Zooplankton of the Butoniga Reservoir

Istraživanje zooplanktona akumulacije Butoniga provedeno je u razdoblju od travnja do listopada 2009. godine, a fizikalno-kemijska analiza vode provedena je u razdoblju od lipnja do listopada 2009. godine kao samostalno istraživanje u svrhu izrade diplomskog rada. Utvrđeno je 7 vrsta slatkovodnih Crustacea, od čega 5 iz skupine Cladocera i 2 iz skupine Copepoda. Zaključeno je da brojnost zooplanktona ovisi o razdoblju istraživanja i dubini jezera. Najveća gustoća zooplanktona zabilježena je u travnju, što je u skladu s proljetnim naglim bujanjem planktona. Najmanja gustoća zooplanktona zabilježena je u listopadu. Vrijednost trofičkog indeksa (TSI) akumulacije iznosila je od 40 do 47,98. Tijekom cijelog razdoblja istraživanja dominiraju „učinkoviti“ mikrofiltratori. Prevladava vrsta Daphnia sp. Obzirom na indeks stupnja trofije, brojnost i sastav zooplanktona, akumulacija Butoniga je mezotrofnog stupnja.Research on zooplankton of the Butoniga Reservoir, was conducted from April to October in 2009., and physico-chemical parametars were analysed from June to October in 2009. A total of 7 species of freshwater Crustaceans (5 Cladocera and 2 Copepoda) was determined. Maximal zooplankton abundance was in April, minimum abundance of zooplankton was in October. TSI of Butoniga Reservoir was between 40 - 47,98. Crustacean zooplankton varied spatially and temporally. Dominant trophic group was “efficient” microfilterfeeders represented by Daphnia sp. According to TSI and zooplankton community structure Butoniga Reservoir is mesotrophic system

Zooplankton of the Butoniga Reservoir

Istraživanje zooplanktona akumulacije Butoniga provedeno je u razdoblju od travnja do listopada 2009. godine, a fizikalno-kemijska analiza vode provedena je u razdoblju od lipnja do listopada 2009. godine kao samostalno istraživanje u svrhu izrade diplomskog rada. Utvrđeno je 7 vrsta slatkovodnih Crustacea, od čega 5 iz skupine Cladocera i 2 iz skupine Copepoda. Zaključeno je da brojnost zooplanktona ovisi o razdoblju istraživanja i dubini jezera. Najveća gustoća zooplanktona zabilježena je u travnju, što je u skladu s proljetnim naglim bujanjem planktona. Najmanja gustoća zooplanktona zabilježena je u listopadu. Vrijednost trofičkog indeksa (TSI) akumulacije iznosila je od 40 do 47,98. Tijekom cijelog razdoblja istraživanja dominiraju „učinkoviti“ mikrofiltratori. Prevladava vrsta Daphnia sp. Obzirom na indeks stupnja trofije, brojnost i sastav zooplanktona, akumulacija Butoniga je mezotrofnog stupnja.Research on zooplankton of the Butoniga Reservoir, was conducted from April to October in 2009., and physico-chemical parametars were analysed from June to October in 2009. A total of 7 species of freshwater Crustaceans (5 Cladocera and 2 Copepoda) was determined. Maximal zooplankton abundance was in April, minimum abundance of zooplankton was in October. TSI of Butoniga Reservoir was between 40 - 47,98. Crustacean zooplankton varied spatially and temporally. Dominant trophic group was “efficient” microfilterfeeders represented by Daphnia sp. According to TSI and zooplankton community structure Butoniga Reservoir is mesotrophic system

Hybrid Stem Intervention as New Post-Pandemic Approach to Motivate Students to Stem

There has long been a struggle over how to increase student interest in careers in STEM and meet the labour market’s need for specialised knowledge and skills. The long-standing debate at the EU level about the role of formal, informal, and non-formal education in meeting these challenges has not yet reached a clear conclusion. In the last decade, there has been a significant increase in the number of STEM programmes offered by various non-governmental organisations in Croatia. These interventions are often localised and have limited social impact, but there is a strong willingness to create an environment for their greater inclusion in the formal education system, triggered by comprehensive curriculum reform in Croatia. Motivation, especially intrinsic motivation, is a crucial driving force in our lives. In our pilot study, conducted with 6th grade elementary students, we aimed to explore the extent to which STEM interventions encourage students to learn more about the topic and whether it is possible to incorporate lessons learned from the pandemic into the design of future interventions. Our results show that there is no significant difference in student motivation after a 45-minute whole-class interactive intervention between face-to-face and virtual delivery. Although the intervention was entertaining, students perceived the science as interesting and useful rather than entertaining. Considering that students have positive attitudes toward Nature as a school subject, an early intervention with students at this age could be useful in maintaining their interest and preventing a decline in interest later in life. This finding is particularly important in the context of the transformation of the Croatian elementary school system into a “whole-day school”, which provides room for incorporating this type of intervention into a regular school system

A recently discovered albino seedling mutant in maize

A lethal albino seedling mutant of maize that is resistant to imazethapyr was found in the material from the Maize Research Institute, Zemun Polje, gene bank, The mutation was characterized by a normal development of the first two leaves, with white coloration appearing from the third to the fifth leaves, at the base of the leaves spreading towards their end, resulting in the death of the whole plant. While the upper leaves were dying, the first two were still green for eight to ten days. It seemed that the mutation was conditioned by one recessive allele

Agronomska, biohemijska i genetička svojstva populacija kukuruza visokog kvaliteta proteina iz banke gena

Nutritional quality of maize is low because maize protein is poor in several essential amino acids. The purpose of this research was to analyze agronomic traits and kernel biochemical and physical properties of 16 gene bank accessions which comprise a mini-core collection for grain quality and to identify populations for improving protein quality. Standard ZP341 hybrid was superior for half of agronomic traits tested, especially grain yield, which was higher from 24% to six times. Ten accessions had protein content over 14 % and were further analyzed for amino acid composition and kernel characteristics. Additionally, genetic relationships between the accessions were determined by Simple Sequence Repeats (SSRs) analysis with 30 primers. All accessions showed elevated contents of most essential amino acids. Population L492 with 1.87 and 0.68 g 100g-1dry weight had the highest contents of leucine and phenylalanine, respectively, but also higher contents of most other analyzed amino acids (p<0.05). Cluster analysis based on SSRs also distinguished L492 by separating it from all other accessions. Compared to ZP341, accessions were significantly inferior in grain weight and dimensions (p<0.05), but superior in most hardness parameters (p<0.05). Pearson correlations revealed lack of negative correlations between biochemical traits, indicating a possibility for concurrent improvement of several amino acids. The best way of improving protein quality of elite materials is through backcrossing and as populations were chosen according to their good general combining ability (with IoDent, Lancaster and BSSS), they could serve for improvement of elite materials of these genetic origins.Nutritivna vrednost kukuruza je niska zbog nedostatka nekoliko esencijalnih amino kiselina. Cilj ovog rada jebio da se analiziraju agronomske osobine, sadržaj proteina i amino kiselina kao i fiziĉka svojstva zrna 16 uzoraka iz banke gena koji ĉine mini coreza kvalitet, da bi se identifikovale populacije za poboljšanje kvaliteta proteina kukuruza. Hibrid ZP 341 (standard) je bio superioran za većinu testiranih agronomskih svojstava, sa prinosom zrna većim za 24% do 600%. Deset uzoraka kod kojih je sadržaj proteina bio veći od 14% je analizirano na sadržaj aminokiselina i karakteristike zrna. TakoĊe su utvrĊeni genetiĉki odnosi izmeĊu uzoraka pomoću 30 SSR markera. Svi uzorci su pokazali povećan sadržaj većine esencijalnih amino kiselina. Populacija L492 je imala najveći sadržaj leucina (1.87g 100g-1suve mase) i fenilalanina (0.68g 100g-1suve mase), ali i veće sadržaje ostalih aminokiselina (p<0.05) u odnosu na ZP341 i analizirane populacije. Klaster analiza zasnovana na SSR markerima je takoĊe izdvojila populaciju L492 od svih ostalih populacija. U odnosu na ZP 341, populacije iz banke gena su bile inferiorne u masi i dimenzijama zrna (p<0.05), ali superiorne u većini parametara tvrdoće zrna (p<0.05). Pirsonove korelacije su pokazale nedostatak negativnih korelacija izmeĊu analiziranih biohemijskih svojstava, što ukazuje na mogućnost poboljšanja kukuruza na više amino kiselina istovremeno. Najbolji naĉin poboljšanja kvaliteta proteina elitnog materijala je putem povratnih ukrštanja, a kako su populacije izabrane prema svojim dobrim opštim kombinacionim sposobnostima (sa IoDent, Lancaster i BSSS), mogle bi da služe za poboljšanje elitnog materijala navedenih heterotiĉnih grupa

Novi podtip cmsS kod kukuruza?

In gene-bank maize collection of Maize Research Institute Zemun Polje (MRI) two samples with untypical mtDNA profile for cytoplasmic male sterility (cms) were identified. These two samples showed typical multiplex polymerase chain reaction (PCR) band for cms-S, but also an additional band of unknown nature. It is assumed that the additional band is the result of a rearrangement of the two mitochondrial episomes characteristic for the cms-S in maize or a duplication of the part of cms-S mitochondrial genome. Additional field and laboratory experiments are necessary in the further lightening of this phenomenon.U banci gena kukuruza (Zea mays L.) Instituta za kukuruz Zemun Polje otkrivena su dva uzorka koja sadrže netipičan mitohondirjalni genom koji uzrokuje citoplazmatičku mušku sterilnost (cms). Ova dva genotipa pokazuju tipičnu multipleks polymerase chain reaction (PCR) traku za S-tip citoplazme, ali i dodatnu traku, čije je poreklo za sada nepoznato. Smatra se da je ona proizvod ili rearanžiranja dva mitohondrijalna epizoma karakteristična za cmsS kukuruza ili do sada još nesekvencioniranih gena koji uzrokuju cms. Za dodatnu potvrdu da je ovo zaista nov fenomen, uradili smo analizu svih poznatih izvora cmsS zajedno sa ova dva uzorka. Nijedan od analiziranih podtipova nije pokazao dodatnu traku koja je nađena u našim uzorcima. Dodatna poljska i laboratorijska istraživanja neophodna su u daljem razjašnjavanju ovog fenomena

The Revolving Door of Adenovirus Cell Entry: Not All Pathways Are Equal

Adenoviruses represent exceptional candidates for wide-ranging therapeutic applications, from vectors for gene therapy to oncolytics for cancer treatments. The first ever commercial gene therapy medicine was based on a recombinant adenovirus vector, while most recently, adenoviral vectors have proven critical as vaccine platforms in effectively controlling the global coronavirus pandemic. Here, we discuss factors involved in adenovirus cell binding, entry, and trafficking ; how they influence efficiency of adenovirus-based vectors ; and how they can be manipulated to enhance efficacy of genetically modified adenoviral variants. We focus particularly on endocytosis and how different adenovirus serotypes employ different endocytic pathways to gain cell entry, and thus, have different intracellular trafficking pathways that subsequently trigger different host antiviral responses. In the context of gene therapy, the final goal of the adenovirus vector is to efficiently deliver therapeutic transgenes into the target cell nucleus, thus allowing its functional expression. Aberrant or inefficient endocytosis can impede this goal, therefore, it should be considered when designing and constructing adenovirus-based vectors

Impact of the Histidine‐Triazole and Tryptophan‐Pyrene Exchange in the WHW Peptide: Cu(II) Binding, DNA/RNA Interactions and Bioactivity

n three novel peptidoids based on the tryptophan—histidine— tryptophan (WHW) pep‐ tide, the central histidine was replaced by Ala‐(triazole), and two derivatives also had one trypto‐ phan replaced with pyrene‐alkyls of different lengths and flexibility. Pyrene analogues show strong fluorescence at 480–500 nm, attributed to intramolecular exciplex formation with trypto‐ phan. All three peptidoids bind Cu2+ cation in water with strong affinity, with Trp‐ Ala‐(triazole)‐Trp binding comparably to the parent WHW, and the pyrene analogues even stronger, demonstrating that replacement of histidine with triazole in peptides does not hamper Cu2+ coordination. The studied peptidoids strongly bind to ds‐DNA and ds‐RNA, whereby their complexes with Cu2+ exhibit distinctively different interactions in comparison to metal‐free ana‐ logues, particularly in the stabilization of ds‐DNA against thermal denaturation. The pyrene pep‐ tidoids efficiently enter living cells with no apparent cytotoxic effect, whereby their red‐shifted emission compared to the parent pyrene allows intracellular confocal microscopy imaging, show‐ ing accumulation in cytoplasmic organelles. However, irradiation with 350 nm light resulted in evident antiproliferative effect on cells treated with micromolar concentrations of the pyrene ana‐ logues, presumably attributed to pyrene‐induced production of singlet oxygen and consecutive cellular damage

DNA Methylome Distinguishes Head and Neck Cancer from Potentially Malignant Oral Lesions and Healthy Oral Mucosa

There is a strong need to find new, good biomarkers of head and neck squamous cell carcinoma (HNSCC) because of the bad prognoses and high mortality rates. The aim of this study was to identify the potential biomarkers in HNSCC that have differences in their DNA methylome and potentially premalignant oral lesions, in comparison to healthy oral mucosa. In this study, 32 oral samples were tested: nine healthy oral mucosae, 13 HNSCC, and 10 oral lesions for DNA methylation by the Infinium MethylationEPIC BeadChip. Our findings showed that a panel of genes significantly hypermethylated in their promoters or specific sites in HNSCC samples in comparison to healthy oral samples, which are mainly oncogenes, receptor, and transcription factor genes, or genes included in cell cycle, transformation, apoptosis, and autophagy. A group of hypomethylated genes in HNSCC, in comparison to healthy oral mucosa, are mainly involved in the host immune response and transcriptional regulation. The results also showed significant differences in gene methylation between HNSCC and potentially premalignant oral lesions, as well as differently methylated genes that discriminate between oral lesions and healthy mucosa. The given methylation panels point to novel potential biomarkers for early diagnostics of HNSCC, as well as potentially premalignant oral lesions