Publications by authors named "Molnar Mark"

The electron donor-acceptor complex-enabled asymmetric photochemical alkylation strategy holds potential to attain elusive chiral α-alkylated aldehydes without an external photoredox catalyst. The photosensitizer-free conditions are beneficial concerning process costs and sustainability. However, lengthy organocatalyst preparation steps as well as limited productivity and difficult scalability render the current approaches unsuitable for synthesis on enlarged scales.

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Inhibitory control is thought to be critical for appropriate response selection in an ever-changing environment and to decline with age. However, experimental paradigms (e.g.

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This study was to investigate the outcome of status epilepticus (SE) associated with antiepileptic therapy during SE and in follow-up period, risk factors including age, co-morbidities, pre-existing epilepsy, and etiology in the East-Hungarian region. A prospective cross-sectional database was compiled from outpatient files between 2013 and 2017. Follow-up ended on 30.

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In 2014, balanced assessment systems (BAS) were proposed as a resource-conscious, 'fit-for-purpose' form of health technology assessment for middle-income countries which lack resources and competences necessary for resource-intensive health technology assessment models. BAS has undergone extensive policy debate in the period since its publication but it has not been critically assessed in a structured form yet. This article aims to describe both the contributions and the weak spots of the original framework and to reflect on them with the intention of further developing the model.

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The organization of functional brain networks changes across human lifespan. The present study analyzed functional brain networks in healthy full-term infants (N = 139) within 1-6 days from birth by measuring neural synchrony in EEG recordings during quiet sleep. Large-scale phase synchronization was measured in six frequency bands with the Phase Lag Index.

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Goals: In the present study basic arithmetic induced rearrangements in functional connections of the brain were investigated by using graph theoretical analysis what becomes increasingly important both in theoretical neuroscience and also in clinical investigations.

Research Questions: During mental arithmetic operations (working) memory plays an important role, but there are only a few studies in which an attempt was made to separate this effect from the process of arithmetic operations themselves. The goal of our study was to separate the neural networks involved in cognitive functions.

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During daily encounters, it is inevitable that people take risks. Investigating the sequential processing of risk hazards involve expectation formation about outcome contingencies. The present study aimed to explore risk behavior and its neural correlates in sequences of decision making, particularly in old age, which represents a critical period regarding risk-taking propensity.

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Monitoring the consequences of actions is of crucial importance in order to optimize behavior to the challenges of the environment. Recently the age-related aspects of this fundamentally important cognitive processing have been brought into the focus of investigation since behavioral monitoring and related control mechanisms are widely known to be affected by aging. Processing of feedback stimuli is a core mechanism for rapid evaluation of the functionally significant aspects of outcome, guiding behavior towards avoidance or approach.

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Representations in working memory (WM) are temporary, but can be refreshed for longer periods of time through maintenance mechanisms, thereby establishing their availability for subsequent memory tests. Frontal brain regions supporting WM maintenance operations undergo anatomical and functional changes with advancing age, leading to age related decline of memory functions. The present study focused on age-related functional connectivity changes of the frontal midline (FM) cortex in the theta band (4-8 Hz), related to WM maintenance.

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Resting state EEGs were compared between patients with amnestic subtype of mild cognitive impairment (aMCI) and matched elderly controls at two times over a one year period. The study aimed at investigating the role of functional connectivity between and within different brain regions in relation to the progression of cognitive deficit in MCI. The EEG was recorded in two sessions during eyes closed and eyes open resting conditions.

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During mental arithmetic operations working memory plays an important role, but there are only few studies in which an attempt was made to separate this effect from the process of arithmetics per se. In this study the effects of arithmetic on the EEG of young adults (14 participants, six of them women, mean age 21.57 years, SD: 2.

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Introduction: Persistence with lipid-lowering drug therapy by cardiovascular patients in Hungary has not been studied previously. This study was designed to determine the rate with which Hungarian patients with hyperlipidemia persist in taking lipid-lowering agents, and to compare this with rates reported from other countries.

Material And Methods: This was a retrospective study that utilized data from the Institutional Database of the National Health Insurance Fund to analyze persistence rates with statins and ezetimibe.

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Task-dependent changes of nonlinear-linear synchronization features and graph theoretical properties of the delta and theta frequencies were analyzed in the present EEG study that were related to episodic memory maintenance processes. Synchronization was found to increase with respect to both the delta and theta bands within the frontal and parietal areas and also between these regions. Results of graph theoretical analysis indicated a task-related shift towards small-world network topology in the theta band.

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During the course of ageing the decline of cognitive performance, including attention and working memory processes--essential for arithmetic procedures--is well known. For the investigation of the neuronal mechanisms of these processes the application of methods capable of taking into account the high complexity of the nervous system, the role of nonlinear processes and network-properties of its constituents are necessary. As for the latter the recently realized small world network characteristics representing optimal conditions for information processing may be of particular importance.

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Our goal was to measure indices characterizing EEG-reactivity in young and elderly subjects. It was hypothesized that EEG-reactivity as reflected by different measures would be lower in the elderly. In two age groups (young: N= 23, mean age = 21.

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Objective And Hypothesis: Nonlinear and linear methods of EEG-complexity analysis and autonomic measures were used to characterize processes accompanying performance in a mental arithmetic task challenged by low ("social") alcohol doses. It was expected that alcohol in such doses will dampen changes of task-related EEG-synchronization in the theta band, and those of heart rate and electrodermal activity (EDA).

Methods: In the mental arithmetic task addition and working memory, effort was required.

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Objective And Hypothesis: Task-related EEG changes were studied during the performance of a mental arithmetic task, as influenced by low alcohol dosages with the presumption that even "social" drinking may have detrimental effect.

Methods: A mental arithmetic task was used in which addition and working memory effort was required. EEG spectra with an emphasis on the theta band, error rate and reaction time were analyzed in 5 (control, task, placebo-task, low-dose task [0.

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During the CNV recorded in a simple auditory working memory task, task-specific decrease of the relative delta band and a transient increase of the absolute theta band were seen, accompanied by an increase of the absolute alpha1 and alpha2 bands in the posterior region. The decreased delta power probably corresponds to increased task-evoked arousal, whereas the transient theta power increase corresponds to working memory demand and possibly to the orienting response. The increased alpha1 and alpha2 power may be a manifestation of a top-down mechanism revealing control over the execution of a response.

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The goal of this study was to investigate the EEG signs of early stage Alzheimer's disease (AD) by conventional analyses and by methods quantifying linear and nonlinear EEG-complexity. The EEG was recorded in 12 mild AD patients and in an age-matched healthy control group (24 subjects) in both eyes open and eyes closed conditions. Frequency spectra, Omega-complexity and Synchronization likelihood were calculated on the data.

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The goal of this study was to evaluate the patterns of age-dependent changes of P3 components of auditory event-related potentials exploring the effects of task difficulty. The participants (age span: 19-68 years, n=55, divided into five age groups) took part in an easy and in a difficult two-tone oddball frequency discrimination task with speed or accuracy instructions, and in a novelty oddball task. The latency of the P3 components increased with aging.

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Electroencephalographic measures combined with cognitive tasks are widely used for the assessment of cognitive and pathophysiological changes in Alzheimer's disease (AD). Instead of the analysis of EEG data obtained during the performance of the task, in this study data recorded in the immediate after-task period were analyzed. It was expected that this period would correspond to the electrophysiological consequences of the cognitive effort.

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In our study we examined the linear and non-linear characteristics of EEG signals derived from patients with Alzheimer's disease (AD) with the future aim of developing a widely available method for monitoring therapy and the progression of the disease or to be used even for the purposes of differential diagnosis. EEG was recorded with eyes closed and eyes open conditions ("resting") in a group of patients with early-stage AD and in healthy control subjects matched by age. In addition to the conventional methods of analysis (frequency spectrum, coherence), the so-called complexity measures developed in recent years (Omega-complexity, synchronised probability) have also been determined.

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Introduction: Complexity analysis of the EEG is a relatively new field in theoretical and clinical electrophysiology. The authors present results of EEG-analysis in a patient with stroke, utilizing the sensitivity of the new procedures with respect to linear and nonlinear synchronization.

Participants And Methods: The EEG (19 channels) was recorded in a patient with subcortical unilateral ischaemic completed stroke involving the frontoparietal white matter while leaving the cortex intact and in 12 healthy controls in eyes open and in eyes closed conditions.

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