Structural Analysis of Si(OEt)4 Deposits on Au(111)/SiO2 Substrates at the Nanometer Scale Using Focused Electron Beam-Induced Deposition.

The focused electron beam-induced deposition (FEBID) process was used by employing a GeminiSEM with a beam characteristic of 1 keV and 24 pA to deposit pillars and line-shaped nanostructures with heights between 9 nm and 1 µm and widths from 5 nm to 0.5 µm. All structures have been analyzed to their composition looking at a desired Si/O/C content measuring a 1:2:0 ratio. The C content of the structure was found to be ∼over 60% for older deposits kept in air (∼at room temperature) and less than 50% for later deposits, only 12 h old. Upon depositing Si(OEt)4 at high rates and at a deposition temperature of under 0 °C, the obtained Si content of our structures was between 10 and 15 atom % (compositional percentage). The FEBID structures have been deposited on Au(111)/SiO2. The Au(111) was chosen as a substrate for the deposition of Si(OEt)4 due to its structural and morphological properties. With its surface granulation following a Chevron pattern and surface defects having an increased contribution to the changes in the composition of the final structure content, the Au(111) surface characteristic behavior at the deposition of Si(OEt)4 is an increase in the O ratio and a reduction in the nanodeposit heights.

Hidden behind the mask: An authentication study on the Aztec mask of the Museum of Ethnography, Budapest, Hungary.

Turquoise covered mosaic objects - especially masks - were attractive components of treasures transported to Europe from Mexico after the fall of the Aztec Empire in the 1500s. According to our present knowledge, the mosaic masks were manufactured for ritual purpose. The main material of mosaics, the turquoise was a high-prestige semi-precious stone among Mexican native people. During the 20th century, such objects derived both from illegal treasure hunting and documented archaeological excavations. The aim of our research was the authentication of a turquoise covered Aztec wooden mask, which presumably originates from the Tehuacán Valley, Mexico and exchanged by the Museum of Ethnography, Budapest, in 1973. The detailed and complex analytical investigation of the mask is a curiosity. To reveal the origin of the object, UV photographs were taken, the wooden base was subjected to biological studies and C-14 dating, the organic glue fixing the tesserae and the inorganic mosaic tesserae were investigated by non-destructive chemical, FT-IR and Raman spectroscopic methods. Our investigations determined that the mask of the Museum of Ethnography was made of an alder species of tree and its age is AD 1492-1653. The light-coloured covering mosaic lamellae were identified as alabaster and claystone. Comparing the turquoise tesserae cover with reference materials, their chemical composition has been clearly differentiated from most of the well-known turquoise sources of the US Southwest. Based on our results, the Aztec mask of the Museum of Ethnography proved to be an original piece of art from the 15th-17th century.

Proton beam irradiation induces invisible modifications under the surface of painted parchment.

Ion beam analysis plays an important role in cultural heritage (CH) studies as it offers a combination of simultaneous and complementary analytical techniques (PIXE/PIGE/RBS) and spatially resolved mapping functions. Despite being considered non-destructive, the potential risk of beam-induced modifications during analysis is increasingly discussed. This work focuses on the impact of proton beams on parchment, present in our CH in form of unique historical manuscripts. Parchment is one of the organic, protein-based CH materials believed to be the most susceptible to radiation-induced changes. Various modification patterns, observed on parchment cross-sections by optical and electron microscopy are reported: discoloration (yellowing), formation of cavities and denaturation of collagen fibers. Considerable modifications were detected up to 100 µm deep into the sample for beam fluences of 4 µC/cm2 and higher. The presence of ultramarine paint on the parchment surface appears to increase the harmful effects of proton radiation. Based on our results, a maximum radiation dose of 0.5 µC/cm2 can be considered as 'safe boundary' for 2.3 MeV PIXE analysis of parchment under the applied conditions.

Examination of life quality, mental conditions and cognitive status of people over the age of 90: Results of a Hungarian local research.

OBJECTIVES: The study presents the findings of a quantitative research conducted among people aged over 90, who live in a large town of Hungary, Debrecen. The aim of the research was to examine the lifestyle, attitudes, values, and physical and mental condition of old and long-lived people. We laid a special emphasis on the exploration of the life perspectives, mood and mental youth, and their interconnections. METHODS: The sociological questionnaire used for data collection (159 questions) was intended to inquire socio-demographic characteristics, dietary habits, health condition, physical activity, and identity features. Further examinations were conducted in order to measure the level of depression using the Geriatric Depression Scale (GDS) and mental condition using the Mini-Mental State Examination (MMSE). We managed to reach out to the elderly living in the town on the basis of family doctors' districts (N = 212). We dealt with a subsample of 115 people since we got answers for all questions from them. During data processing, we applied multivariate statistical methods, first of all linear regression analysis and cluster analysis. We examined the differences between clusters using variation analysis. RESULTS: According to our results, the extremely low educational level of the elderly belonging to the target group did not decrease their life perspectives, but it had a significant impact on the age when their illness begun. We revealed a connection between the mental condition and the level of depression. Better mental condition (higher MMSE) resulted in lower depression level (low GDS). One of our main finding is that the change in the level of depression (GDS) is 13.4% due to the change in the mental condition (MMSE). CONCLUSIONS: Physical and mental activity, personal autonomy, a wide range of activities, and avoiding isolation and solitude allow people to experience quality ageing; all these factors can be substantially influenced by the status acquired at a younger age. We believe that it is extremely important for the society to develop guarantees for active old age, which would ensure the optimal balance between the possibilities of physical and mental health, social participation and safety.

Investigation of micronized titanium dioxide penetration in human skin xenografts and its effect on cellular functions of human skin-derived cells.

Titanium dioxide (TiO2) nanoparticles are ubiquitously used materials in everyday life (e.g. paints,household products and plastic goods). However, despite the wide array of common applications, their pathogenetic role was also suggested under certain conditions (e.g. pulmonary neoplasias and lung fibrosis). From a dermatological point of view, it is also of great importance that TiO2 also serves as a physical photoprotective agent in sunscreens and is widely used in various cosmetic products. However, the effect of TiO2 on human cutaneous functions is still unknown. Therefore, in the current study, we investigated the in vivo penetration of TiO2 via human skin transplanted to immunodeficient mice and,furthermore, we measured the in vitro effects of nanoparticles on various functional properties of numerous epidermal and dermal cells in culture. Hereby, using various nuclear microscopy methods, we provide the first evidence that TiO2nanoparticles in vivo do not penetrate through the intact epidermal barrier. However, we also report that TiO2, when exposed directly to cell cultures in vitro, exerts significant and cell-type dependent effects on such cellular functions as viability, proliferation, apoptosis and differentiation. Therefore, our novel findings will hopefully inspire one to systemically explore in future, clinically oriented trials whether there is indeed a risk from micronized TiO2-containing products on skin with an impaired stratum corneum barrier function.

Calcium distribution in the vessel wall and intima-media thickness of the human carotid arteries.

Increased common carotid artery (CCA) intima-media thickness (IMT) measured by B-mode ultrasound is an early marker of the atherosclerotic process. Arterial calcification is not clearly understood. Using the particle-induced X-ray emission (PIXE) method, we have looked for the location in the artery wall where calcium accumulated in the early phase of atherosclerosis. Twelve segments of CCAs of deceased stroke patients were investigated. In-vivo, carotid duplex ultrasound was performed with bilateral CCA IMT measurement at plaque-free sections. During autopsy, segments of carotid arteries were collected and filled under pressure with a stained histologic embedding material. The frozen arteries were cut into 60-microm-thick slices. Calcium distribution maps from the segments of arteries were determined by PIXE method. IMT measured by ultrasound and calcium distribution maps measured by PIXE were compared. In our cross-sectional study, using the PIXE analysis and ultrasound images, we could demonstrate early calcium accumulation in the media layer. Our results have also shown a significant relationship between calcium content of distributional maps measured by PIXE analysis and corresponding IMT on B-mode ultrasound images of human CCAs.

Study on the hemorheological parameters of oldest-old residents in the East-Hungarian city, Debrecen.

The aim of this study was to assess social and health status of residents older than 90 years in an East-Hungarian city. The investigation involved 70 subjects, measuring routine laboratory parameters and plasma viscosity. Mean cholesterol, erythrocyte sedimentation rate (ESR), collagen cross links and plasma viscosity values exceeded the reference range, but mean red blood cell count, hematocrit and hemoglobin were below it. Plasma viscosity was found pathologically elevated in 51% of cases. We compared these results with an earlier laboratory screening test performed on the same population with the age range of 60 to 90 years. In this cohort the mean fibrinogen concentration, ESR, HDL-cholesterol and collagen cross links values were higher, but mean cholesterol, triglyceride, total protein, hemoglobin and hematocrit values were lower than the reference range.

Effect of hemodialysis on the deformability and lipid peroxidation of erythrocytes in chronic renal failure.

Deformability and lipid peroxidation (LP) have been compared in erythrocytes of 45 chronic hemodialysis patients and 30 healthy subjects. The relative cell transit time (RCTT), correlating negatively to deformability, was measured using a St. George filtrometer. Thiobarbituric acid reactive material was measured and expressed as nanomoles of malondialdehyde (MDA) per gram of hemoglobin as a marker of LP. RCTT and MDA were found to be significantly higher not only before but also after HD compared with controls. Weak negative correlations were found between RCTT and the dosage of EPO as well as between RCTT and the daily amount of urine. These observations indicate the importance of residual renal function and the beneficial effect of EPO on erythrocyte deformability. The mean values of results suggest that HD does not affect the erythrocyte injury. The individual modifications of RCTT and MDA are also discussed.

A comparative study of hemorheological parameters in transient ischemic attack and acute ischemic stroke patients: possible predictive value.

A complete neurological and laboratory assessment was made of 31 transient ischemic attack (TIA) and 33 acute ischemic stroke patients. Laboratory parameters were compared with 33 age- and sex-matched controls. Erythrocyte deformability was characterised by determining the relative cell transit time (RCTT) with a St. George filtrometer. Plasma viscosity was measured with a Haake microviscosimeter. In comparison with controls, fibrinogen content, erythrocyte sedimentation rate (ESR), platelet and leukocyte count, erythrocyte RCTT and plasma viscosity were found to be significantly higher in stroke patients. In TIA patients the elevation of these values was not significant with the exception of platelet count. Our results suggest that the hemorheological alterations observed in TIA and stroke are largely non-specific findings and associated with the atherosclerotic disease of patients. The significant elevation of leukocytes, fibrinogen and plasma viscosity in acute stroke versus TIA probably reflects the systemic acute phase response of organism to cerebral infarction.

Early-onset carotid atherosclerosis is associated with increased intima-media thickness and elevated serum levels of inflammatory markers.

BACKGROUND AND PURPOSE: Several factors have been held responsible for the development of atherosclerosis. To avoid the masking effect of age, we evaluated correlates of carotid atherosclerosis in patients <55 years of age. METHODS: Plasma lipids, oxidative resistance of low-density lipoprotein, homocysteine, inflammatory markers, plasma viscosity, and red cell deformability were measured in fasting blood samples of 100 subjects: 45 patients with >30% stenosis of the internal carotid artery, 20 patients with carotid occlusion, and 35 control subjects. Stenosis and intima-media thickness (IMT) of the carotid artery were evaluated by duplex ultrasound. RESULTS: White blood cell (WBC) count, plasma fibrinogen, C-reactive protein (CRP), and lipoprotein(a) levels were significantly higher in patients than in control subjects, and patients had increased IMT (P<0.01 for all comparisons). There was a tendency for higher homocysteine levels in patients. Smokers had higher WBC, fibrinogen, and CRP levels. After the effect of smoking was controlled for, WBC count, natural logarithmic transform of homocysteine, and online-measured IMT remained significantly higher in patients than in control subjects. WBC, fibrinogen, and CRP levels were highest in the highest IMT quartile (P=0.012, P=0.007, and P=0.036, respectively). CONCLUSIONS: Inflammatory markers and homocysteine have a more important role than lipid factors in early-onset carotid atherosclerosis. We cannot recommend the measurement of low-density lipoprotein peroxidation as a routine screening test to identify high-risk patients for early-onset carotid atherosclerosis. The confounding effect of smoking on inflammatory markers should be considered in studies on atherosclerosis.