The role of Permeable Double Skin Façades on the onset of VIV on high-rise buildings

The application of stand-alone permeable screens for the mitigation of vortex shedding problems is a wellknown option in wind engineering, usually adopted for bridges. Nevertheless, their employment in buildings is still in its early stages. Porous coverings are employed for aesthetic reasons and, recently, also for their capability to reduce the energetic impact of the building. Within this framework, the Permeable Double Screen Fa & ccedil;ades (PDSFs) are becoming popular in the architectural trends, but their effects on the building's aerodynamics are still an open topic. Specifically, it is still unclear which could be the role of the permeable layer on the vortex shedding mechanism, which currently represents one of the main design issues for tall and super tall buildings. The present study proposes an experimental investigation of the role of the PDSF in the vortex-induced vibrations (VIVs) of a prismatic building model with an aspect ratio B/D = 3.33. A semi-aeroelastic model of the building is tested for different Scruton numbers and a comparison between the PDSF and the solid fa & ccedil;ade case is proposed. Results highlight that the effectiveness of the PDSF in structural response mitigation appears to be dependent on the Scruton number and a threshold over which the PDSF successfully mitigates the onset of VIV is found

Nanostructured Bismuth Electrodes for Non-Enzymatic Paracetamol Sensing: Development, Testing, and Computational Approach

In this work, new Screen Printed Carbon-paste Electrodes (SPCEs) were developed through deposition of nanostructures of HO–BiONO3 synthesized with or without surfactant additions. We performed a cyclic voltammetry study showing the improvement in performance of bismuth tailored electrodes for paracetamol sensing compared with bare SPCE. A computation study was also performed for investigating the interaction between paracetamol and bismuth species during the electron transfer process enlighten the preferential sites of interaction on the surface of modified SPEs

A Review on Recent Advancements of Graphene and Graphene-Related Materials in Biological Applications

Graphene is the most outstanding material among the new nanostructured carbonaceous species discovered and produced. Graphene’s astonishing properties (i.e., electronic conductivity, mechanical robustness, large surface area) have led to a deep change in the material science field. In this review, after a brief overview of the main characteristics of graphene and related materials, we present an extensive overview of the most recent achievements in biological uses of graphene and related materials

Chemical Composition of Aspergillus creber Extract and Evaluation of its Antimicrobial and Antioxidant Activities

Among the species belonging to the Aspergillus section Versicolores, Aspergillus creber has been poorly studied and still unexplored for its biological activities. The present study was undertaken to analyze A. creber extract and to evaluate its in vitro antimicrobial and antioxidant activities. UHPLC-MS/MS analysis of A. creber extract allowed the characterization of five known fungal metabolites including: asperlactone, emodin, sterigmatocystin, deoxybrevianamide E, and norsolorinic acid. The highest antimicrobial activity was displayed against Candida albicans, with a mean strongest inhibition zone of 20.6 ± 0.8 mm, followed by Gram-positive drug-resistant bacteria. The MIC values of A. creber extract varied from 0.325 mg/ml to 5 mg/ml. A. creber extract was shown a potent antioxidant activity and a high level of phenolic compounds by recording 89.28% scavenging effect for DPPH free radical, 92.93% in ABTS assay, and 85.76 mg gallic acid equivalents/g extract in Folin-Ciocalteu assay. To our knowledge, this is the first study concerning biological and chemical activities of A. creber species. Based on the obtained results, A. creber could be a promising source of natural antimicrobial and antioxidant compounds

Antibacterial Properties of Bacterial Endophytes Isolated from the Medicinal Plant Origanum heracleoticum L

Background: Bacterial endophytic communities associated with medicinal plants synthesize a plethora of bioactive compounds with biological activities. Their easy isolation and growth procedures make bacterial endophytes an untapped source of novel drugs, which might help to face the problem of antimicrobial resistance. This study investigates the antagonistic potential of endophytic bacteria isolated from different compartments of the medicinal plant O. heracleoticum against human opportunistic pathogens. Methods: A panel of endophytes was employed in cross-streaking tests against multidrug-resistant human pathogens, followed by high-resolution chemical profiling using headspace-gas chromatography/mass spectrometry. Results: Endophytic bacteria exhibited the ability to antagonize the growth of opportunistic pathogens belonging to the Burkholderia cepacia complex (Bcc). The different inhibition patterns observed were related to their taxonomic attribution at the genus level; most active strains belong to the Gram-positive genera Bacillus, Arthrobacter, and Pseudarthrobacter. Bcc strains of clinical origin were more sensitive than environmental strains. Cross-streaking tests against other 36 human multidrug-resistant pathogens revealed the highest antimicrobial activity towards the Coagulase-negative staphylococci and Klebsiella pneumoniae strains. Interestingly, strains of human origin were the most inhibited, in both groups. Concerning the production of volatile organic compounds (VOCs), the strain Arthrobacter sp. OHL24 was the best producer of such compounds, while two Priestia strains were good ketones producers and so could be considered for further biotechnological applications. Conclusions: Overall, this study highlights the diverse antagonistic activities of O. heracleoticum-associated endophytes against both Bcc and multidrug-resistant (MDR) human pathogens. These findings hold important implications for investigating bacterial endophytes of medicinal plants as new sources of antimicrobial compounds

Antibacterial activity of Arthrobacter strains isolated from Great Gobi A Strictly Protected Area, Mongolia

Desert soil hosts many microorganisms, whose activities are essential from an ecological viewpoint. Moreover, they are of great anthropic interest. The knowledge of extreme environments microbiomes may be beneficial for agriculture, technology, and human health. In this study, 11 Arthrobacter strains from topsoil samples collected from the Great Gobi A Strictly Protected Area in the Gobi Desert, were characterized by a combination of different techniques. The phylogenetic analysis, performed using their 16S rDNA sequences and the most similar Arthrobacter sequences found in databases, revealed that most of them were close to A. crystallopoietes, while others joined a sister group to the clade formed by A. humicola, A. pascens, and A. oryzae. The resistance of each strain to different antibiotics, heavy -metals, and NaCl was also tested as well as the inhibitory potential against human pathogens (i.e., Burkholderia ssp., Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus ssp.) via cross -streaking, to check the production of metabolites with antimicrobial activity. Data obtained revealed that all strains were resistant to heavy metals and were able to strongly interfere with the growth of many of the human pathogens tested. The volatile organic compounds (VOCs) profile of the 11 Arthrobacter strains was also analyzed. A total of 16 different metabolites were found, some of which were already known for having an inhibitory action against different Grampositive and Gram-negative bacteria. Isolate MS -3A13, producing the highest quantity of VOCs, is the most efficient against Burkholderia cepacia complex (Bcc), K. pneumoniae, and coagulase-negative Staphylococci (CoNS) strains. This work highlights the importance of understanding microbial populations' phenotypical characteristics and dynamics in extreme environments to uncover the antimicrobial potential of new species and strains

Predicting needlestick and sharps injuries in nursing students: Development of the SNNIP scale

© 2020 The Authors. Nursing Open published by John Wiley & Sons Ltd. Aim: To develop an instrument to investigate knowledge and predictive factors of needlestick and sharps injuries (NSIs) in nursing students during clinical placements. Design: Instrument development and cross-sectional study for psychometric testing. Methods: A self-administered instrument including demographic data, injury epidemiology and predictive factors of NSIs was developed between October 2018–January 2019. Content validity was assessed by a panel of experts. The instrument's factor structure and discriminant validity were explored using principal components analysis. The STROBE guidelines were followed. Results: Evidence of content validity was found (S-CVI 0.75; I-CVI 0.50–1.00). A three-factor structure was shown by exploratory factor analysis. Of the 238 participants, 39% had been injured at least once, of which 67.3% in the second year. Higher perceptions of “personal exposure” (4.06, SD 3.78) were reported by third-year students. Higher scores for “perceived benefits” of preventive behaviours (13.6, SD 1.46) were reported by second-year students