handedness Inventory (EHI). In double-blind sessions, we applied either anodal or cathodal tDCS for 5 minutes for each hemisphere. Results: While motor thresholds (MT) seem to be not influenced by handedness significantly, in right-handed subjects we reproduced the well-known effects of tDCS: anodal stimulation increased while cathodal stimulation decreased MEP amplitudes. However, left-and mixed-handed subjects differed from right-handed subjects. After anodal stimulation of the left hemisphere the increase of the MEP amplitudes was stronger in right handed subjects than in left and mixed handed subjects. Interestingly, after cathodal stimulation of the left hemisphere this difference was less marked. The stimulation of the right hemisphere showed the same tendency, but results were not significant. Conclusions: For the first time, we are able to demonstrate that the modulating effects of tDCS on corticospinal excitability differ moderately in the left-and mixed-handed population compared to right-handed subjects. The shown differences according to handedness should be taken into account in further studies
Levodopa Equivalent Dose Conversion Factors: An Updated Proposal Including Opicapone and Safinamide
No full textPain in Parkinson's Disease
No full textPain and discomfort in Parkinson's disease (MP) are counted as non-motor symptoms and disease have significant impact on the well-being and health satisfaction and the quality of life of PD patients. Although they occur very often, they are still too often not adequately perceived and treated. The reasons for this are, among other things, the diversity of pain and in the challenging differential diagnosis. The disease together under the umbrella term Parkinson's disease pain of various kinds analogous to chronic pain syndrome can, however, distinguish three major subgroups: the neuropathic, nociceptive and mixed pain. The pathophysiology of pain in Parkinson's disease is very complex and still unclear in many respects. New scientific findings indicate a dysfunction of the basal ganglia in the development, transfer and processing of pain. Pain may occur already in the pre-symptomatic phase of the disease and motor symptoms precede, or they occur in analogy to the motor symptoms after diagnosis. There is pain that can be alleviated by optimizing the dopaminergic medication, but also pain, show no response to Levodopa. Pain, which occur associated with motor symptoms and off phases, indicate a necessary optimization of dopaminergic medication. Botulinum toxin has proven effective in the treatment of focal dystonias. Casuistic reports on improvement of pain and dysesthesia after deep brain stimulation. Not Levodopa responsive pain should be fed a multimodal pain therapy, which should in particular take on possible interactions with Parkinson's medications consideration
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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