Spatial distribution and identification of elements and oxides in surface sediments of the Boka Kotor bay

Ovo istraživanje sprovedeno je u Bokokotorskom zalivu radi procene kvaliteta površinskog sedimenata, a time i stanja morske sredine. ED-XRF metodom elementarne analize određen je sadržaj velikog broja elemenata i oksida u površinskim sedimentima uzorkovanih sa 12 lokacija u 2019. godini. Multivarijantnom statističkom analizom, kao što su analiza glavnih komponenati (PCA) i klaster analiza (CA), urađena je analiza dobijenih podataka kako bi se dobila sveobuhvatna raspodela ispitivanih elemenata po lokacijama u zalivu i njihovo poreklo, kao i sličnosti/razlike grupa uzoraka u hemijskom sastavu.This study was carried out in the Bay of Boka Kotor in order to assess the surface sediment quality and thereby to evaluate the status of the marine environment. The method of elementary analysis, ED-XRF was used to determine the content of elements and oxides in surface sediments sampled at 12 stations in 2019. Multivariate statistical methods, such as principal component analysis (PCA) and cluster analysis (CA) were used to analyse the data in order to obtain a comprehensive distribution of the examined elements according to locations in the bay, and their origin, as well as similarities/differences of samples in chemical composition.49. godišnja konferencije o aktuelnim problemima korišćenja i zaštite voda „Voda 2020“, Trebinje, 19. – 20. novembar 2020

Persistence and Turnover in Desert Plant Communities during a 37-yr Period of Land Use and Climate Change

Understanding long‐term changes in ecological communities during global change is a priority for 21st‐century ecology. Deserts, already at climatic extremes, are of unique interest because they are projected to be ecosystems most responsive to global change. Within a 500‐km2 landscape in the Mojave Desert, USA, we measured perennial plant communities at 100 sites three times (1979, 2008, and 2016) during 37 yr to evaluate six hypotheses of community change. These hypotheses encompassed shifts in community measures (e.g., diversity, cover) and species elevational distributions, biotic homogenization, disproportionately large change at the highest elevations, relationships between turnover and species’ responses to disturbance and drought, and that environmental refugia (e.g., moist topographic positions) would receive species during climatic warming and drying. Most community measures changed temporally, such as species density (species/600 m2) increasing 23% and plant cover doubling between 1979 and 2016. There was no increase in nonnative species and minimal evidence for biotic homogenization. High‐elevation communities did not display greater change than low‐elevation communities. ... See full text for complete abstrac

Aptamers for pharmaceuticals and their application in environmental analytics

Aptamers are single-stranded DNA or RNA oligonucleotides, which are able to bind with high affinity and specificity to their target. This property is used for a multitude of applications, for instance as molecular recognition elements in biosensors and other assays. Biosensor application of aptamers offers the possibility for fast and easy detection of environmental relevant substances. Pharmaceutical residues, deriving from human or animal medical treatment, are found in surface, ground, and drinking water. At least the whole range of frequently administered drugs can be detected in noticeable concentrations. Biosensors and assays based on aptamers as specific recognition elements are very convenient for this application because aptamer development is possible for toxic targets. Commonly used biological receptors for biosensors like enzymes or antibodies are mostly unavailable for the detection of pharmaceuticals. This review describes the research activities of aptamer and sensor developments for pharmaceutical detection, with focus on environmental applications

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Durability and Fire Resistance of Laterite Rock Concrete

Abstract The ability of a structure to retain its structural integrity in adverse conditions of weather and fire out break depends on its durability and fire resistance. This research work investigated these indispensable properties in Laterite Rock Concrete to assess its usability structural concrete. Durability was investigated in terms of water absorption, density, shrinkage and fire resistance. Fire resistance test was carried out using direct fire test. Two mix proportions: 1:2:4 and 1:1½:3 were tested at optimum water/cement ratio of 0.6 and 0.55 for 1:2:4 and 1:1½:3 mixes respectively. From the results, it is concluded that the concrete is durable, environmentally compatible and possesses high fire resistance properties, having satisfied the relevant codes requirements. The 1:2:4 and 1:1½:3 conform to the specifications for grades 15 and 20 correspondingly. Recommendations include specifications for designing structural elements using the Laterite Rock Concrete. Keyword

Case Study: Using Soil Survey to Help Predict Sonoran Desert Tortoise Population Distribution and Densities

Soils properties can affect the ability of an animal to dig burrows for habitat and survival purposes. The Sonoran (Gopherus morafkai) and Mojave Desert Tortoise (Gopherus agassizii) require burrows that are at least 20 inches deep to help them thermoregulate during the cold of winter and heat of summer. Soils that have characteristics that restrict their “digability” would be expected to limit the population density and distribution of animals such as the Sonoran or the Mojave Desert Tortoise regardless of the amount of forage vegetation being produced. The Sonoran Desert Tortoise in Mohave County, Arizona, and possibly throughout its range may seek “habitats of opportunity” within boulder piles, under exposed bedrock, and in caliche caves due to the limited “digability” of the soils endemic to this part of the Sonoran Desert. The natural availability of thermoregulating burrowing habitat and temperature/precipitation records should be considered when interpreting any fluctuations in Sonoran Desert Tortoise population densities. © 2017 The Society for Range ManagementThe Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information