Kinetika sušenja i analiza skupljanja biomaterijala korenja Valeriana officinalis

Drying kinetics and shrinkage of valerian plant root (Valeriana officinalis) was investigated during the convective hot air dryer with forced convection mode. Whole root without cutting, root cut into quarters, and root cut into 2 mm thin slices were used in drying experiments. Initial moisture content of roots was 51.2±0.3% and roots were considered to be dry when they lost 68% of the fresh weight and reached the moisture content of 10%. Drying air temperature was set to be 40 and 50°C, air velocity at 1 m/s. The relative humidity of drying air was not controlled and it depended on surroundings. The experimental results were fitted to the five thin layer drying models and according to the non-linear regression analysis Page model was most suitable to describe the drying kinetics. The characteristic drying curves were created for each experimental set and they showed that the samples' preparation strongly influenced the drying process and drying time. Experiments to determine shrinkage of different cell structures of valerian root were carried out for raw material, as well as for dried samples, by using optical and electron microscopy observations and measurements. It was observed that shrinkage processes are significantly dependent of the type of cell tissue and drying air temperature.Istraživanje kinetike sušenja i analiza skupljanja biomaterijala korenja lekovitog bilja Valeriana officinalis izvršeno je na konvektivnoj sušari sa vrućim vazduhom kao agensom sušenja. U eksperimentima su korišćeni uzorci: ceo koren, koren sečen na četvrtine i koren sečen na uzorke debljine 2 mm. Početni sadržaj vlage u uzorcima iznosio je 51.2±0.3%, a uzorak se smatrao suvim onda kada sadržaj vlage opadne na 10%. Temperatura vazduha u sušari iznosila je 40 i 50oC, sa brzinom strujanja od 1 m/s. Relativna vlažnost vazduha koji dospeva na materijal nije kontrolisana i zavisila je od spoljnih uslova. Eksperimentalni rezultati su analizirani kroz pet najčešće korišćenih modela za opisivanje promene bezdimenzionog sadržaja vlage u vremenu kod sušenja u tankom sloju, pri čemu je ustanovljeno da se kinetika sušenja najbolje opisuje modelom Page-a. Postupcima optičke i elektronske mikroskopije izvršeno je posmatranje uzoraka svežeg i osušenog korenja pri različitim režimima sušenja u cilju praćenja skupljanja materijala. Ustanovljeno je da proces skupljanja bitno zavisi od vrste ćelijskog tkiva u posmatranom poprečnom preseku materijala i od temperaturnog režima sušenja

SOLAR - softver za filtriranje, obradu i vizuelizaciju prikupljenih meteoroloških podataka

The current standards for solar components and systems testing (SRB, EN, ISO, DIN, etc.) imply the determination of the system relevant parameters at the monitored locality. In this regard, it is necessary to prepare all the input data for the selected location in order to determine the standard values, such as: thermal collector performance, factor changes in incident angle of radiation, heat capacity, pressure values and various quality tests. The parameters collected with appropriate measuring instruments are necessary for defining the state of atmospheric moisture air (temperature, relative humidity), air movement (speed and wind direction), ambient characteristic at given location (clouds, precipitation, etc.) and parameters that describe the energetic potential of the Sun (total, direct and diffusion radiation). A software tool for meteorological data processing (SOLAR) is designed and constructed so that the collected data of experimental measurements can be effectively and easily processed, with the possibility to present the results in a number of ways. The basic software components are subroutines for data filtering (extracting the minimum, maximum and average values in the selected time interval of observation), data processing (calculation of unknown characteristic values that are based on experimentally measured values), and visualization of results (graphical representation results).Aktuelni standardi za ispitivanje solarnih komponenata i sistema (SRB, EN, ISO, DIN i drugi) podrazumevaju određivanje svih relevantnih parametara rada instalacije na posmatranom lokalitetu. S tim u vezi, neophodno je pripremiti sve ulazne podatke za odabranu lokaciju radi određivanja standardom definisanih veličina, kao što su: toplotni učinak kolektor, faktor promene upadnog ugla zračenja, toplotnog kapaciteta, padova pritisaka i raznih testova kvaliteta. Veličine koje su od značaja za proračun se mere odgovarajućim mernim instrumentima i neophodne su za definisanje stanja vlažnog atmosferskog vazduha (temperatura, relativna vlažnost), kretanja vazduha (brzina i pravac strujanja vetra), ambijentalnih karakteristika atmosfere na posmatranoj lokaciji (oblačnost, količina padavina, i slično) kao i veličina koje oslikavaju energetski potencijal Sunca na posmatranoj lokaciji (ukupno, direktno i difuzno zračenje). Softver za filtriranje, obradu i vizuelizaciju prikupljenih meteoroloških podataka - SOLAR, osmišljen je i izrađen tako da prikupljene podatke eksperimentalnih merenja efikasno i jednostavno procesuira, a dobijene rezultate potom predstavi korisniku. Osnovne komponente softvera su subrutine za filtriranje podataka (izdvajanje minimalnih, maksimalnih i prosečnih vrednosti u željenom vremenskom intervalu posmatranja), za obradu podataka (izračunavanje nepoznatih karakterističnih veličina koje su od značaja za posmatrani proces na osnovu eksperimentalno merenih veličina) i vizuelizaciju rezultata (grafičko predstavljanje rezultata sa mogućnošću uporednog prikazivanja srodnih veličina i mogućnošću eksportovanja u druge formate pogodne za dalju analizu)

Method for the determination of triclopyr residues in soil

In this study, a method for the determination of triclopyr in soil samples has been developed. The analyte was extracted with acidified acetonitrile, while the determination and quantification of triclopyr were performed by high-performance liquid chromatography (HPLC) with a diode array detection. Optimal HPLC-DAD conditions were: mobile phase acetonitrile and 0.1% H3PO4 (50:50), the flow rate of 0.9 ml/min, and 220 nm of wavelength. In terms of method validation, accuracy (expressed as recovery), linearity, precision (RSD) and LOQ were determined. Obtained results for the recovery using this method, at the three spiking levels, were 81-93%. Precision, expressed as RSD, was 9.1%, while the LOQ was 0.01 mg/kg. Therefore, it can be concluded that the proposed method could be applied for the analysis of triclopyr residues in the soil samples

Софтвер за филтрирање, обраду и визуелизацију прикупљених метеоролошких података

The current standards for solar components and systems testing (SRB, EN, ISO, DIN, etc.) imply the determination of the system relevant parameters at the monitored locality. In this regard, it is necessary to prepare all the input data for the selected location in order to determine the standard values, such as: thermal collector performance, factor changes in incident angle of radiation, heat capacity, pressure values and various quality tests. The parameters collected with appropriate measuring instruments are necessary for defining the state of atmospheric moisture air (temperature, relative humidity), air movement (speed and wind direction), ambient characteristic at given location (clouds, precipitation, etc.) and parameters that describe the energetic potential of the Sun (total, direct and diffusion radiation). А software tool for meteorological data processing (SOLAR) is designed and constructed so that the collected data of experimental measurements can be effectively and easily processed, with the possibility to present the results in a number of ways. The basic software components are subroutines for data filtering (extracting the minimum, maximum and average values in the selected time interval of observation), data processing (calculation of unknown characteristic values that are based on experimentally measured values), and visualization of results (graphical representation results)

Фотодиелектрична карактеризација светлосног погона Au/TiO2 наномотори у течном медију

This article reports on photodielectric properties of hydrocolloids of TiO2 particles and Au/TiO2 hybrid particles of lateral dimension of ∼200 nm. Illumination of the colloids with visible light did not cause measurable changes in their electrical conductivity, while the application of UV (365 nm) light led to photoinduced increase in conductivity of up to 2%. The photogeneration of ions in water, regardless of the presence of the particles, makes a dominant contribution to the photoinduced increase in conductivity of the colloid

Genetic Diversity and Population Structure of Serbian Barley (Hordeum vulgare L.) Collection during a 40-Year Long Breeding Period

Determination of genetic diversity and population structure of breeding material is an important prerequisite for discovering novel and valuable alleles aimed at crop improvement. This study's main objective was to characterize genetic diversity and population structure of a collection representing a 40-year long historical period of barley (Hordeum vulgare L.) breeding, using microsatellites, pedigree, and phenotypic data. The set of 90 barley genotypes was phenotyped during three growing seasons and genotyped with 338 polymorphic alleles. The indicators of genetic diversity showed differentiation changes throughout the breeding periods. The population structure discriminated the breeding material into three distinctive groups. The principal coordinate analysis grouped the genotypes according to their growth habit and row type. An analysis of phenotypic variance (ANOVA) showed that almost all investigated traits varied significantly between row types, seasons, and breeding periods. A positive effect on yield progress during the 40-year long breeding period could be partly attributed to breeding for shorter plants, which reduced lodging and thus provided higher yield stability. The breeding material revealed a considerable diversity level based on microsatellite and phenotypic data without a tendency of genetic erosion throughout the breeding history and implied dynamic changes in genetic backgrounds, providing a great gene pool suitable for further barley improvement

Differential gene expression analysis of heterotic groups’ maize inbred lines under optimal conditions led to the identification of specific gene regulation under low-temperature

Finding new ways of improving crop quality, yield potential and abiotic stress tolerance are some of the most important pursuits in crop production today. As one of the biggest causes of yield and productivity reduction is climate change, specifically increasing temperatures and drought during the summer, a large number of strategies is focussed on lessening their negative effects. Cropping pattern changes include earlier sowing (early spring), when the temperatures are lower, as one of the most promising escape strategies for avoiding high summer temperatures. Thus, development of cold tolerant maize lines became an important goal. Comparative analysis of 46 maize inbred lines belonging to two different genetic backgrounds, one predominantly cold tolerante (marked as Non-Lancaster) and the other predominantly cold sensitive (marked as Lancaster) in the field, was done by whole transriptome sequencing and differential gene expression (DGE) analysis. Plants were grown under optimal, greenhouse conditions and sampled after completing the V4 growth stage. Total RNA isolated from leaves of three plants per inbred line was used for cDNA library preparation by Illumina TruSeq Stranded RNA LT kit. Pair-end sequencing was performed on MiSeq Illumina sequencer using MiSeq Reagent kit, v2 (2 x 150bp). Data manipulation and analysis was performed using a custom-made bioinformatics pipeline that included high throughput sequence data quality control (using FastQC), removal of low quality reads (using Trimmomatic tool, version 0.32), transcriptome assembly and mapping (using Cufflinks, version 2.2.1), expression quantification (using CuffDiff) and DGE analysis (using BLAST2GO and GO analysis Toolkit and Database for Agricultural Community, agriGO v2). DGE analysis revealed 77 differentially expressed genes (DEGs) between the Lancaster and the Non-Lancaster group, 21 of which were statistically supported for differential expression between the two groups and annotated as involved in abiotic stress responses in maize and other plant species. To test DEGs response to cold stress expression of a subset of seven DEGs in eight inbred lines (4 belonging to Lancaster and 4 belonging to Non-Lancaster genetic background) was analyzed under 24h long exposure to low temperatures (6/4° C, 12h photoperiod), with sampling being done 6h and 24h after beginning of the treatment, as well as after 48h of recovery. Six DEGs showed different expression regulation dependent on cold exposure duration and genetic background. These findings imply differently regulated processes between the analysed Lancaster and Non-Lancaster inbred lines, contributing to their different cold response and adaptation, and will be further used for the development of cold tolerant hybrids

Differential gene expression analysis of heterotic groups’ maize inbred lines under optimal conditions led to the identification of specific gene regulation under low-temperature

Finding new ways of improving crop quality, yield potential and abiotic stress tolerance are some of the most important pursuits in crop production today. As one of the biggest causes of yield and productivity reduction is climate change, specifically increasing temperatures and drought during the summer, a large number of strategies is focussed on lessening their negative effects. Cropping pattern changes include earlier sowing (early spring), when the temperatures are lower, as one of the most promising escape strategies for avoiding high summer temperatures. Thus, development of cold tolerant maize lines became an important goal. Comparative analysis of 46 maize inbred lines belonging to two different genetic backgrounds, one predominantly cold tolerante (marked as Non-Lancaster) and the other predominantly cold sensitive (marked as Lancaster) in the field, was done by whole transriptome sequencing and differential gene expression (DGE) analysis. Plants were grown under optimal, greenhouse conditions and sampled after completing the V4 growth stage. Total RNA isolated from leaves of three plants per inbred line was used for cDNA library preparation by Illumina TruSeq Stranded RNA LT kit. Pair-end sequencing was performed on MiSeq Illumina sequencer using MiSeq Reagent kit, v2 (2 x 150bp). Data manipulation and analysis was performed using a custom-made bioinformatics pipeline that included high throughput sequence data quality control (using FastQC), removal of low quality reads (using Trimmomatic tool, version 0.32), transcriptome assembly and mapping (using Cufflinks, version 2.2.1), expression quantification (using CuffDiff) and DGE analysis (using BLAST2GO and GO analysis Toolkit and Database for Agricultural Community, agriGO v2). DGE analysis revealed 77 differentially expressed genes (DEGs) between the Lancaster and the Non-Lancaster group, 21 of which were statistically supported for differential expression between the two groups and annotated as involved in abiotic stress responses in maize and other plant species. To test DEGs response to cold stress expression of a subset of seven DEGs in eight inbred lines (4 belonging to Lancaster and 4 belonging to Non-Lancaster genetic background) was analyzed under 24h long exposure to low temperatures (6/4° C, 12h photoperiod), with sampling being done 6h and 24h after beginning of the treatment, as well as after 48h of recovery. Six DEGs showed different expression regulation dependent on cold exposure duration and genetic background. These findings imply differently regulated processes between the analysed Lancaster and Non-Lancaster inbred lines, contributing to their different cold response and adaptation, and will be further used for the development of cold tolerant hybrids.Book of Abstracts: Belgrade BioInformatics Conference 202

Several genes involved in low temperature response in maize follow different expression patterns at different developmental stages

Earlier sowing is one of the most important strategies of ensuring good yield potential and crop quality under poor environmental conditions arising as consequences of climate changes. Sowing maize in early spring, when the temperatures are lower, enables avoidance of drought and high summer temperatures during the flowering and grain filling stages, but it also means that maize plants will be exposed to suboptimal temperatures during earlier developmental stages. Consequently, development of maize lines tolerant to low temperatures during those stages becomes precedence. An initial study encompassed whole transcriptome sequencing of 46 maize inbred lines at V4 stage grown under optimal temperature conditions. Gene expression analysis of maize genotypes grouped as Lancaster and non-Lancaster (BSSS, Iowa dent, etc.) revealed a set of 77 differentially expressed genes (DEGs). Seven of these genes, related to abiotic stress response, were further characterized under low temperature conditions in eight inbred lines at V4 stage. Their expression showed specific profiles depending on the duration of low temperature exposure and genetic background. To test if these genes follow the same expression patterns in earlier developmental stages, the experiment was performed with 5-day old maize seedlings of two inbred lines (tolerant and sensitive), under optimal (25°/20°C) and low (8°/10°C) temperature conditions, with a 12h photoperiod. Samples for RNA extraction, cDNA synthesis and qPCR expression analysis were taken after 6h and 24h exposure to experimental temperatures. Five analyzed genes showed different expression regulation dependent on cold exposure duration. Two genes showed regulation dependent both on cold exposure duration and genetic background. Additionally, three of five DEGs showed different expression patterns at 5-day old seedling stage than at V4 stage. The results imply that processes underlying maize low temperature response are differentially regulated based on stress exposure duration, developmental stage and genetic background

Understanding low-temperature and waterlogging stress impact on early stages of maize plant development.

Abiotic stress, as an adverse environmental condition, seriously affects and limits maize productivity worldwide. Climate changes lead to altering temperatures and rainfall patterns. Earlier maize sowing enables avoiding high temperatures during silking and pollination season. As a consequence of early sowing, damages caused by temperatures lower than optimal can occur. Hence, it is very important to know the mechanism of defence against the low temperatures in the early developmental stages of the plant. Nowadays, thanks to hightroughput methods such as Next Generation Sequencing (NGS), more profound and detailed research can be conducted. A set of maize inbred lines important for commercial breeding programs at Maize Research Institute, Zemun Polje was analysed by sequencing the whole transcriptome. The aim was to identify tolerant lines for planning future hybrids, try to unravel mechanism involved in maize response to low temperatures and to identify molecular markers that could be included in breeding programs. Bioinformatic analysis of Single Nucleotide Polymorphisms (SNPs) and Diferentially Expressed Genes (DEGs) was done. Cold-induced expression analysis of several DEGs revealed different expression regulation dependent on the duration of cold stress signalizing possible important role of these genes in maize response to low temperatures. A more profound transcriptome analysis, expected to give a comprehensive insight into low-temperature induced response in early stages of plant development, is already underway. Besides low temperatures, waterlogging caused by more frequent rainfalls is another abiotic stress which can hamper the idea of early sowing, especially if combined with low-temperatures. For this reason, plant response to this stress will also be studied on the same levels as low-temperature stress, with the final goal to develop hybrids which can respond to challenging climate changes