The Processing of Lexical Ambiguity: Evidence from Child and Adult Greek.

The aim of the study is to examine the effect of sentential context on lexical ambiguity resolution in Greek adults and typically developing children. Context and word frequency are factors that can affect lexical processing, however, the role of them has not been thoroughly examined in Greek. To this aim, we assessed sentence context effects in homonym meaning activation in monolingual speakers of Greek, children and adults, using a cross-modal priming paradigm. Additionally, all participants conducted a verbal working memory task and an inhibition task so as to examine whether the use of sentential context for lexical ambiguity resolution relates to age and/or cognitive processing capacity. The data analysis showed (a) major processing differences between adults and children due to ambiguity and sentential context, (b) children's processing times affected by cognitive skills while adults' processing unaffected, and (c) visual word recognition intact for all participants.

Aging and the Perception of Affective and Linguistic Prosody.

Investigations of affective prosodic processing have demonstrated a decline with aging. It is unclear, however, whether this decline affects all or specific emotions. Also, little is known about the ability of syntactic resolution ambiguity with the use of prosody in aging. Twenty older (age range = 70-75) and 20 younger adults (age range = 20-25) performed an affective (happiness, neutrality, sadness, surprise, fear, and anger) and a linguistic (subject/object ambiguities) prosody task. Relative to young participants, older participants faced difficulty decoding affective prosody, particularly negative emotions, and syntactic prosody, in particular the subject reading condition. A marginally positive correlation was found between the affective and syntactic prosody tasks in the group of older individuals, but no gender differences in either prosodic task. The findings of the affective prosody task are discussed under the prism of the Socioemotional Selectivity Theory, whereas general parsing strategies can account for the preference for the object reading condition.

The Comprehension of Syntactic and Affective Prosody by Adults with Autism Spectrum Disorder Without Accompanying Cognitive Deficits.

The present study investigates the comprehension of syntactic and affective prosody in adults with autism spectrum disorder without accompanying cognitive deficits (ASD w/o cognitive deficits) as well as age-, education- and gender-matched unimpaired adults, while processing orally presented sentences. Two experiments were conducted: (a) an on-line sentence completion task containing local subject/object ambiguities and (b) an affective prosody task exploring the comprehension of six emotions. The syntactic prosody task revealed that the experimental group performed similar to the control group on the fillers and the object condition. On the other hand, the ASD w/o cognitive deficits group manifested lower accuracy compared to the unimpaired controls in the subject reading condition, as well as slower reaction times in all conditions. In the affective prosody task, the experimental group performed significantly worse than the controls in the recognition of the emotion of surprise, whereas no differences between the experimental and the control group were attested in the recognition of all other emotions. A positive correlation was found between the two tasks in the ASD w/o cognitive deficits group. Thus, individuals with ASD w/o cognitive deficits face slight difficulties with the decoding of prosody, both the syntactic and the affective one. More specifically, these difficulties are attested in the most difficult conditions, i.e. the subject reading and the emotion of surprise.

Comprehension asymmetries in language acquisition: a test for Relativized Minimality.

Cross-linguistic studies have shown that typically developing children have difficulties comprehending non-canonical structures. These findings have been interpreted within the Relativized Minimality (RM) approach, according to which local relations cannot be established between two terms of a dependency if an intervening element possesses similar morphosyntactic features. In an extension of RM, Friedmann, Belletti, and Rizzi (2009) suggested that lexical NP restriction is the source of minimality effects in non-canonical sentences. The present study aimed at investigating whether the predictions of their account can be confirmed in Greek. Our results indicate that although lexical NP restriction is a crucial factor in generating minimality effects, it is not always sufficient to account for the comprehension difficulties that young children face with non-canonical sentences, since the internal structure (i.e. the feature specification) of the moved element and of the intervener affects their performance, as well.

Language Markers of Dementia and Their Role in Early Diagnosis of Alzheimer's Disease: Exploring Grammatical and Syntactic Competence via Sentence Repetition.

Background: Earlier research focuses primarily on the cognitive changes due to Alzheimer's disease (AD); however, little is known with regard to changes in language competence across the lifespan. Objective: The present study aims to investigate the decline of language skills at the grammatical and syntactic levels due to changes in cognitive function. Methods: We administered the Litmus Sentence Repetition Task (SRT) to 150 native speakers of Greek who fall into five groups: 1) young healthy speakers, 2) cognitively intact elder healthy speakers, 3) speakers with subjective cognitive impairment (SCI), 4) speakers with mild cognitive impairment (MCI); and 5) speakers with AD dementia at the mild/moderate stages. All participants underwent a physical and neurological examination and cognitive screening with a standardized neuropsychological battery to assess cognitive status comprehensively and evaluate aspects like working memory, executive function, attention and memory to appropriately classify them. Results: The data analysis revealed that the SRT had high discriminatory value in the development of AD; specifically, both accuracy and grammaticality indices were related to cognitive decline. Additionally, syntax significantly affected the performance of speakers with structures such as clitics being particularly challenging and in most structures the performance of speakers with MCI drops significantly compared to speakers with SCI. Conclusions: Linguistic indices revealed subtle early signs of cognitive decline that can be helpful in the early detection of AD, thus facilitating the clinical process offering support to language-based assessment tools such as sentence repetition, a non-invasive type of assessment to evaluate symptoms of AD.

Assessing the Linguistic Capacity Across Alzheimer's Disease and Its Preclinical Stages: Evidence from Narrative Macrostructure in Elderly Speakers of Greek.

Background: The assessment of language deficits can be valuable in the early clinical diagnosis of neurodegenerative disorders, including Alzheimer's disease (AD). Objective: The present study aims to explore whether language markers at the macrostructural level could assist with the placement of an individual across the dementia continuum employing production data from structured narratives. Methods: We administered a Picture Sequence Narrative Discourse Task to 170 speakers of Greek: young healthy controls (yHC), cognitively intact healthy elders (eHC), elder participants with subjective cognitive impairment (SCI), with mild cognitive impairment (MCI), and with AD dementia at the mild/moderate stages. Structural MRIs, medical history, neurological examination, and neuropsychological/cognitive screening determined the status of each speaker to appropriately groupthem. Results: The data analysis revealed that the Macrostructure Index, Irrelevant Info, and Narration Density markers can track cognitive decline and AD (p < 0.001; Macrostructural Index: eHC versus AD Sensitivity 93.8%, Specificity 74.4%, MCI versus AD Sensitivity 93.8%, Specificity 66.7%; Narration Density: eHC versus AD Sensitivity 90.6%, Specificity 71.8%, MCI versus AD Sensitivity 93.8%, Specificity 66.7%). Moreover, Narrative Complexity was significantly affected for subjects with AD, Irrelevant Info increased in the narrations of speakers with MCI and AD, while Narration Length did not appear to indubitably differentiate between the cognitively intact groups and the clinical ones. Conclusions: Narrative Macrostructure Indices provide valuable information on the language profile of speakers with(out) intact cognition revealing subtle early signs of cognitive decline and AD suggesting that the inclusion of language-based assessment tools would facilitate the clinical process.

Bilingualism effects in pronoun comprehension: Evidence from children with autism.

The prevalence of autism worldwide has risen steadily in the last two decades, while bilingualism is also becoming increasingly prevalent in today's rapidly globalizing world. The current study aimed to investigate bilingualism effects in the pronoun resolution skills of children with autism in comparison to age-matched monolingual children with autism, as well as monolingual and bilingual children of typical development (Ν = 20 participants per group). Results showed that autistic children had general difficulty anchoring ambiguous pronouns to entities that were linguistically expressed in discourse, yet, the bilingual children with autism were more sensitive to the topicality of the entities in syntactic subject position and more prone to identify them as suitable referents of ambiguous null pronouns as compared to their monolingual peers. The findings suggest that bilingualism is not detrimental to autistic children's pronoun resolution skills. The current study aimed at determining how bilingualism influences ambiguous pronoun comprehension in children with autism as compared to bilingual and monolingual children of typical development. The findings show that bilingualism was not detrimental to the autistic children's pronoun resolution skills, further suggesting that having acquired more than one language does not exacerbate autistic children's deficits in the comprehension of pronouns.

Getting inside on virgin olive oil (VOO) photooxidation kinetics through combined generalized 2D correlation analysis and moving window 2D correlation analysis of ATR-FTIR spectra.

The generalized two-dimensional correlation spectroscopy (g2D-COR spectroscopy) analysis combined with its extended version moving-window 2D-COR (MW-2D-COR) was performed on a set of kinetic ATR-FTIR spectral data. The former is a mathematical method that is applied to a set of spectra collected for a sample exposed to an external perturbation (e.g. storage time). Virgin olive oils (VOOs) of similar fatty acid composition, chlorophyll, and a-tocopherol content were photooxidized (10,912 Lx, no headspace, 24 h). The proposed approach revealed hidden information under specific ATR-FTIR bands and the order of events was established using appropriate rules. MW-2D-COR analysis displayed the evolution of changes during storage. In this way, the detection of the time interval upon which spectral changes are observed was evidenced. As an overview, MW plots of the analyzed samples revealed three time-zones in which changes tend to maximize, with the first one to reach a peak at ~2.5 h. The area around 2850-2930 cm-1 including bands assigned to the symmetric and asymmetric stretching vibration of the aliphatic -CH2- bonds, was the one found to be affected in all VOOs. The time interval upon which spectral changes are first detected in the corresponding area could serve as an index for the commencement of the loss of freshness. Present findings highlight the need to combine the two types of correlation analyses to obtain meaningful information on VOO photooxidation kinetics. Lipid scientists may gain an extra tool in their efforts to understand oxidation phenomena.

Differences in effective dose and energy imparted estimation from PA-AP, RLAT-LLAT projections in pediatric full spine x-ray examination using the Monte Carlo technique.

Effective dose (E) and energy imparted (epsilon) can be used to quantify the risk of radiation-induced carcinogenesis or hereditary effects arising from radiographic exposures. When the children are examined or treated for idiopathic scoliokyphosis it is important to estimate E and epsilon in the patients due to full spine x-ray examination. The aim of this study is to calculate E and epsilon in the case of children of 5 and 10 years old who undergo full spine x-ray examination using the Monte Carlo approach. Dose area product (DAP) and entrance surface dose (ESD) were also used. AP, PA, RLAT, LLAT projections are simulated by using appropriate energy spectra. According to the results, the effective dose (E) and the energy imparted (epsilon) are smaller at PA projection than AP, although for spine the opposite occurs, in agreement with previous studies. On the other hand, E and epsilon do not differ statistically among RLAT and LLAT projections. Moreover, the role of lung and bone as tissue inhomogeneities in epsilon is shown to be very important.

Barriers in implementing research findings in cancer care: the Greek registered nurses perceptions.

This study explored Greek nurses' perceptions of the barriers to research utilization faced in every day practice. The barriers between nurses working in cancer and general hospitals, as well as between those employed at central and provincial hospitals were compared. The study used a cross-sectional design and data were collected using the "Barriers Scale" (Funk et al., 1991a, Applied Nursing Research, 4, 39-45). A convenience sample of 301 nurses was randomly selected from 12 hospitals in Greece. The two key barriers identified were related to the 'availability of research findings'. English language was perceived to range between moderate and major barrier for the vast majority of participants (n = 231, 78%). Nurses surveyed indicated the presentation of research findings as the greatest barrier while the characteristics of nurses themselves were perceived as the least important one. No significant differences were found between types of hospitals (cancer/general) and geographical areas (central/provincial). Some differences, however, were observed in relation to specific items of the scale such as feeling isolated from 'research-knowledgeable' colleagues and having insufficient time to implement new ideas. The observations reported here appear to agree with the findings in mainstream literature. The results suggest that more emphasis should be given in research methodology, statistics and critical appraisal skills at all levels of nursing education, and that efforts should be made towards increasing research availability and creating supportive environments for implementation of research findings.

Estimation of children's radiation dose from cardiac catheterisations, performed for the diagnosis or the treatment of a congenital heart disease using TLD dosimetry and Monte Carlo simulation.

Entrance surface radiation doses were measured with thermoluminescent dosimeters for 98 children who were referred to a cardiology department for the diagnosis or the treatment of a congenital heart disease. Additionally, all the radiographic parameters were recorded and Monte Carlo simulations were performed for the estimation of entrance surface dose to effective dose conversion factors, in order to further calculate the effective dose for each child. For diagnostic catheterisations the values ranged from 0.16 to 14.44 mSv, with average 3.71 mSv, and for therapeutic catheterisations the values ranged from 0.38 to 25.01 mSv, with average value 5 mSv. Effective doses were estimated for diagnostic procedures and interventional procedures performed for the treatment of five different heart diseases: (a) atrial septal defect (ASD), (b) ventricular septal defect (VSD), (c) patent ductus arteriosus (PDA), (d) aorta coarctation and (e) pulmonary stenosis. The high levels of radiation exposure are, however, balanced with the advantages of cardiac catheterisations such as the avoidance of surgical closure and the necessity of shorter or even no hospitalisation.

Assessment of patient radiation doses during transcatheter closure of ventricular and atrial septal defects with Amplatzer devices.

The purpose of this study was to estimate the radiation dose to which children are exposed during cardiac catheterizations for the treatment of ventricular and atrial septal defects. Radiation doses were estimated for 46 children aged 1-18 years. These children were treated for secundum atrial septal defects (ASD group) for perimembranous ventricular septal defects (VSD group) or underwent a routine diagnostic catheterization (diagnostic group). Thermoluminescent dosimeters (TLDs) were attached in locations, representing the lateral entrance dose, the posterior entrance dose, the thyroid dose, and the gonad dose, respectively. A dose area product (DAP) meter was also attached externally on the posterior-anterior (PA) tube to give a direct value in cGy cm(2) for each procedure. The patient's entrance dose from the PA field ranged from 1.5 to 185.0 mGy for all patients, while the lateral entrance dose varied from 0.9 to 204 mGy. Radiation exposure to the thyroid and the gonads was found to vary from 0.4 to 8.3 and 0.1 to 2.1 mGy, respectively. The DAP meter recorded DAP values for the posterior tube, between 46 and 3,700 cGy cm(2). The mean effective dose was found to be 7.7, 16.2, and 33.3 mSv for the diagnostic, the ASD, and the VSD group, respectively. Very strong correlation was found between the DAP values and the entrance radiation dose measured with TLDs. The mean entrance dose received from therapeutic cardiac catheterizations using the Amplatzer devices was found approximately twice the dose received from a diagnostic one. Even for the most complex procedures, the maximum entrance dose was at least 10 times lower than the threshold, associated with skin erythema.

Polycyclic aromatic hydrocarbon contamination and LUMIStox solvent extract toxicity of marine sediments in the North Aegean Sea, Greece.

Organic extracts of surface marine sediment collected from six sites within the bay of Kavala (north Aegean Sea, Greece) were used for determining priority pollutant polycyclic aromatic hydrocarbons (PAHs) and doing toxicity testing. PAH analyses and LUMIStox acute toxicity measurements were conducted in two sediment grain-size fractions: silt/clay (< 63 microm) and sand (63-2000 microm). Sixteen PAH concentrations were found at low- to moderate levels, ranging from 44 to 166 ng/g dry weight in the fine fraction and from 45 to 148 ng/g dry weight in the coarse fraction. Molecular indices revealed that PAHs in the bay sediment originate mainly from pyrolytic sources, but some petroleum influence was also evident. A comparison of sedimentary PAH levels with sediment quality guidelines (SQGs) indicated an absence of acutely toxic concentrations. However, all sediment extracts were found to be toxic with the LUMIStox acute toxicity test, with 15-min EC(50)s in the ranges of 1.0-4.0 and 1.1-4.5 mg of dry sediment/mL for the fine and the coarse fractions, respectively. No significant correlations between EC(50)s and concentrations of individual or total PAHs was found, suggesting that chemical analysis of PAHs alone cannot be considered a reliable indicator of sediment toxicity.