This paper investigates the durability of cement-bound layers with steel slag as a partial aggregate replacement. Mixtures with various amounts of slag and cement are investigated for their ...durability after freeze-thaw cycles and exposure to de-icing agent. Optical microscopy analysis is conducted as a method for assessing the behaviour of low-strength material in order to determine why the application of slag resulted in greater compressive strength and durability properties. It was shown that this method is suitable for providing more details and insights into the material's internal structure. All the mixtures show a loss in compressive strength after exposure to freeze-thaw cycles and de-icers, but this loss is more pronounced in mixtures with gravel-only aggregates. A strong linear correlation is obtained between 28-day compressive strength and retained compressive strength after 10 freeze-thaw cycles. The main conclusion of the research presented here is that steel slag aggregate presents good potential for use in adverse climates, and it is possible to predict the freeze-thaw resistance of cement-bound aggregate on the basis of compressive strength.
Purpose: The main purpose of this paper is to develop a further understanding of professional accountants’ attributes and professional skills required by employers. This paper analyses the ...requirements of the labour market of the Republic of Croatia using the framework derived from IFAC’s International Education Standard (IES) 3 from 2015 to identify the specific dimensions of professional skills in job advertisements.
Methodology: This study uses a qualitative data collection method to analyse the required professional skills of professional accountants from the accounting employers’ perception. We have used Internet research to collect primary data and analyse job advertisements. Content analysis was used to analyse job advertisements.
Results: The evidence suggests that employers mostly required professional accountants with attributes categorised as the organisational skills dimension. They were followed by attributes categorised as the intellectual skills dimension, the interpersonal and communication dimension, and the personal dimension. Taking into account the professional skills dimension, a professional accountant is required to possess the ability to use appropriate information technology (IT), teamwork skills, responsibility, the ability to work independently, be analytical and committed to learning, since those were most highly ranked attributes in the collected job advertisements.
Conclusion: This study revealed a ‘profile’ of a professional accountant considering the requirements of employers regarding professional skills. Future research should take into consideration further analysis regarding the required skills using different data sources and explore the required skills within different accounting related professions and various sectors and sizes of accounting employers.
Vancomycin-resistant Enterococcus faecium (VREfm) is an opportunistic pathogen among the highest global priorities regarding public and environmental health. Following One Health approach, we ...determined for the first time the antibiotic resistance and virulence genes, and sequence types (STs) affiliation of VREfm recovered simultaneously from marine beach waters, submarine outfall of a wastewater treatment plant and an offshore discharge of untreated sewage, and compared them with the surveillance VREfm from regional university hospital in Croatia to assess the hazard of their transmission and routes of introduction into the natural environment. Importantly, VREfm recovered from wastewater, coastal bathing waters and hospital shared similar virulence, multidrug resistance, and ST profiles, posing a major public health threat. All isolates carried the vanA gene, while one clinical isolate also possessed the vanC2/C3 gene. The hospital strains largely carried the aminoglycoside-resistance genes aac(6′)-Ie-aph(2″)-Ia, and aph(2″)-Ib and aph(2″)-Id, which were also predominant in the environmental isolates. The hyl gene was the most prevalent virulence gene. The isolates belonged to 10 STs of the clonal complex CC17, a major epidemic lineage associated with hospital infections and outbreaks, with ST117 and ST889 common to waterborne and hospital isolates, pointing to their sewage-driven dissemination.
To gain better insight into the diversity of accompanying taxons in the surveyed water matrices, microbiome taxonomic profiling was carried out using Illumina-based 16S rDNA sequencing and their resistome features predicted using the PICRUSt2 bioinformatics tool. An additional 60 pathogenic bacterial genera were identified, among which Arcobacter, Acinetobacter, Escherichia-Shigella, Bacteroides and Pseudomonas were the most abundant and associated with a plethora of antibiotic resistance genes and modules, providing further evidence of the hazardous effects of wastewater discharges, including the treated ones, on the natural aquatic environment that should be adequately addressed from a sanitary and technological perspective.
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•Hospital and environmental vancomycin-resistant Enterococcus faecium were studied.•VREfm enter marine environment by outfalls of treated and untreated wastewater.•VanA genotype predominates among hospital and waterborne isolates in Croatia.•Hospital and environmental VREfm carry similar virulence and resistance genes.•Microbiome analysis revealed accompanying pathogenic taxa and resistance genes.
Acinetobacter baumannii zauzima posebno mjesto unutar skupine uzročnika teških infekcija, poznatije kao “ESKAPE” mikroorganizmi. Ovaj mikroorganizam postao je vodeći uzročnik hospitalnih infekcija u ...21. stoljeću, te su brojna istraživanja usmjerena na epidemiologiju, rezistenciju i nadzor nad ovim patogenom. Epidemiologija i molekularna osnova rezistencije kliničkih izolata Acinetobacter baumannii u Hrvatskoj tijekom posljednja dva desetljeća bitno se promijenila u većini zdravstvenih ustanova, uz visoki postotak rezistencije na karbapeneme, kinolone i aminoglikozide, te prisutnost multiplo-rezistentnih izolata. U ovom pregledu naglasak je stavljen na rezultate istraživanja epidemiologije i rezistencije kliničkih izolata iz Hrvatske.
•Beneficial effects of slag/cement on compressive strength and elastic modulus.•Inconvenient guidelines for characterization of cement stabilized material-CSM.•3D digital image correlation method is ...appropriate for CSM characterization.•Strong correlation between compressive strength and CSM modulus of elasticity.•Possible prediction of elastic properties of CSM using presented equations.
Accurate design of pavement behavior requires elastic properties of all the constituting layers. Measuring of elastic modulus on crude surfaces, by contact based mechanical devices, often results in a high dispersion of determined values. Therefore, application of multiple measurement methods on six different mixtures is presented, among which an innovative approach using spatial digital image correlation. Obtained results indicate that there is a strong correlation between the compressive strength and the dynamic and static modulus. Thus, by using presented equations it is possible to predict elastic properties of cement bound aggregate by measuring just one of the relevant parameters.
Antimicrobial peptides (AMPs) are promising candidates for new antibiotic classes but often display an unacceptably high toxicity towards human cells. A naturally produced C-terminal fragment of ...PGLa, named PGLa-H, has been reported to have a very low haemolytic activity while maintaining a moderate antibacterial activity. A sequential tandem repeat of this fragment, diPGLa-H, was designed, as well as an analogue with a Val to Gly substitution at a key position. These peptides showed markedly improved in vitro bacteriostatic and bactericidal activity against both reference strains and multidrug resistant clinical isolates of Gram-negative and Gram-positive pathogens, with generally low toxicity for human cells as assessed by haemolysis, cell viability, and DNA damage assays. The glycine substitution analogue, kiadin, had a slightly better antibacterial activity and reduced haemolytic activity, which may correlate with an increased flexibility of its helical structure, as deduced using molecular dynamics simulations. These peptides may serve as useful lead compounds for developing anti-infective agents against resistant Gram-negative and Gram-positive species.
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•PGLa-H is one of the smallest natural antimicrobial peptides but is poorly active.•Doubling its size in a tandem repeat enhanced peptide activity.•A rationally guided point mutation (Val15→Gly) improved peptide selectivity.•Cytotoxicity and genotoxicity towards host blood cells were low for both peptides.•Peptides were bactericidal for multidrug resistant clinical isolates.
Rejuvenation in z ∼ 0.8 Quiescent Galaxies in LEGA-C Chauke, Priscilla; van der Wel, Arjen; Pacifici, Camilla ...
Astrophysical journal/The Astrophysical journal,
05/2019, Letnik:
877, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We use reconstructed star formation (SF) histories of quiescent galaxies at z = 0.6-1 in the Large Early Galaxy Astrophysics Census survey to identify secondary SF episodes that, after an initial ...period of quiescence, moved the galaxies back to the star-forming main sequence (blue cloud). 16 3% of the z ∼ 0.8 quiescent population has experienced such rejuvenation events in the redshift range of 0.7 < z < 1.5 after reaching quiescence at some earlier time. On average, these galaxies first became quiescent at z = 1.2, and those that rejuvenated, remained quiescent for ∼1 Gyr before their secondary SF episode, which lasted ∼0.7 Gyr. The stellar mass attributed to rejuvenation is on average 10% of the galaxy stellar mass, with rare instances of an increase of more than a factor of 2. Overall, rejuvenation events only contribute ∼2% of the total stellar mass in z ∼ 0.8 quiescent galaxies and we conclude that rejuvenation is not an important evolutionary channel when considering the growth of the red sequence. However, our results complicate the interpretation of galaxy demographics in color space: the galaxies with rejuvenation events tend to lie in the so-called "green valley," yet their progenitors were quiescent at z ∼ 2.
The long-standing goal in the field of peptide antibiotics has been to design lead compounds that have a wide spectrum of excellent antibacterial activity but are nontoxic to human cells. ...Gram-negative and Gram-positive bacteria have very different membranes, which are additionally modified in some drug-resistant species, presenting a challenge for the design of a single membrane-active peptide able to adapt its conformation to various physical properties of membrane microenvironments. In this paper, we describe how a peptide sequence can be constructed starting from an adaptable dynamic turn tandem motif in a central location. The peptide, named flexampin, has been examined firstly by molecular dynamics simulations. It uses a flexible central motif and designed helix-forming cationic amphipathic arms to form a boomerang-like, L-shape, V-shape, and hairpin, super-secondary structures, whichever is the best in matching amphipathic and hydrophobic microenvironments it encounters. Secondly, activity measurements showed that flexampin is bactericidal at low micromolar concentrations against Gram-positive and Gram-negative strains including some multidrug resistant clinical isolates, while it is nontoxic for human circulating blood cells, does not cause DNA damage, and has good selectivity for bacterial cells in comparison to human cells. It is the first membrane-active peptide designed with the ability to self-adjust the orientation of its two cationic helical arms, 3D-hydrophobic moment, and dipole moment for obtaining a better grasp of anionic polar head groups at bacterial membrane surfaces.
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•In silico designed peptide can adjust its structure to membrane surface charge.•Flexible central hinge enables increased activity against bacterial strains.•Orientation & magnitude of dipole moment favor entrance into anionic membrane.•Molecular dynamics simulations connect structural changes to selectivity.
The aim of this study was to determine the susceptibility of hospital and environmental Acinetobacter baumannii isolate biofilms on ceramics and glass to common disinfectants benzalkonium chloride ...and chlorhexidine. For this purpose we developed a new method for biofilm cultivation and quantification on ceramics. The biofilm bacteria were more resistant to disinfectants than the planktonic populations, as more than 50 % of the biofilm population and none of the planktonic population survived 5-minute exposure. Furthermore, biofilm populations on ceramic tiles were significantly more resistant than those on glass coverslips, even though the amount of biofilm was practically the same on ceramics and glass. The reason for reduced susceptibility of A. baumannii biofilms on ceramics may be related to surface/disinfection interactions. Our findings suggest that biofilms on ceramic surfaces can be an important source of A. baumannii infection in hospital environments.
Intenzivna primjena informacijskih tehnologija u svakodnevnom poslovanju ne mijenja samo tradicionalne načine obavljanja računovodstvenih zadataka, već traži i specijalizirana znanja i vještine. U ...tom smislu, od iznimnog je značaja edukacija vezana uz informacijske tehnologije i primjenu informacijskih tehnologija u računovodstvu, a koju budući profesionalni računovođe stječu tijekom formalnog obrazovanja na visokoškolskim institucijama. Cilj rada je istražiti pojavnost kolegija koji pružaju edukaciju o informacijskim tehnologijama na računovodstvenim smjerovima, na preddiplomskoj i diplomskoj razini studija, na visokoškolskim institucijama s AACSB akreditacijom (eng. The Association to Advance Collegiate Schools of Business) u odabranim europskim zemljama. U radu se također identificiraju vrste informacijskih tehnologija koje se izučavaju u okviru kolegija na računovodstvenim smjerovima na preddiplomskoj i diplomskoj razini studija. U istraživanju je korištena metoda analize sadržaja web stranica, pri čemu je analiziran 51 studijski program računovodstvenog usmjerenja. Rezultati provedenog empirijskog istraživanja nadopunjuju postojeće spoznaje pružajući uvid u informacijske tehnologije koje se izučavaju na preddiplomskoj i diplomskoj razini studijskih programa računovodstvenog usmjerenja u europskom kontekstu, a koje u značajnoj mjeri korespondiraju tehnologijama koje se primjenjuju u recentnoj računovodstvenoj praksi.
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