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Rapid assessment of bisphenol A toxicity on fish eggs using optical nanomotion detection
No full textFish have a vital role in environment and human nutrition worldwide. Assessing the health of fish reproductive cells is crucial for both wild populations and aquaculture, serving as a key indicator of ecosystem health and the safety of seafood. Bisphenol A (BPA), a plastic monomer, emerges as an environmental pollutant with toxic effects on aquatic organisms, particularly disrupting reproduction. Traditional biomarkers for sperm and egg quality can be complex and resource-intensive, prompting the need for simpler, rapid testing methods. This study utilizes a nanomotion-based technique to assess the viability of carp (Cyprinus carpio) eggs exposed to BPA. Nanomotion measures cell oscillations, which cease on viability loss. Unfertilized and fertilized carp eggs were exposed to varying BPA concentrations, and x-y motions were recorded. Statistical analyses showed significant changes in unfertilized and fertilized egg nanomotion on BPA exposure, indicating increased cell activity in contaminated samples. The second-order polynomial model characterizes the dose-response of cellular nanomotion to increasing BPA concentrations. The estimation indicates that maximum nanomotion occurs at a BPA concentration of 0.03 mM in both unfertilized and fertilized eggs. According to our knowledge, this study reports for the first time use of an optical nanomotion method for direct assessment of the effect of a pollutant on fish eggs. This method showed that both unfertilized and fertilized eggs are sensitive to BPA exposure. By mimicking natural fertilization conditions, it deepens our understanding of aquatic ecosystems and helps to protect fisheries and global food security. This method offers a simple, rapid, and effective tool for assessing the impact of environmental contaminants on fish reproductive health
The NOVATRODES project: where theory meets application
No full textWith an objective to produce industrially applicable cathodes for alkaline water splitting, the Novatrodes project (Innovative Coated Porous Electrodes for Large Scale Hydrogen Production) aimed to offer solutions to improve the catalytic performance of Nickel-based porous materials.
One approach was to use electrodeposition as a suitable method to coat Ni foams, that are commonly used in zero-gap flow alkaline electrolyzers as electrodes. Electrodeposition was chosen since it is suitable for coating complex 3D porous surfaces in simple setups, offering complete surface coverage while being scalable and cost-effective. In this research we have used various Ni foam substrates with open pore structure, different in pore size, and applied Ni-Sn alloy coatings with demonstrated superior catalytic effect to enhance the performance of Ni foams for hydrogen evolution reaction (HER) [1,2,3]. With a profound theoretical background in electrodeposition and electrocatalysis, we have built our research starting from surface preparation, investigation of the deposition mechanisms, progressing to the optimization of the electrodeposition process, that lead to the scale-up of the samples for single-cell testing under industrial conditions. The detailed electrochemical characterization was conducted in 1M KOH at 30°C for initial assessment of the electrocatalytic activity. After defining the optimal electrodeposition conditions for each substrate used, the optimized electrodes were tested in 30% KOH, at elevated temperatures, providing details on the overpotential dependance on the temperature, achieving remarkable overpotential of only 80 mV at 1 A cm-2 cathodic current density. Lastly, the electrodes were tested in a zero-gap flow electrolyzer significantly outperforming uncoated Ni foams used as cathodes and providing a stable voltage response over 100 hours of operation at 0.5 A cm-2. Samples were analysed regarding their composition and morphology by SEM, TEM, XRD, XPS, and other physicochemical methods, and the results were correlated to the electrochemical characteristics
Comparison of potentially toxic elements (PTEs) and organochlorine pesticides (OCPs) levels in Rutilus rutilus (Linnaeus, 1758) sampled from different reservoirs in terms of human health risk due to consumption
No full textThis study evaluates the potential human health risks of environmental pollutant loads carried
by consumption of roach (Rutilus rutilus, Linnaeus, 1758), a bioindicator of environmental pollution from the Cyprinidae family in freshwater systems. We analyzed the concentrations of 26 potentially toxic elements (PTEs) in the muscle, gills, and liver, and 18 organochlorine pesticides (OCPs) in the muscle of roach originating from reservoirs (artificial lakes) with different uses (power generation and water supply) and anthropogenic impacts. Elemental concentrations were compared to maximum allowable concentrations and used to calculate pollution indices, including the metal pollution index and liver/ muscle Hg index, health risk and benefit indices (target hazard quotient—THQ, target cancer risk—TR, Se:Hg, Na:K, and Ca:Mg ratios), and contributions of
selected trace elements and macronutrients in roach meat. Additionally, the condition factor and histopathology were applied as biomarkers. The results showed that element accumulation varied between sites and tissues, with muscle tissue having the lowest pollution load and gills being the most exposed. OCP concentrations were below the maximum residue levels at all sites. Health risk and benefit indices determined no significant risks from the consumption of roach meat. The biomarker analysis showed diverse results with regard to pollutant accumulation. The highest anthropogenic pressure was observed in reservoirs used for power generation. Additionally, reservoirs at higher elevations were less polluted compared to reservoirs at lower elevations. Overall, the study suggests that the roach is a suitable bioindicator of environmental pollution
Integrating archaeology and materials science: a review of multidisciplinary analysis of bricks from medieval Serbian buildings
No full textThis research review investigates the production technology of medieval Serbian bricks through a multidisciplinary approach combining archaeology and materials science. Conducted over two decades – 1980s and 1990s, the study utilised various analytical methods, including chemical analysis, X-ray diffraction, electron paramagnetic resonance, and differential thermal analysis, to determine the composition, microstructure, and firing conditions of bricks from Serbian monasteries. Results indicate that medieval craftsmen employed controlled firing techniques, using a polymineral raw material mixture and optimising temperature conditions to enhance durability. The findings confirm archaeological theories regarding historical brick-making processes, and provide valuable data for the preservation of cultural heritage. By establishing a methodological framework for analyzing archaeological ceramics, this study contributes to both historical and scientific research. The integration of materials science in archaeology enables a deeper understanding of past technological advancements, supporting further studies in cultural heritage conservation and the history of medieval construction materials
Праћење птица помоћу савременог GSM телеметријског уређаја домаће производње
No full textПраћење заштићених и угрожених врста птица од изузетне је важности јер доноси кључне информације о њиховим кретањима, начину живота и обрасцима понашања, неопходне за праћење броја јединки и очување популације на одређеној територији. Посебан значај има мониторинг јединки реинтродукованих у природу након опоравка, јер се на тај начин процењује успех рехабилитационих програма и услови адаптације у дивљини. У сврху праћења користе се савремени GPS телеметријски уређаји, који се деле на две основне категорије: радио-телеметријске уређаје, намењене праћењу птица чије кретање остаје
углавном унутар ограниченог подручја у околини места гнежђења, и GSM телеметријске уређаје, погодније за праћење врста које прелазе знатно веће удаљености током миграција или тражења повољних станишта. Радио телеметријски уређаји одликују се ниском масом и дужом аутономијом рада на бате-рије, али захтевају посебан радио уређај за очитавање прикупљених података, док GSM уређаји омогућавају пренос података путем мобилне мреже (2G/4G), континуални мониторинг јединки као и мењање параметара уређаја у току рада. Прикупљени теле- метријски подаци користе се за мапирање миграционих рута, идентификацију кључних места гнежђења и анализу избора станишта, чиме се обезбеђује основа за планирање ефективних мера заштите и управљање станишним ресурсима. У оквиру овог рада биће детаљно описана примена GSM телеметријског уређаја домаће фирме Canandi из Ниша, као и преглед функционалности веб портала за централизовано праћење јединки, приказ географских и временских података и подешавање свих релевантнихпараметара уређаја
Manganese assimilation by crops from Gramíneae, Brassicáceaeand Leguminósae (L.) families from Albic Retisols reclaimed with conversion chalk
No full textManganese availability can be a serious limiting factor for plant growth. Trans-location of manganese (Mn) in the tissues of plants from the families Gramíne-ae, Brassicáceae and Leguminósae (L.)was studied on a strongly acidic Albic Re-tisols limed with increasing doses of conversion chalk (CC) in a 5-year pot ex-periment. Studied crops were vetch, rapeseed and barley. Results showed that the transfer of Mn into plants decreases with the increasing dose of CC. There was a correlation between the manganese content in the grain and straw of spring barley (r = 0.96; P < 0.01). The concentration of Mn in the tissues of barley and rapeseed fits into the range capable for ensuring the proper functioning of plants. The doses of conversion chalk above 13.6 t ha–1 led to a decrease in the uptake of Mn by vetch to the lower deficiency threshold. The results imply that the role of Mn for plants is still largely underestimated and requires further study
Hydrogen evolution reaction on electrodeposited Ni-MoOx composite coatings
No full textNi-MoOx composite coatings were electrodeposited under severe hydrodynamic conditions from the suspension containing NH4Cl, NiCl2 and MoOx powder. For the first time in the literature room temperature XRD analysis of as-prepared MoOx powder revealed the presence of different compounds: MoO2.8, H2MoO4, MoO3, MoO2 and (NH4)2Mo2O7. XPS analysis confirmed their presence in the coating: Mo6+and Ni2+species found on the top surface, and Mo4+, Mo5+, Mo6+, Ni2+, Ni0 species detected deeper within the coating. SEM-EDS analysis confirmed that coatings electrodeposited from higher concentrations of MoOx are rougher and contain higher amount of Mo. MoOx particles embedded in the composite coatings were found to be amorphous, only Ni was crystalline (as confirmed by SAED analysis). The HER was investigated in 30 wt. % KOH at 70 ◦C, with the lowest η at j =-500 mA cm-2 amounting to -88 mV for the best Ni-MoOx sample. A modified approach to the analysis of Nyquist plots recorded at different η values enabled determination of the exchange current densities for the charge transfer reaction (jo,ct), intermediate adsorption reaction (jo,ads) and total HER (jo,tot) from the dependences ηcorr vs. log(Rct-1), ηcorr vs. log(Rp-1), ηcorr vs. log(RF-1) and log τ vs. ηcorr. It should be emphasized that jo,tot is not a simple sum of jo,ct and jo,ads since both reactions occur simultaneously and are potential-dependent. The accelerated service life test (ASLT) confirmed the superior performance of the most active Ni-MoOx coating compared to the commercial De Nora cathode
Electrical properties of x(0.75 Na1/2Bi1/2TiO3-0.25SrTiO3)(1-x)PVDF flexible piezoceramic polymer composites
No full textInvestigations of lead-free piezoelectric materials for applications in self-powered devices rapidly increased in the last years. Herein, as lead-free piezoelectric material, we employed a system that contains sodium bismuth titanate and strontium titanate, 0.75Na1/2Bi1/2TiO3-0.25SrTiO3 (NBT-ST), which was prepared by solid-state reaction. Flexible composite films were prepared by mixing this piezoelectric material with polyvinylidene fluoride (PVDF) in different ratios and employing the hot pressing procedure. X-ray analysis confirmed the crystalline structure of the obtained NBT-ST piezoelectric phase. FTIR analysis of the flexible composite films indicated that the transformation of the electro-inactive PVDF α-phase into the electro-active β and γ phases was obtained by hot pressing. Calculated storage energy densities of the investigated films revealed an increasing trend with increasing amount of NBT-ST active phase. The same increasing trend was noticed during the testing by force impact. The highest output voltage was obtained for the samples with the highest amount of piezoelectric active phase. These flexible composite films proved significant capabilities for energy storage application, with storage efficiency up to 61 %. Moreover, the output voltage up to 18 V indicates the potential of these materials for energy harvesting applications
Ferroelectric Materials
No full textThe field of ferroelectric materials is continuously expanding towards new realms
of extraordinary properties and applications. New materials have been synthesized, and
more advanced properties have been obtained, opening the way to more and more cutting-
edge applications. Different methods for the design of new materials through chemical
and epitaxial strain have been employed. Strong progress has also been registered in
the synthesis and characterization of ferroelectric materials with constrained geometries,
like thin film heterostructures and nanomaterials. Epitaxial strain engineering has been
employed to stabilize non-bulk phases in thin films and heterostructures. Potentialities
arising from the coupling of the ferroelectric order parameter with magnetic or elastic order
parameters, such as in multiferroics, have been explored, opening up new application
windows. In this Special Issue, we have collected eight articles (two review papers and six
original research articles) devoted to research on ferroelectric materials in a wide range of
topics: piezoelectric and multiferroic single crystals and ceramics, molecular piezoelectrics,
perovskite epitaxial thin films, flexible piezo-composite thick films, additive manufacturing,
and sustainable “green” synthesis. In the following, we will briefly evidence of some of the
important points in these papers
Silicon mitigates combined pathogen and herbivore stress by affecting leaf nutritional traits and larval performance in oak
No full textThe beneficial role of silicon (Si) in enhancing plant resistance to insect herbivory and pathogen attack
is well established. However, its effectiveness under simultaneous biotic stresses remains less explored.
We developed a tri-trophic model system comprising pedunculate oak (Quercus robur L.), the root
pathogen Phytophthora plurivora T. Jung & T.I. Burgess, and gypsy moth (Lymantria dispar L.) larvae.
Our study aimed to assess the effects of Si supplementation on leaf nutritional traits and larval feeding
behavior and performance. Silicon (+Si) was added as monosilicic acid (H4SiO4) in the amount of 100
mg Si kg−1 dry soil, corresponding to a field application of about 150 kg Si ha−1. Concentrations of
phosphorus (P), boron (B), copper (Cu), iron (Fe), manganese (Mn), zinc (Zn), molybdenum (Mo),
nickel (Ni), potassium (K), calcium (Ca), and magnesium (Mg) in oak leaves and larval midguts were
measured by ICP-MS, while carbon (C), nitrogen (N), and sulfur (S) were determined via CNS
elemental analysis. Larval performance was assessed using standard nutritional parameters: relative
consumption rate (RCR), relative growth rate (RGR), approximate digestibility (AD), and efficiencies
of conversion of ingested and digested food into biomass (ECI and ECD, respectively). Although the
infection by P. plurivora significantly decreased leaf concentrations of P, S, N, Mo, and Ni in −Si plants,
larval performance was enhanced in this treatment, likely due to compensatory feeding and increased
digestibility of weakened leaf tissues. Plant infection overall did not affect element concentrations
(except for Ca and B) in the larval midgut. However, Si supplementation, especially under P.
plurivora infection, significantly increased leaf Si accumulation, resulting in reduced leaf consumption
(lower RCR), assimilation (lower AD), and conversion efficiencies (lower ECI and ECD), ultimately
suppressing larval growth (lower RGR). In the midgut, Si treatment did not significantly affect the
nutrients concentrations (apart from Ca and Ni) when larvae fed on noninfected plants, while, in
contrast, it led to a general decline of nutrients (except S) when they fed on infected plants. Interestingly,
this decline in midgut did not consistently reflect the induced changes in leaves. These results
demonstrate that soil Si application, particularly in the presence of pathogenic infection, can induce not
only the well-established antifeedant effects in leaves, but can also alter herbivore nutrient uptake,
thereby affecting larval performance