bluuebunny/crossref_metadata_2025 huggingface dataset:
Contrasting between‐ and within‐individual trait effects on mortality risk in a long‐lived seabird
Authors: Zhang He , Vedder Oscar , Becker Peter H. , Bouwhuis Sandra
Published: July 2014

Individual life span is the most important determinant of lifetime reproductive success and fitness across taxa. Identifying the relationships between life‐history traits and survival therefore is fundamental to understanding the evolution of a species' traits. Especially important in this respect is to separate the contributions of between‐ and within‐individual trait effects, because only such an approach can identify markers of individual quality and expose within‐individual processes such as aging or the occurrence of costs of reproduction. Here we report a rigorous cross‐trait comparison in which we quantify effects of between‐ and within‐individual variation in phenology, body mass, and reproductive performance on mortality risk in a long‐lived seabird, the Common TernSterna hirundo. Between individuals, earlier arrival at the breeding colony, earlier egg‐laying, greater body mass, and more successful reproduction are associated with a lower mortality risk, and are markers of individual quality. The standardized between‐individual effects of arrival and laying date especially stand out, suggesting that phenology represents the best proxy for life span. In contrast, within individuals, earlier phenology, greater body mass, and more successful reproduction are associated with a higher mortality risk, as is a reduced probability of breeding. After correcting for changes in traits with age, within‐individual effects of phenology, breeding probability, clutch size, and egg volume remain significantly associated with mortality risk, which reveals survival costs of early arrival and initial investment in reproduction, but suggests terminal effects in breeding probability. Overall, our study illustrates the usefulness of separating between‐ and within‐individual trait effects on fitness measures to identify markers of individual quality and life‐history trade‐offs in natural populations.
Properties of Dissolved Organic Matter in Peatland: Implications for Water Quality after Harvest
Authors: Kiikkilä Oili , Smolander Aino , Ukonmaanaho Liisa
Published: July 2014

We studied the properties of dissolved organic matter (DOM) in drained boreal peatland in stem‐only‐harvested (SOH), whole‐tree‐harvested (WTH), and unharvested sites. The DOM derived from both aerobic and anaerobic peat layers was divided into four different molecular‐weight fractions with ultrafiltration, and the fractions were measured for the concentrations of dissolved organic C (DOC), N, and carbohydrates, aromaticity (specific ultraviolet [UV] absorbance at 254 nm), pH, and bioavailability to bacteria. The percentage of DOC in the low‐molecular‐weight (LMW) fraction was higher in the deeper than in the upper layer. We suggest that easily degradable LMW compounds with low aromatic character and high bioavailability had not degraded in the deeper layer under anaerobic conditions. This had produced a relative enrichment of LMW DOC in the anaerobic layer. A different relation to aerobicity was observed in alternating aerobic conditions in the upper layer alone, where the high‐molecular‐weight compounds seemed to increase under more anaerobic conditions. Thus the properties and processes of DOM in peatlands seem to be controlled by the aerobicity in a complicated manner. We suggest that operations that affect the water table level in peatland affect also the properties of peat DOM. The properties of DOM that could be connected to clear‐cut harvest‐induced changes in the recent inputs of C and N were small. Peat DOM was more N rich in harvested than in control sites. Thus it seems possible that N is susceptible to leaching after harvest in naturally relatively N‐rich sites and especially in mineral form.
Equations of viscous flow of silicate liquids with different approaches for universality of high temperature viscosity limit
Authors: Kozmidis-Petrovic Ana
Published: July 2014

The Vogel-Fulcher-Tammann (VFT), Avramov and Milchev (AM) as well as Mauro,
Yue, Ellison, Gupta and Allan (MYEGA) functions of viscous flow are analysed
when the compositionally independent high temperature viscosity limit is
introduced instead of the compositionally dependent parameter ??. Two
different approaches are adopted. In the first approach, it is assumed that
each model should have its own (average) hightemperature viscosity parameter
??. In that case, ?? is different for each of these three models. In the
second approach, it is assumed that the high-temperature viscosity is a truly
universal value, independent of the model. In this case, the parameter ??
would be the same and would have the same value: log ?? = ?1.93 dPa?s for all
three models. 3D diagrams can successfully predict the difference in
behaviour of viscous functions when average or universal high temperature
limit is applied in calculations. The values of the AM functions depend, to a
greater extent, on whether the average or the universal value for ?? is used
which is not the case with the VFT model. Our tests and values of standard
error of estimate (SEE) show that there are no general rules whether the
average or universal high temperature viscosity limit should be applied to
get the best agreement with the experimental functions.
Synthesis and characterization of biomorphic CeO2 obtained by using egg shell membrane as template
Authors: Prekajski Marija , Babic Biljana , Bucevac Dusan , Pantic Jelena , Gulicovski Jelena , Miljkovic Miroslav , Matovic Branko
Published: July 2014

A new technology based on bio-templating approach was proposed in this paper.
Egg-shell membrane (ESM) has been employed as a natural biotemplate. Fibrous
oxide ceramics was prepared by wet impregnation of biological template with
water solution of cerium nitrate. The template was derived from membranes of
fresh chicken eggs. Repeated impregnation, pyrolysis and final calcination in
the range of 600 to 1200?C in air resulted in template burnout and
consolidation of the oxide layers. At low temperatures, the obtained products
had structure which corresponded to the negative replication of biological
templates. Unique bio-morphic CeO2 microstructures with interwoven networks
were synthesized and characterized by scanning electron microscope (SEM) and
X-ray diffraction (XRD), whereas low-temperature nitrogen adsorption (BET)
method was used in order to characterize porous properties.
Core/shell magnetic mesoporous silica nanoparticles with radially oriented wide mesopores
Authors: Knezevic Nikola
Published: July 2014

Core/shell nanoparticles, containing magnetic iron-oxide (maghemite) core and
mesoporous shell with radial porous structure, were prepared by dispersing
magnetite nanoparticles and adding tetraethylorthosilicate to a basic aqueous
solution containing structure-templating cetyltrimethylammonium bromide and a
pore-swelling mesithylene. The material is characterized by SEM and TEM
imaging, nitrogen sorption and powder X-ray diffraction. Distinctive features
of the prepared material are its high surface area (959m2/g), wide average
pore diameter (12.4 nm) and large pore volume (2.3 cm3/g). The material
exhibits radial pore structure and the high angle XRD pattern characteristic
for maghemite nanoparticles, which are obtained upon calcination of the
magnetite-containing material. The observed properties of the prepared
material may render the material applicable in separation, drug delivery,
sensing and heterogeneous catalysis.
Contagion effects of the global financial crisis in us and European real economy sectors
Authors: Kenourgios Dimitris , Dimitriou Dimitrios
Published: July 2014

This paper empirically investigates the contagion effects of the Global
Financial Crisis (2007-2009) from the financial sector to the real economy
by examining nine sectors of US and developed European region. We provide a
regional analysis by testing stock market contagion on the aggregate level
and the sector level, on the global level and the domestic/regional level.
Results show evidence of global contagion in US and developed European
aggregate stock market indices and all US sector indices, implying the
limited benefits of portfolio diversification. On the other hand, most of
the European regional sectors seem to be immune to the adverse effects of
the crisis. Finally, all non-financial sectors of both geographical areas
seem to be unaffected by their domestic financial systems. These findings
have important implications for policy makers, investors and international
organizations.
Aging population and public pensions: Theory and macroeconometric evidence
Authors: Verbic Miroslav , Spruk Rok
Published: July 2014

Rapidly aging population in high-income countries has exerted additional
pressure on the sustainability of public pension expenditure. We present a
theoretical model of public pension expenditure under endogenous human
capital, where the latter facilitates a substantial decrease in equilibrium
fertility rate alongside the improvement in life expectancy. We demonstrate
how higher life expectancy and human capital endowment facilitate a rise of
net replacement rate. We then provide and examine an empirical model of
old-age expenditure in a panel of 33 countries for the period 1998-2008. Our
results indicate that increases in effective retirement age and total
fertility rate would reduce age-related expenditure substantially. While
higher net replacement rate would alleviate the risk of old-age poverty,
further increases would add considerable pressure on the fiscal
sustainability of public pensions.
Development of a methodology of evaluation of financial stability of commercial banks
Authors: Brauers Willem , Ginevicius Romualdas , Podviezko Askoldas
Published: July 2014

The field of evaluation of financial stability of commercial banks, which
emanates from persistent existence of financial crisis, induces interest of
researchers for over a century. The span of prevailing methodologies
stretches from over-simplified risk-return approaches to ones comprising
large number of economic variables on the micro- and/or macro-economic level.
Methodologies of rating agencies and current methodologies reviewed and
applied by the ECB are not intended for reducing information asymmetry in the
market of commercial banks. In the paper it is shown that the Lithuanian
financial system is bankbased with deposits of households being its primary
sources, and its stability is primarily depending on behavior of depositors.
A methodology of evaluation of commercial banks with features of decreasing
information asymmetry in the market of commercial banks is being developed by
comparing different MCDA methods.
Did economic inequality cause the economic crisis
Authors: Sukovic Danilo
Published: July 2014

The sudden and large increase of interest in questions of distribution of
wealth and economic inequality, arising in recent years, resulted primarily
from the enormous increase in inequality that occurred during the last three
decades. The global economic crisis that emerged in 2008 gave a new impetus
to this research because numerous scientific studies appeared in which
inequalities were given as one of the key causes of the crisis from which the
world is slowly recovering. This is especially true in Europe, whose recovery
is barely discernible. This paper analyzes the trends of economic inequality
and points to the impact of inequality on economic growth. The central
question in this paper, however, is whether the economic inequalities caused
the economic crisis. Although opinions differ as to inequality?s impact on
the occurrence of the crisis, the fact is that enormous economic
inequalities, and especially their permanent growth, could have many negative
effects, such as increasing poverty, increasing social stratification and
causing global economic crises. As many authors have pointed out, escalating
inequality is not an inevitable price of progress. On the contrary, it is a
political decision that often has expensive ramifications.
A practical field study of performances of solar modules at various positions in Serbia
Authors: Pantic Lana , Pavlovic Tomislav , Milosavljevic Dragana
Published: July 2014

In this paper, results of practical field study of performances of three
identical monocrystalline solar modules, single power of 60 W, with different
inclinations (horizontal, optimally inclined oriented toward South and
vertically oriented toward South) in real meteorological conditions, in Nis,
Serbia, in 2013, are presented. On the basis of the measurement results of
solar energy intensity and electrical power generated with solar modules,
efficiency (?), Performance Ratio (PR) and fill factor (FF) were calculated.
In 2013, optimally inclined solar module generated 62.8 kWh, horizontal solar
module 58.1 kWh and vertical solar module 43.9 kWh of electrical energy. It
was found that annually the vertical solar module had the highest value of
efficiency (10.9%), then horizontal solar module (10.6%) and finally,
optimally inclined solar module (10.2%). Annually, the vertical solar module
had the highest value of Performance Ratio (0.93), then follows horizontal
solar module (0.91) and finally, optimally inclined solar module (0.86).
Annually, the horizontal solar module had the highest value of Fill Factor
(67.7), then follows vertical solar module (66.6) and, finally, optimally
inclined solar module (63.3). It was found that embodied energy payback time
(EEPBT) for a horizontal, optimally inclined and vertical BIPV system of
1020Wp would be 11.8, 10.9 and 15.6 years, respectively. The results obtained
by this study could be used in planning and constructing building-integrated
photovoltaics (BIPV), in Serbia.
Histological characteristics and markers of proliferation and differentiation in rat brain with experimental glioma
Authors: Ristic Slavica , Miric Mirjana , Jovic Sladjana , Ristic Sinisa , Karic Jasmina
Published: July 2014

Background/Aim. The cell line C6 is a continuous cell line of rat glioma and,
as a transplantable line, is frequently used for induction into in vivo model
of primary brain tumor. It is believed that, pursuant to its histological
traits and biological behavior, this experimental tumor corresponds to human
anaplastic astrocytoma of grade II/III, which is characterized by
proliferative and invasive potency, and marked cell differentiation. The aim
of this study was to determine macroscopic analysis of rat brain with
implanted tumor during tumorigenesis, histological features of tumor cells of
induced brain tumor and markers of proliferation (proliferation cell nuclear
antigen - PCNA, cytokeratin - CK 19) and differentiation (glial fibrillary
acidic protein -GFAP) in rat brain with implanted tumor. Methods. To
determine histological structure of the brain with implanted C6 cells, we
used brain sections stained for hematoxylin-eosin or kresyl violet, whereas
other sections were immunohistochemically stained for GFAP, CK 19 and PCNA.
Results. A statistically significant difference in weights of the left and
right brain hemispheres with implanted tumors during tumorigenesis in as soon
as 7 days from the day of inducing tumors was revealed. The tumor was of
cellular type, with distinct pleomorphism of cells and frequent
hyperchromasia of the nucleus. Immunohistochemical staining for PCNA revealed
a significant number of positive cells on the days 7, 14 and 21 day following
the implantation of C6 cells. CK 19 positive cells were present in both brain
hemispheres, and numerous GFAP positive astrocytes were found around the
puncture lesion. Conclusions. Within the experimental conditions of the
present research, C6 glioma did not demonstrate any relevant deviations
concerning development, clinical symptomatology and macroscopic anatomy
relative to those already described in the literature.
Melanoma risk prediction models
Authors: Nikolic Jelena , Loncar-Turukalo Tatjana , Sladojevic Srdjan , Marinkovic Marija , Janjic Zlata
Published: July 2014

Background/Aim. The lack of effective therapy for advanced stages of melanoma
emphasizes the importance of preventive measures and screenings of population
at risk. Identifying individuals at high risk should allow targeted
screenings and follow-up involving those who would benefit most. The aim of
this study was to identify most significant factors for melanoma prediction
in our population and to create prognostic models for identification and
differentiation of individuals at risk. Methods. This case-control study
included 697 participants (341 patients and 356 controls) that underwent
extensive interview and skin examination in order to check risk factors for
melanoma. Pairwise univariate statistical comparison was used for the coarse
selection of the most significant risk factors. These factors were fed into
logistic regression (LR) and alternating decision trees (ADT) prognostic
models that were assessed for their usefulness in identification of patients
at risk to develop melanoma. Validation of the LR model was done by Hosmer
and Lemeshow test, whereas the ADT was validated by 10-fold cross-validation.
The achieved sensitivity, specificity, accuracy and AUC for both models were
calculated. The melanoma risk score (MRS) based on the outcome of the LR
model was presented. Results. The LR model showed that the following risk
factors were associated with melanoma: sunbeds (OR = 4.018; 95% CI 1.724-
9.366 for those that sometimes used sunbeds), solar damage of the skin (OR =
8.274; 95% CI 2.661-25.730 for those with severe solar damage), hair color
(OR = 3.222; 95% CI 1.984-5.231 for light brown/blond hair), the number of
common naevi (over 100 naevi had OR = 3.57; 95% CI 1.427-8.931), the number
of dysplastic naevi (from 1 to 10 dysplastic naevi OR was 2.672; 95% CI
1.572-4.540; for more than 10 naevi OR was 6.487; 95%; CI 1.993-21.119),
Fitzpatricks phototype and the presence of congenital naevi. Red hair,
phototype I and large congenital naevi were only present in melanoma patients
and thus were strongly associated with melanoma. The percentage of correctly
classified subjects in the LR model was 74.9%, sensitivity 71%, specificity
78.7% and AUC 0.805. For the ADT percentage of correctly classified instances
was 71.9%, sensitivity 71.9%, specificity 79.4% and AUC 0.808. Conclusion.
Application of different models for risk assessment and prediction of
melanoma should provide efficient and standardized tool in the hands of
clinicians. The presented models offer effective discrimination of
individuals at high risk, transparent decision making and real-time
implementation suitable for clinical practice. A continuous melanoma database
growth would provide for further adjustments and enhancements in model
accuracy as well as offering a possibility for successful application of more
advanced data mining algorithms.
Unintended Consequences of Lowering Disclosure Thresholds
Authors: Fanning Kirsten , Agoglia Christopher P. , Piercey M. David
Published: July 2014

In recent years, regulators have considered several initiatives to lower the threshold for disclosing risks to investors. We examine two ways in which disclosing more risks can actually lower investors' perceptions of risk. Utilizing an experiment, we find evidence of two unintended consequences on different types of investors. First, we demonstrate that the addition of low-probability risks to a disclosure can dilute (rather than add to) more probable losses, leading certain investors to lower their perceptions of overall risk. Second, since lowering the threshold changes the overall composition of the disclosure by adding low-probability losses, firms could adopt a tactic of minimization that characterizes the entire disclosure as unimportant, presenting the lowest risks most saliently, using compliance with the low threshold as a plausible reason for giving a lengthy disclosure of generally unimportant risks. Our findings suggest that such a tactic can be persuasive.

Data Availability: Contact the authors.
Contributors to Mortality in High-Risk Diabetic Patients in the Diabetes Heart Study
Authors: Cox Amanda J. , Hsu Fang-Chi , Freedman Barry I. , Herrington David M. , Criqui Michael H. , Carr J. Jeffrey , Bowden Donald W.
Published: July 2014

OBJECTIVE

Not all individuals with type 2 diabetes and high coronary artery calcified plaque (CAC) experience the same risk for adverse outcomes. This study examined a subset of high-risk individuals based on CAC >1,000 mg (using a total mass score) and evaluated whether differences in a range of modifiable cardiovascular disease (CVD) risk factors provided further insights into risk for mortality.

RESEARCH DESIGN AND METHODS

We assessed contributors to all-cause mortality among 371 European American individuals with type 2 diabetes and CAC >1,000 from the Diabetes Heart Study (DHS) after 8.2 ± 3.0 years (mean ± SD) of follow-up. Differences in known CVD risk factors, including modifiable CVD risk factors, were compared between living (n = 218) and deceased (n = 153) participants. Cox proportional hazards regression models were used to quantify risk for all-cause mortality.

RESULTS

Deceased participants had a longer duration of type 2 diabetes (P = 0.02) and reduced use of cholesterol-lowering medications (P = 0.004). Adjusted analyses revealed that vascular calcified plaque scores were associated with increased risk for mortality (hazard ratio 1.31–1.63; 3.89 × 10−5 < P < 0.03). Higher HbA1c, lipids, and C-reactive protein and reduced kidney function also were associated with a 1.1- to 1.5-fold increased risk for mortality (3.45 × 10−6 < P < 0.03) after adjusting for confounding factors.

CONCLUSIONS

Even in this high-risk group, vascular calcification and known CVD risk factors provide useful information for ongoing assessment. The use of cholesterol-lowering medication seemed to be protective for mortality.
Influence of Chemical Composition on Porosity in Aluminium Alloys
Authors: Kucharčík L. , Brůna M. , Sládek A.
Published: July 2014

Porosity is one of the major defects in aluminum castings, which results is a decrease of a mechanical properties. Porosity in aluminum alloys is caused by solidification shrinkage and gas segregation. The final amount of porosity in aluminium castings is mostly influenced by several factors, as amount of hydrogen in molten aluminium alloy, cooling rate, melt temperature, mold material, or solidification interval. This article deals with effect of chemical composition on porosity in Al-Si aluminum alloys. For experiment was used Pure aluminum and four alloys: AlSi6Cu4, AlSi7Mg0, 3, AlSi9Cu1, AlSi10MgCu1.
The Evaluation of the Corrosion Resistance of the Al-Si Alloys Antimony Alloyed
Authors: Svobodova J. , Cais J. , Weiss V.
Published: July 2014

This paper deals with the evaluation of the corrosion resistance of the Al-Si alloys alloyed with the different amount of antimony. Specifically it goes about the alloy AlSi7Mg0,3 which is antimony alloyed in the concentrations 0; 0,001; 0,005; 0,01 a 0,05 wt. % of antimony. The introduction of the paper is dedicated to the theory of the aluminium alloys corrosion resistance, testing and evaluation of the corrosion resistance. The influence of the antimony to the Al-Si alloys properties is described further in the introduction. The experimental part describes the experimental samples which were prepared for the experiment and further they were exposed to the loading in the atmospheric conditions for a period of the 3 months. The experimental samples were evaluated macroscopically and microscopically. The results of the experiment were documented and the conclusions in terms of the antimony impact to the corrosion resistance of the Al-Si alloy were concluded. There was compared the corrosion resistance of the Al-Si alloy antimony alloyed (with the different antimony content) with the results of the Al-Si alloy without the alloying after the corrosion load in the atmospheric conditions in the experiment.
Correlations Between Arrangement of Reinforcing Particles and Mechanical Properties in Pressure Die Cast AlSi11-SiC Composites
Authors: Konopka Z. , Pasieka A. , Łągiewka M. , Nadolski M. , Zyska A.
Published: July 2014

The work presents the investigation results concerning the structure of composite pressure die castings with AlSi11 alloy matrix reinforced with SiC particles. Examination has been held for composites containing 10 and 20 volume percent of SiC particles. The arrangement of the reinforcing particles within the matrix has been qualitatively assessed in specimens cut out of the castings. The index of distribution was determined on the basis of particle count in elementary measuring fields. The tensile strength, the yield point and elongation of the obtained composite were measured. Composite castings were produced at various values of the piston velocity in the second stage of injection, diverse intensification pressure values, and various injection gate width values. The regression equation describing the change of the considered arrangement particles index and mechanical properties were found as a function of the pressure die casting parameters. The infuence of particle arrangement in composite matrix on mechanical properties these material was examined and the functions of correlations between values were obtained. The conclusion gives the analysis and the interpretation of the obtained results.
Formation of Structure and Properties in Casting Processes on the Example of AZ91 Magnesium Alloy
Authors: Augustyn B. , Szymanek M. , Kapinos D. , Boczkal S. , Korczak P.
Published: July 2014

Contemporary materials engineering requires the use of materials characterised by high mechanical properties, as these precisely properties determine the choice of material for parts of machinery and equipment. Owing to these properties it is possible to reduce the weight and, consequently, the consumption of both material and energy. Trying to meet these expectations, the designers are increasingly looking for solutions in the application of magnesium alloys as materials offering a very beneficial strength-to-weight ratio. However, besides alloying elements, the properties are to a great extent shaped by the solidification conditions and related structure. The process of structure formation depends on the choice of casting method forced by the specific properties of casting or by the specific intended use of final product. The article presents a comparison of AZ91 magnesium alloys processed by different casting technologies. A short characteristic was offered for materials processed by the traditional semi-continuous casting process, which uses the solidification rates comprised in a range of 5 - 20°C/s, and for materials made in the process of Rapid Solidification, where the solidification rate can reach 106 °C/s. As a result of the casting process, a feedstock in the form of billets and thin strips was obtained and was subjected next to the process of plastic forming. The article presents the results of structural analysis of the final product. The mechanical properties of the ø7 mm extruded rods were also evaluated and compared.
The Assessment of Modification of High-Zinc Aluminium Alloy
Authors: Zyska A. , Konopka Z. , Łągiewka M. , Nadolski M.
Published: July 2014

The results of examinations of the influence of titanium-boron inoculant on the solidification, the microstructure, and the mechanical properties of AlZn20 alloy are presented. The examinations were carried out for specimens cast both of the non-modified and the inoculated alloy. There were assessed changes in the alloy overcooling during the first stage of solidification due to the nuclei-forming influence of the inoculant. The results of quantitative metallographic measurements concerning the refinement of the grain structure of casting produced in sand moulds are presented. The cooling rate sensitivity of the alloy was proved by revealing changes in morphology of the α-phase primary crystals. Differences in mechanical properties resulting from the applied casting method and optional inoculation were evaluated.
Effect of Microstructure on Mechanical Properties of BA1055 Bronze Castings
Authors: Łabanowski J. , Olkowski T.
Published: July 2014

The article presents research results performed on aluminum bronze CuAl10Fe5Ni5 (BA1055) castings used for marine propellers. Metallographic studies were made on light microscope and a scanning electron microscope to assess quantitatively and qualitatively the alloy microstructure. It has been shown that the shape, size and distribution of the iron-rich к−phase precipitates in bronze microstructure significantly affect its mechanical properties. With an increase in the number of small к−phase precipitates increases the tensile strength of castings, while the presence of large globular precipitates improves ductility. Fragmentation and shape of κ−phase precipitates depends on many factors, particularly on the chemical composition of the alloy, Fe/Ni ratio, cooling rate and casting technology.
Physical Properties of Copper Based MMC Strengthened with Alumina
Authors: Kaczmar J. W. , Granat K. , Kurzawa A. , Grodzka E.
Published: July 2014

The aim of this work is the development of Cu-Al2O3 composites of copper Cu-ETP matrix composite materials reinforced by 20 and 30 vol.% Al2O3 particles and study of some chosen physical properties. Squeeze casting technique of porous compacts with liquid copper was applied at the pressure of 110 MPa. Introduction of alumina particles into copper matrix affected on the significant increase of hardness and in the case of Cu-30 vol. % of alumina particles to 128 HBW. Electrical resistivity was strongly affected by the ceramic alumina particles and addition of 20 vol. % of particles caused diminishing of electrical conductivity to 20 S/m (34.5% IACS). Thermal conductivity tests were performed applying two methods and it was ascertained that this parameter strongly depends on the ceramic particles content, diminishing it to 100 Wm-1K-1 for the composite material containing 30 vol.% of ceramic particles comparing to 400 Wm-1K-1 for the unreinforced copper. Microstructural analysis was carried out using SEM microscopy and indicates that Al2O3 particles are homogeneously distributed in the copper matrix. EDS analysis shows remains of silicon on the surface of ceramic particles after binding agent used during preparation of ceramic preforms.
Properties and Structure of High-Silicone Austempered Ductile Iron
Authors: Krzyńska A. , Kochański A.
Published: July 2014

The results presented in this paper are a continuation of the previously published studies. The results of hest treatment of ductile iron with content 3,66%Si and 3,80% Si were produced. The experimental castings were subjected to austempering process for time 30, 60 and 90 minutes at temperature 300°C. The mechanical properties of heat treated specimens were studied using tensile testing and hardness measurement, while microstructures were evaluated with conventional metallographic observations. It was again stated that austempering of high silicone ferritic matrix ductile iron allowed producing ADI-type cast iron with mechanical properties comparable with standard ADI.
The Effect of Aluminium on Graphitization of Cast Iron Treated with Cerium Mixture
Authors: Soiński M. S. , Jakubus A. , Kordas P. , Skurka K.
Published: July 2014

The work determined the influence of aluminium in the amount from about 0.6% to about 8% on graphitization of cast iron with relatively high silicon content (3.4%-3.9%) and low manganese content (about 0.1%). The cast iron was spheroidized with cerium mixture and graphitized with ferrosilicon. It was found that the degree of graphitization increases with an increase in aluminium content in cast iron up to 2.8%, then decreases. Nodular and vermicular graphite precipitates were found after the applied treatment in cast iron containing aluminium in the amount from about 1.9% to about 8%. The Fe3AlCx carbides, increasing brittleness and deteriorating the machinability of cast iron, were not found in cast iron containing up to about 6.8% Al. These carbides were revealed only in cast iron containing about 8% Al.
Effect of Electrical Properties of Materials on Effectiveness of Heating Their Systems in Microwave Field
Authors: Stachowicz M. , Opyd B. , Granat K. , Markuszewska K.
Published: July 2014

In the paper presented are results of a research on influence of electrical and physico-chemical properties of materials being parts of multicomponent and multimaterial systems used in foundry practice on efficiency and effectiveness of microwave heating. Effectiveness of the process was evaluated on the grounds of analysis of interaction between selected parameters of permittivity and loss factor, as well as collective index of energy absorbed, reflected and transmitted by these materials. In the examinations used was a stand of waveguide resonance cavity for determining electrical properties and a stand of microwave slot line for determining balance of microwave power emitted into selected materials. The examinations have brought closer the possibility of forecasting the behaviour of multimaterial systems like e.g. model, moulding sand or moulding box in microwave field on the grounds of various electrical and physico-chemical properties. On the grounds of analysis of the results, possible was selecting a group of materials designed for building foundry instrumentation to be effectively used in electromagnetic field.
Using of the Reverse Engineering Method for the Production of Prototype Molds by Patternless Process Technology
Authors: Krivoš E. , Pastirčák R. , Lehocký P.
Published: July 2014

The present article deals with the possibility of using the reverse engineering method for the production of prototype molds by Patternless process technology. Article describes method how to obtain virtual model by using a 3D scanner. Article also explains principle of the Patternless process technology, which is based on the milling mold cavity using CNC machining equipment. The aim of the research is the use of advanced technologies that speed up and facilitate the process of production prototype mold. The practical result of the presented experiment is bronze casting, which serves as a foot rest bracket on historic bike.
A reassessment of the Pennsylvanian lycophyte cone Triplosporite Brown
Authors: Thomas Barry A. , Bek Jiří
Published: July 2014

The type collection of the lycopsid cone species Triplosporite brownii Unger was re-examined to assess its in situ spores. The cones are monosporangiate with only microspores that possess both cingulum and zona. They equate to the dispersed miospore genus Lycospora and would be identified as Lycospora cf. pseudoannulata. Therefore, the genus Triplosporite Brown is shown to be a junior synonym to Lepidostrobus and a species emendation is given. A comparison is given with the other Lepidostrobus cones which yielded similar in situ microspores of the Lycospora pellucida Group.
Dobrogeria aegyssensis, a new early Spathian (Early Triassic) coelacanth from North Dobrogea (Romania)
Authors: Cavin Lionel , Grădinaru Eugen
Published: July 2014

The Early Triassic witnessed the highest taxic diversity of coelacanths (or Actinistia), a clade with a single living genus today. This peak of diversity is accentuated here with the description of a new coelacanth discovered in the lower Spathian (Upper Olenekian, Lower Triassic) cropping out in the Tulcea Veche (Old Tulcea) promontory, in the city of Tulcea, in North Dobrogea, Romania. The bone remains were preserved in a block of limestone, which was chemically dissolved. The resulting 3D and matrix-free ossifications correspond mostly to elements of the skull and branchial apparatus. Posterior parietals, postparietal with associated prootic and basisphenoid allow a precise description of the neurocranium. Ossifications of the lower jaw, together with branchial and pectoral elements, complete the description of this coelacanth and support the coining of a new generic and specific name, Dobrogeria aegyssensis. A phylogenetic analysis of actinistians with the new species recovers clades which were found in most recent analyses, i.e. the Sasseniidae, the Laugiidae, the Coelacanthiformes, the Latimerioidei, the Mawsoniidae and the Latimeriidae, and identifies the new taxon as a non-latimerioid coelacanthiform.
An early Middle Anisian (Middle Triassic) Tubiphytes and cement crusts-dominated reef from North Dobrogea (Romania): facies, depositional environment and diagenesis
Authors: Popa Livia , Panaiotu Cristina E. , Grădinaru Eugen
Published: July 2014

A well-developed Triassic carbonate platform is exposed in the eastern part of the Tulcea Unit, in the Cimmerian North Dobrogean Orogen, southeastern Romania. Facies analysis of the 200 m thick succession of lower Middle Anisian limestones exposed in a large limestone quarry south of the village of Mahmudia suggests a transition from upper slope towards toe-of-slope carbonate facies, reflecting sea-level fluctuations and tectonic tilting. The slope is dominated by in situ microbialites in the upper portion, consisting of reefal boundstone facies, and by molluscan coquina and cement boundstones. A key role is played by the cosmopolitan micro-encruster Tubiphytes, which became common in the aftermath of the mass extinction at the Permian/Triassic boundary, and by autochthonous micrite and synsedimentary marine cement. The absence of metazoan reef builders, such as sponges and corals, reflects the fact that microbes were the first organisms to recover after the Permian/Triassic crisis under unusual marine conditions and that their main role in reef formation was sediment stabilization along the upper slopes. The lower slope is mostly detrital, being dominated by platform-derived bioclastic rudstones and crinoidal floatstones, which are interbedded with basinal carbonate hemipelagics. The toe-of-slope is composed of pelagic wackestones framed by thin tongues of intraclast breccia. All these observations are in agreement with the slopeshedding model described for the Pennsylvanian microbial margin in Asturias (northern Spain) and the Anisian- Ladinian flat-topped, steep-rimmed Latemar platform (Dolomites, Italy).

As most of the Anisian reefs were described from western and eastern Tethys (Southern Alps, Hungary, China), the occurrence of the early Middle Anisian Tubiphytes-reef from North Dobrogea (Romania) contributes to resolving the puzzle of the geographic distribution of reef recovery in the Middle Triassic.
Verification of Brittle Fracture Criteria for Bimaterial Structures
Authors: Mieczkowski Grzegorz , Molski Krzysztof
Published: July 2014

The increasing application of composite materials in the construction of machines causes strong need for modelling and evaluating their strength. There are many well known hypotheses used for homogeneous materials subjected to monotone and cyclic loading conditions, which have been verified experimentally by various authors. These hypotheses should be verified also for composite materials. This paper provides experimental and theoretical results of such verifications for bimaterial structures with interfacial cracks. Three well known fracture hypotheses of: Griffith, McClintock and Novozhilov were chosen. The theoretical critical load values arising from each hypotheses were compared with the experimental data including uni and multi-axial loading conditions. All tests were carried out with using specially prepared specimens of steel and PMMA.
The Effect of Aluminum Content on the Microstructure and Cavitation Wear of Feal Intermetallic Alloys
Authors: Jasionowski Robert , Zasada Dariusz , Polkowski Wojciech
Published: July 2014

Intermetallic-based alloys (so called intermetallics) of the Fe-Al binary system are modern construction materials, which in recent decades have found application in many branches of the power, chemical and automotive industries. High resistance of FeAl based alloys to cavitational erosion results first of all from their high hardness in the as-cast state, large compressive stresses in the material, as well as homogeneous structure. In the present paper, the effect of aluminum content on the microstructure, texture and strain implemented upon cavitation wear of FeAl intermetallic alloys, have been analyzed by field emission gun scanning electron microscopy (FEG SEM) and electron backscatter diffraction (EBSD) analysis. Obtained results of structural characterization indicates that with increasing aluminium content effects of orientation randomization (weakening of <100>//ND casting texture), grain refinement and rising of mechanical strenght (and so cavitational resistance) take place.
Intra-operator Reliability of a 2D Image Analysing Method for Tooth Dimension Measurements
Authors: Kerekes-Máthé Bernadette , Mártha Krisztina , Melinda Székely
Published: July 2014

Objective: The aim of this study was to evaluate the intra-operator reliability of a 2D image analysis method for tooth dimension measurements.

Methods: Occlusal and vestibular surfaces of teeth from ten study models were captured with a digital camera. Images were transferred on a computer and different tooth dimensions (mesio-distal, occluso-gingival, vestibulo-oral and perimeter) were measured using the Image Pro Insight software. Measurements were repeated after two weeks. Fleiss' coefficients of reliability were calculated.

Results: A high degree of reliability has been established for every type of measurement: all coefficient values of reliability being not less than 0.95.

Conclusions: The 2D image analyzing system is an adequate alternative for measuring tooth dimensions. All measurements were in the excellent category of reliability. The method allows precise and repeatable measurements, generating an image database as well, available for future studies.
Lichens from Iceland in the Collection of Svanhildur Svane
Authors: Kristinsson Hörður , Heiðmarsson Starri , Hansen Eric Steen
Published: July 2014

Kristinsson H., Heiðmarsson S., Hansen E. S., 2014: Lichens from Iceland in the collection of Svanhildur Svane [Islandijos kerpės Svanhildur Svane kolekcijoje]. - Bot. Lith., 20(1): 14-18.

Survey was made of the lichens collected by Svanhildur Svane in different parts of Iceland from 1949 to 1997 and deposited at the Botanical Museum of the University of Copenhagen (C). As a result, 11 species, Agonimia tristicula, Aspicilia mashiginensis, Fuscidea tenebrica, Gyalecta flotowii, Lecania baeomma, Lithographa tesserata, Pyrenopsis grumulifera, Rimularia fuscosora, Steinia geophana, Thelignya lignyota and Umbilicaria nylanderiana, were recorded as new to Iceland, and 6 species were new to certain regions in Iceland as defined in the Nordic Lichen Flora
Interrelationships Among some Morphological Traits of Wheat (Triticum Aestivum L.) Cultivars using Biplot
Authors: Sabaghnia Naser , Janmohammadi Mohsen
Published: July 2014

Sabaghnia N., Janmohammadi M., 2014: Interrelationships among some morphological traits of wheat (Triticum aestivum L.) cultivars using biplot [Kviečių (Triticum aestivum L.) veislių morfologinių požymių sąveika naudojant biplot metodą]. - Bot. Lith., 20(1): 19-26.

Wheat (Triticum aestivum L.) is one of the major food crops worldwide and Iran produces about 14 million tons of wheat annually. Effective interpretation of the data on breeding programmes is important at all stages of plant improvement. The cultivar by trait (CT) biplot was used for two-way wheat dataset as cultivars with multiple traits. For this propose, 13 wheat cultivars with specific characteristics were tested and the CT biplot for wheat dataset explained 65% of the total variation of the standardized data. The polygon view of CT presented for 18 different traits of wheat cultivars showed six vertex cultivars as G3, G4, G5, G9, G11 and G12. The cultivar G4 had the highest values for most of the measured traits. Generally based on vector view, ideal cultivar and ideal tester biplots, it was demonstrated that the selection of high grain yield will be performed via thousand seed weight, spike length and grain diameter. These traits should be considered simultaneously as effective selection criteria evolving high yielding wheat cultivars because of their large contribution to grain yield. The cultivars G3 and G4 could be considered for the developing of desirable progenies in the selection strategy of wheat improvement programmes
Vaccinium Macrocarpon – A new Alien Plant Species in Lithuania
Authors: Gudžinskas Zigmantas , Petrulaitis Lukas , Arlikevičiūtė Lina
Published: July 2014

Gudžinskas Z., Petrulaitis L., Arlikevičiūtė L., 2014: Vaccinium macrocarpon - a new alien plant species in Lithuania [Stambiauogė spanguolė (Vaccinium macrocarpon) - nauja svetimžemė rūšis Lietuvoje]. - Bot. Lith., 20(1): 41-45.

Extensive colonies of V. macrocarpon Aiton were found in 2013 during the investigations of the flora of Rėkyva wetland complex (Šiauliai district) in a cutover and abandoned Piktmiškis peatbog situated in the environs of Rėkyva village. This species was widely distributed on about 31 ha area and solitary individuals or small patches were recorded in various distance from the dense population in bog woodlands. It is supposed that seeds of this species were dispersed by birds. V. macrocarpon should be treated as a naturalized species in Lithuania. Recommendation to use V. macrocarpon for re-cultivation of cutover peatbogs should be considered with caution in order to avoid its probable invasions in natural, disturbed and degraded bog habitats. Notes on cranberry nomenclature and taxonomy are also provided
Batrachium (Ranunculaceae) in the Rivers of Lithuania
Authors: Butkuvienė Jurgita , Sinkevičienė Zofija , Žvingila Donatas
Published: July 2014

Butkuvienė J., Sinkevičienė Z., Žvingila D., 2014: Batrachium (Ranunculaceae) in the rivers of Lithuania [Batrachium (Ranunculaceae) Lietuvos upėse]. - Bot. Lith., 20(1): 46-56.

Batrachium (DC.) S.F.Gray is one of the most complicated taxonomic groups of aquatic plants. Identification to species level often is very difficult because of simplified morphology and variable taxonomic interpretation of the group. This paper reports the results of the revision of herbarium specimens of Batrachium from flowing waters. The occurrence and distribution of Batrachium fluitans and Batrachium pseudofluitans in the rivers of Lithuania are presented as well as morphological characters important for the separation of these taxa are discussed
Louse (Insecta: Phthiraptera) infestations of European Bee-eaters (Merops apiaster Linnaeus, 1758) at Albertirsa, Hungary
Authors: Karáth Kata , Fuisz Tibor István , Vas Zoltán
Published: July 2014

Colonial breeding birds such as the European Bee-eater (Merops apiaster), are perfectly suited for ectoparasitological studies, as their elaborate social life and frequent body-to-body contacts induce high prevalence of louse (Phthiraptera) infestations. In this study we investigated a large breeding colony at Albertirsa, Hungary, and measured the louse burden of the breeding population. With more than 200 pairs nesting in the loess wall there, it may be Hungary’s largest colony of European Bee-eaters. We sampled breeding birds and compared their louse burdens between age groups and sexes. We report the prevalence, mean and median intensity of infestations of the three louse species harboured by the Bee-eaters, and the results of louse burden comparisons between age groups and sexes.