bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aquatic Plant Trapa natans L. as Bioindicator of Trace Metal Contamination in a Freshwater Lake (Skadar Lake, Montenegro)
Authors: Petrović Dragana , Jančić Dejan , Furdek Martina , Mikac Nevenka , Krivokapić Slađana 
Published: October 2016

Abstract
Skadar Lake is the largest shallow lake in southeastern Europe. It is located within a national park, and is included in the Ramsar List of international important wetlands, so its preservation and protection from pollution is very important. The aim of this study was to investigate bioaccumulation of the ecotoxic metals Cd, Pb and Cr from sediments of Skadar Lake in the aquatic macrophyte Trapa natans L. Samples of sediment and plants were collected at nine locations covering all major water inputs to the lake as well as locations where contamination could be expected. The obtained results indicate that sediments from the Skadar Lake are only locally contaminated with Cd (0.03–1.18 mg kg−1), generally contaminated with Cr (15.8–180 mg kg−1), the concentrations of both elements frequently exceeding sediment quality guidelines, while concentrations of Pb were low (2.7–17.4 mg kg−1). The highest bioaccumulation of all metals from sediment to Trapa natans L. was observed in the root, with accumulation efficiency decreasing in the order Cd > Cr > Pb. Translocation from root to stem was also higher for Cd than for Cr and Pb, while the translocation from stem to leaf was comparable for all three metals. From the three investigated metals Cd showed the highest mobility. The results indicate that Trapa natans L. may be a very promising bioindicator of trace metal contamination in Skadar Lake.
The Application of Benthic Diatoms in Water Quality Assessment (Mlava River, Serbia)
Authors: Jakovljević Olga S. , Popović Slađana S. , Vidaković Danijela P. , Stojanović Katarina Z. , Krizmanić Jelena Ž. 
Published: October 2016

AbstractThe main objective of this study was to assess the ecological status of the Mlava River based on epilithic diatoms and to test the use of diatom indices as a tool for estimating the quality of flowing waters in Serbia. Quantitative analysis showed that in AprilAchnanthidium minutissimumwas dominant at each site, except at the fifth site, whereAmphora pediculuswas dominant. In July and September,Achnanthidium minutissimum, Achnanthidium pyrenaicum,Amphora pediculus,Denticula tenuis,Diatoma vulgaris,Gomphonema elegantissimum,Cocconeis pseudolineataandCocconeis placentulavar.lineatadominated. Detrended correspondence analysis (DCA) was used to detect the major patterns of variation in species composition. The first DCA axis summarizes the distribution of the diatom community, mainly through temperature, conductivity, oxygen and water hardness gradient. The second DCA axis was weakly correlated with few variables. Based on the average values of the pollution sensitivity index (IPS), commission for economical community metric (CEE) and biological diatom index (IBD), the water of the Mlava River belonged to water class I during all three seasons. Values of the diatom-based eutrophication/pollution index (EPI-D) indicated class II water quality. According to calculated trophic diatom index (TDI) values, water of the Mlava River was characterized by intermediate nutrient concentrations during three seasons. Principal components analysis was used to represent the correlation between diatom indices, and the highest correlation among the selected diatom indices is seen between EPI-D, IPS and IBD.
Dealing with Interpretability Issues in Predicting Firm Growth: Factor Analysis Approach
Authors: Bilandžić Ana , Marina Jeger , Šarlija Nataša 
Published: October 2016

Abstract

Background: Alongside the theoretical progress made in understanding the factors that influence firm growth, many methodological challenges are yet to be overcome. Authors point to the notion of interpretability of growth prediction models as an important prerequisite for further advancement of the field as well as enhancement of models’ practical values.

Objectives: The objective of this study is to demonstrate the application of factor analysis for the purpose of increasing overall interpretability of the logistic regression model. The comprehensive nature of the growth phenomenon implies propensity of input data to be mutually correlated. In such situations, growth prediction models can demonstrate adequate predictability and accuracy, but still lack the clarity and theoretical soundness in their structure.

Methods/Approach: The paper juxtaposes two prediction models: the first one is built using solely the logistic regression procedure, while the second one includes factor analysis prior to development of a logistic regression model.

Results: Factor analysis enables researchers to mitigate inconsistencies and misalignments with a theoretical background in growth prediction models.

Conclusions: Incorporating factor analysis as a step preceding the building of a regression model allows researchers to lessen model interpretability issues and create a model that is easier to understand, explain and apply in real-life business situations.
Biofouling reduction for improvement of depth water filtration. Filter production and testing
Authors: Sztuk - Sikorska Ewa , Gradon Leon 
Published: October 2016

AbstractWater is a strategic material. Recycling is an important component of balancing its use. Deep-bed filtration is an inexpensive purification method and seems to be very effective in spreading water recovery. Good filter designs, such as the fibrous filter, have high separation efficiency, low resistance for the up-flowing fluid and high retention capacity. However, one of the substantial problems of this process is the biofouling of the filter. Biofouling causes clogging and greatly reduces the life of the filter. Therefore, the melt-blown technique was used for the formation of novel antibacterial fibrous filters. Such filters are made of polypropylene composites with zinc oxide and silver nanoparticles on the fiber surface. These components act as inhibitors of bacterial growth in the filter and were tested in laboratory and full scale experiments. Antibacterial/bacteriostatic tests were performed on Petri dishes with E. coli and B. subtilis. Full scale experiments were performed on natural river water, which contained abiotic particles and mutualistic bacteria. The filter performance at industrial scale conditions was measured using a particle counter, a flow cytometer and a confocal microscope. The results of the experiments indicate a significant improvement of the composite filter performance compared to the regular fibrous filter. The differences were mostly due to a reduction in the biofouling effect.
Modification of polypropylene membranes by ion implantation
Authors: Kotra-Konicka Karolina , Kalbarczyk Joanna , Gac Jakub M. 
Published: October 2016

AbstractThe influence of ion implantation on the structure and properties of polymers is a very complex issue. Many physical and chemical processes taking place during ion bombardment must be taken into consideration. The complexity of the process may exert both positive and negative influence on the structure of the material. The goal of this paper is to investigate the influence of H+, He+and Ar+ion implantation on the properties of polypropylene membranes used in filtration processes and in consequence on fouling phenomena. It has appeared that the ion bombardment caused the chemical modification of membranes which has led to decrease of hydrophobicity. The increase of protein adsorption on membrane surface has also been observed.
Determination of technical and economic parameters of an ionic transport membrane air separation unit working in a supercritical power plant
Authors: Kotowicz Janusz , Michalski Sebastian , Balicki Adrian 
Published: October 2016

Abstract
In this paper an air separation unit was analyzed. The unit consisted of: an ionic transport membrane contained in a four-end type module, an air compressor, an expander fed by gas that remains after oxygen separation and heat exchangers which heat the air and recirculated flue gas to the membrane operating temperature (850 °C). The air separation unit works in a power plant with electrical power equal to 600 MW. This power plant additionally consists of: an oxy-type pulverized-fuel boiler, a steam turbine unit and a carbon dioxide capture unit. Life steam parameters are 30 MPa/650 °C and reheated steam parameters are 6 MPa/670 °C. The listed units were analyzed. For constant electrical power of the power plant technical parameters of the air separation unit for two oxygen recovery rate (65% and 95%) were determined. One of such parameters is ionic membrane surface area. In this paper the formulated equation is presented. The remaining technical parameters of the air separation unit are, among others: heat exchange surface area, power of the air compressor, power of the expander and auxiliary power. Using the listed quantities, the economic parameters, such as costs of air separation unit and of individual components were determined. These quantities allowed to determine investment costs of construction of the air separation unit. In addition, they were compared with investment costs for the entire oxy-type power plant.
Dynamics of particle loading in deep-bed filter. Transport, deposition and reentrainment
Authors: Przekop Rafał , Gradoń Leon 
Published: October 2016

Abstract
Deep bed filtration is an effective method of submicron and micron particle removal from the fluid stream. There is an extensive body of literature regarding particle deposition in filters, often using the classical continuum approach. However, the approach is not convenient for studying the influence of particle deposition on filter performance (filtration efficiency, pressure drop) when non-steady state boundary conditions have to be introduced. For the purposes of this work the lattice-Boltzmann model describes fluid dynamics, while the solid particle motion is modeled by the Brownian dynamics. For aggregates the effect of their structure on displacement is taken into account. The possibility of particles rebound from the surface of collector or reentrainment of deposits to fluid stream is calculated by energy balanced oscillatory model derived from adhesion theory. The results show the evolution of filtration efficiency and pressure drop of filters with different internal structure described by the size of pores. The size of resuspended aggregates and volume distribution of deposits in filter were also analyzed. The model enables prediction of dynamic filter behavior. It can be a very useful tool for designing filter structures which optimize maximum lifetime with the acceptable values of filtration efficiency and pressure drop.
Correlation between air flow rate and pollutant concentrations during two-stage oak log combustion in a 25 KW residential boiler
Authors: Juszczak Marek 
Published: October 2016

Abstract
It can be expected that there is a considerable correlation between combustion air flow rate and the concentrations of carbon monoxide, hydrocarbons and nitrogen oxide in the flue gas. The influence of temperature and oxygen concentration in the combustion zone on the concentrations of carbon monoxide, hydrocarbons and nitrogen oxide in the flue gas, for high and low combustion air flow, was analysed. Oxygen concentration for which the concentration of carbon monoxide is the lowest was determined, as well as the mutual relation between carbon monoxide and nitrogen oxide concentration.
Rural Sanctuaries as ‘Smart Destinations’ – Sustainability Concerns (Mazovia Region, Poland)
Authors: Pawlikowska-Piechotka Anna , Gołębieska Karolina , Łukasik Natalia , Ostrowska – Tryzno Anna , Sawicka Karolina 
Published: October 2016

AbstractThe general objective of this paper is to present and discuss the factors that need to be taken into account to ensure that the development and management of religious tourism at rural sites was sustainable from an economic, environmental and socio-cultural point of view. Among other issues, sustainable religious tourism means accessibility to the sanctuaries, protection of cultural and heritage values of the local community, benefits for the local residents and meaningful experience for visitors. Authors were especially interested in the less popular, more remotely located holy sites in Mazovia Region (Poland) and two concerns: readiness to respond the needs of persons with different disabilities and local community opinion on tourists. As was documented by our research outcomes despite the recent numerous improvements, the most popular rural sanctuaries in Mazovia Region, remain only partially accessible for persons with disabilities. As masses of pilgrims have a significant effect on wellbeing and everyday life quality of residents (contributing both to positive and to negative effects), those who accept that tourists are important for economic development, benefit from it, creating ‘smart host area’. These rural communities which are not knowledgeable about positive impacts – see only negative consequences.
Cognitive Impairment in Multiple Sclerosis
Authors: Trenova Anastasiya G. , Slavov Georgi S. , Manova Maria G. , Aksentieva Jana B. , Miteva Lyuba D. , Stanilova Spaska A. 
Published: October 2016

Abstract
Multiple sclerosis (MS) is a socially significant immune-mediated disease, characterized by demyelination, axonal transection and oligodendropathy in the central nervous system. Inflammatory demyelination and neurodegeneration lead to brain atrophy and cognitive deficit in up to 75% of the patients. Cognitive dysfunctions impact significantly patients’ quality of life, independently from the course and phase of the disease.
The relationship between pathological brain findings and cognitive impairment is a subject of intensive research.
Summarizing recent data about prevalence, clinical specificity and treatment of cognitive disorders in MS, this review aims to motivate the necessity of early diagnosis and complex therapeutic approach to these disturbances in order to reduce the social burden of the disease.
Sub-Surface Microwave Imaging Using Four-Slot Vivaldi Antenna with Improved Directivity
Authors: Akhter Zubair , Kumar Pankaj , Akhtar M. Jaleel 
Published: October 2016

Abstract
The conventional tapered slot Vivaldi antenna is well known for its ultra-wide band characteristics with low directivity. To improve the directivity of the conventional Vivaldi antenna, a four-slot Vivaldi antenna (FSVA) is proposed here to operate in the frequency range of 2–11 GHz. For feeding the FSVA, a binomial three-section V-shaped even mode power divider with progressing T-junctions is also designed and tested here, which is then integrated with the antenna. The proposed antenna prototype is designed and fabricated on a 1-mm thick FR-4 substrate (ɛr=4.3, tanδ=0.025), and the return loss and radiation characteristics are investigated in the anechoic environment. The measured result shows a good agreement with the numerical simulation performed using the EM Simulator i. e. CST MWS-2015. It is found that the directivity of FSVA is approximately doubled as compared to that of the conventional Vivaldi antenna having the same dimensions. From the application point of view, the fabricated antenna is used to image various metallic objects hidden inside the sand using a vector network analyzer and associated RF components. The obtained 2D microwave images of the test media successfully show that the hidden objects can effectively be located and detected using the proposed FSVA in conjunction with a simple imaging scheme.
An Efficient, Wideband, CPW-Fed Antenna Based on Simplified Composite Right/Left-Handed Transmission Line
Authors: Li Zhaozhan , Zhou Cheng , Lin Yanhong 
Published: October 2016

Abstract
A wideband electrically small antenna (ESA) based on simplified composite right/left-handed transmission line (SCRLH-TL) is designed, fabricated and tested. The antenna consists of two different sized SCRLH-TL unit cells with different+1st-order mode resonance frequencies. The wideband property of antenna is achieved when these two+1st-order mode resonance frequency suitably merge. A dispersion analysis of the SCRLH-TL reveals that an increase in series of the dual-spiral capacitor would decrease the+1st-order mode resonance frequency, thus reducing the electrical size of the proposed antenna. The 10 dB fractional bandwidth (FBW10 dB) was 54.5 % and the measured maximum was 96.2 %, with an electrical size of 0.32λ0×0.16λ0×0.015λ0 at 3.0 GHz (where λ0 is the wavelength in vacuum). It is shown that the numerical results closely fit the measured results.
Novel High-Gain Circularly Polarized Lens Antenna Using Single-Layer Transmissive Metasurface
Authors: Zhuang Yaqiang , Wang Guangming , Li Haipeng , Guo Wenlong 
Published: October 2016

Abstract
A high-gain lens antenna employing single-layer focusing metasurface (MS) is proposed in this article. The single-layer element achieves a 360° transmission phase range with a transmission magnitude better than 0.9. And the focusing MS consists of 169 elements was designed by utilizing the technique of varying rotation angle to compensate the phase delay. Thus, a lens antenna is constructed by placing a circularly polarized (CP) patch antenna at the focal point of the MS. The fabricated lens antenna demonstrates a good performance of 4.6 % 3-dB axial ratio bandwidth and 6 % 1-dB gain bandwidth, respectively. Moreover, the maximum gain is 18.3 dBic at 15 GHz, which is enhanced by 11.4 dBic compared with the patch antenna. Due to the single-layer structure, this design has a low profile and easy fabrication process compared with the conventional designs, making it an attractive alternative to compact high-gain antenna.
Influence of Peroral Supplementation of Selenium and Vitamin E on the Antioxidant Status of Racing Pigeons
Authors: Vargová V. , Zigo F. , Chripková M. , Toropilová D. , Tomko M. 
Published: October 2016

Abstract
The racing season is considered a critical period for racing pigeons due to the susceptibility to stress and weakening of the birds. One of the ways how to support their health and avoid problems involves supplementation of mineral-vitamin preparations based on selenium and vitamin E, which act as important antioxidants and protect cells against damage. This study investigated the influence of peroral supplementation of selenium at a dose of 0.3 mg Se.kg−1 feed dry matter (DM) in the form of Na2SeO3 and vitamin E 300 mg.ml−1 added to water at a rate of 4 ml.l−1 during 60 days. The supplemented group comprised 14 pigeons and their results were compared with a control group of 14 pigeons fed non-supplemented commercial feed. Blood samples were collected and examined at the beginning of the supplementation period, one day before a 300 km race and after the race. Pigeons from the supplemented group exhibited increased plasma levels of Se and vitamin E, as well as the activity of glutathione peroxidase (GSH-Px) before and after the 300 km race in comparison with the controls. Comparison of the activity of the enzymes: alanine aminotransferase (ALT), aspartate aminotransferase (ASP), alkaline phosphatase (ALP), and creatinine kinase (CK) at the beginning of the supplementation and one day before the race showed no changes. A significant (P < 0.05) increase in the activity of all investigated enzymes were observed after the race in both groups.
Epizootiological Study of the Occurrence of Canine Babesiosisin Southwestern Slovakia
Authors: Řeháčková K. , Haláková M. , Víchová B. , Kočišová A. 
Published: October 2016

Abstract
This epizootiological study was carried out to investigate the occurrence of canine babesiosis in southwestern Slovakia. The study focused on the proportion of the species of ticks serving as babesia vectors of babesiosis in the ticks collected from selected locations close to Komárno, in southwestern Slovakia. Additionally, observations were made on the health and overall clinical signs in dogs suspected of having babesiosis. In 2014 we collected ticks from vegetation by the drag cloth (flagging) method and also directly from dogs. A totally of 622 ticks were collected: 491 Dermacentor reticulatus and 131 Ix-odes ricinus. Representative samples of ticks (n = 103) were examined by the molecular method and the presence of Babesia spp. DNA was identified in 12.5 % of the Ixodes ricinus ticks collected by flagging and in 9.5 % of the Ixodes ricinus ticks collected from the dogs. Babesia canis (KU681325) with 90 bp sequence, 100 % identical with Babesia canis isolates from dogs for example from: Turkey (KF499115), Rumania (HQ662634), Croatia (FJ209025), Poland (EU622792) and Russia (AY962186), was confirmed after sequencing in one Ixodes ricinus female obtained from a dog. This was the first confirmation of the occurrence of B. canis in Ixodes ricinus ticks in Slovakia. In 2.2 % of the Dermacentor reticulatus ticks obtained from vegetation by flagging, we were able to diagnose the DNA of Babesia canis. In 4.8 % of the Dermacentor reticulatus ticks collected from dogs, the presence of Babesia spp. was confirmed. Thirty three dogs with suspicion of babesiosis were observed in an ambulance by their health and clinical signs. The loss of appetite was observed in 22 patients (66.7 %), apathy in 19 cases (57.6 %), and fever in 19 cases. Closer specification indicating babesiosis was finding engorged ticks on the dog bodies which occurred in 21 cases (63.6 %), haematuria in 8 cases (24.2 %), anaemia in 4 cases (12.1 %), and tremor in 6 cases (18.2 %). Other non-specific signs, such as diarrhoea, vomitus, slowed-down movement, ataxia and lacrimation were also observed in less than 18 % of the examined dogs. On the basis of the specific clinical signs, blood was withdrawn from 33 dogs for preparation of blood smears and in 19 of them (57.6 %) babesia in erythrocytes were confirmed microscopically.
A Study of Fish Lice (Argulus Sp.) Infection in Freshwater Food Fish
Authors: Aalberg K. , Koščová L. , Šmiga Ľ. , Košuth P. , Koščo J. , Oros M. , Barčák D. , Lazar P. 
Published: October 2016

AbstractArgulussp., commonly referred to as fish lice, are crustacean ectoparasites of fishes. The hematophagous parasites attach to and feed off the integument of their hosts. Outbreaks of epizootics have been reported worldwide, causing mass mortalities and having serious economic implications for fish farms and culture efforts.Argulusfish lice may also serve as vectors of infectious diseases and as intermediate hosts of other parasites. Two native European species,A. foliaceusandA. coregoni, as well as the invasive Japanese fish louseA. japonicus,have previously been recorded in Slovakia. This study investigated samples collected at fish farms and culture sites of Common carp (Cyprinus carpioL.), Pike-perch (Sander luciopercaL.) and Brook trout (Salvelinus fontinalisM.) in Eastern Slovakia, as well as samples collected from live fish imported to the Slovak Republic. A quantitative description of the ofArgulussp. was recorded from each locality. Samples from Common carp were identified as the invasiveA. japonicus, and samples from Pike-perch and Brook trout were identified asA. foliaceus. Evidence of a mixed infection of Pike-perch with bothA. foliaceusandA. japonicuswas found in samples from Zemplínska Šírava, which was substantiated by electron microscopic examination. Morphometric characteristics were measured and averages and ranges produced for each species and sex.