Influence of Printing Substrate on Quality of Line and Text Reproduction in Flexography

This study characterizes and compares the parameters of the quality reproduction of fine elements in flexography on coated and uncoated paper as well as on OPP film (oriented polypropylene). A monochrome test form was created and printed using cyan UV ink. The analysis of results confirms the importance of interaction between the printing substrate and ink; it also indicates identical line and text deformations on the print. Quality reproduction on coated paper is higher in relation to OPP film for all the research parameters. The ink penetrates significantly more and with more irregularity into the pores and throats of the uncoated paper, which results in less homogeneous elements, and in such way that it loses its original shape. In coated paper and OPP film, the ink spreads more on the substrate area which gives it a significantly more homogeneous shape. However, due to the surface spread of the ink, the biggest changes in the size of fine elements are noticeable in the OPP film. The scientific contribution of this paper is based on the comparison of print quality parameters of fine elements, which can contribute to the optimization of the production process and quality of the final graphical product.

Response of Controlled Cell Load Biofilms to Cold Atmospheric Plasma Jet: Evidence of Extracellular Matrix Contribution

Aim: Study of the biocidal effect of a cold atmospheric-pressure plasma in ambient air on single-species bacterial biofilms with controlled cell density, characterized by different extracellular matrices. Methods and results: Two bacterial strains were chosen to present different Gram properties and contrasted extracellular matrices: Pseudomonas aeruginosa ATCC 15442 (Gram-negative), and Leuconostoc citreum NRRL B-1299 (Gram-positive). P. aeruginosa biofilm exhibits a complex matrix, rich in proteins while L. citreum presents the specificity to produce glucan-type exopolysaccharides when grown in the presence of sucrose. Plasma was applied on both surface-spread cells and 24-h grown biofilms with controlled cell loads over 5, 10, or 20 min. Surface-spread bacteria showed a time dependent response, with a maximal bacterial reduction of 2.5 log after 20 min of treatment. On the other hand, in our experimental conditions, no bactericidal effect could be observed when treating biofilms of P. aeruginosa and glucan-rich L. citreum. Conclusions: For biofilms presenting equivalent cell loads, the response to plasma treatment seemed to depend on the properties of the extracellular matrix characterized by infrared spectroscopy, scanning electron microscopy, or dry weight. Significance and impact of study: Both cell load standardization and biofilm characterization are paramount factors to consider the biocide effect of plasma treatments. The extracellular matrix could affect the plasma efficacy by physical and/or chemical protective effects.

Overview of Spray Aerosols for Disinfection Against Airborne and Surface Spread of Covid-19

The global outbreak of SARS-Cov-2 (called Covid-19) has claimed many lives, with currently over 59.95 million confirmed cases of infected persons and over 1.4 million deaths worldwide. Spray aerosols used to disinfect areas, surfaces, and objects are crucial to preventing and protecting people against Covid-19. This paper presents and examines various available and approved materials to formulate spray aerosols for disinfection against Covid-19. The formulations are discussed based on the active ingredient and the possible contact time. The virus can be inactivated. The major groups of spray aerosols discussed include quaternary ammonium-based sprays, hydrogen peroxide-based sprays, alcohol-based sprays, acid-based sprays, sodium-based sprays, and other formulations, some of which are recommended by the US Environmental Protection Agency. Information presented here could benefit governments, policymakers, communities, researchers, health workers, and the general public during this pandemic and beyond.

Novel coronavirus disease 2019 (COVID-19) and challenges in dental practices

The Covid-19 virus appearing in Wuhan in December, 2019 and acting by binding to ACE-2 receptors in the respiratory system has caused many people to die by spreading to the whole world. The virus, which has been detected to spread faster than SARS-CoV and MERS-CoV viruses, spreads from person to person rapidly. People should not be together because it is transmitted from person to person through the respiratory tract. For this reason, it is recommended not to go to health institutions, provided that it is not urgent. However, many emergency patients go to dental clinics and hospitals for treatment. In this review; with possible contamination routes of Covid-19 such as airborne spread, contact spread and contaminated surface spread during patient diagnosis and treatment to prevent Covid-19 contamination, methods preventing spread such as hand hygiene, personal protective measures for dentists, intraoral rubber dam before dental procedures were indicated. It was also mentioned that the fast rotating tool with valves having negative pressure should be used and most importantly, the materials used in the dental clinic should be disposed in accordance with medical waste protocol. How to cite this article: Novel coronavirus disease 2019 (COVID-19) and challenges in dental practices. Int Dent Res 2020;10(3):100-15. https://doi.org/10.5577/intdentres.2020.vol10.n3.5 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Mycological and chemical screening of maize at open Nigeria

The aim of the present study was to screen maize at the open markets in Osun state, Nigeria to determine species of fungi total aflatoxin content and changes inproximate, energy and some vitamins content of maize grains. A total of forty five mouldy maize samples were collected from the six different open markets within the region which were later bulked into six representative samples (20-50Kg) for each market while Aflasafe maize, obtained from the Internationa lInstitute of Tropical Agriculture (IITA) was used as a control.There presentative samples from the bulk were taken for proximate,selected vitamins and total aflatoxin contents determination.The quantitative enumeration of fungias colony forming units per gram of the grains (CFU/g) was performed using the surface spread method in different culture media. The results of fungi profile were further expressed as fungal isolation frequency (IF) and relative density (RD). Twelve (12) species and seven fungi genera were isolated in this study. The total fungi count ranged from 1.50x10 to 2.1X10 CFU/g in the six different locations. Aspergillus flavus, Rhyzopus stolonifer and Aspergillus glaucus were the most prevalent species Aspergillus and Rhizopus species occurred at 100% and 87% (IF) respectively. The toxigenic species of Aspergillus, Fusarium and Penicellium had 85.7%,14.3% and 14.3% RD respectively. The proximate contents of the mouldy maize reduced by 11.54% for crude protein, 12.72% for ether extract and 1.12% for ash while about 5% caloric loss was observed. Total Aflatoxin in mouldy maize rose from near zero in aflasafe maize to 267.41µg/Kg with an average value of 142.0µg/Kg in mouldy maize while retinol and tocopherol contents were depleted by 48.7% and 37.6% respectively. This study indicated substantial loss of nutrients and reduced feed value in maize due to mould contamination and the need for continuous assessment offered ingredients particularly maize for mycological and nutritive status in order to feed animals for optimal performance

Mycotoxicolgical evaluation of indigenous varieties of wheat from Quetta, Balochistan, Pakistan.

The present study was designed to investigate the mycological contamination and aflatoxigenic potential of fungi isolated from the indigenous certified varieties of wheat. Surface spread method was used to determine mycological contamination whereas to determine the toxigenic potential of isolated fungi and screening of wheat grains for aflatoxin contamination thin layer chromatography was used. All the collected samples revealed fungal contamination however none of the fungal isolate showed aflatoxigenic potential. Similarly all the samples showed negativity for aflatoxin. It can be concluded that for human public health, cereal grains must be subjected to quality control and mycotoxicologicalexaminations.

The effect of wind- soil- structure interaction on the longitudinal response of high-rise buildings

In this work, the modelling of the wind impact on the standard tall building of CAARC (Commonwealth Advisory Aeronautical Council), which is placed on a surface spread footing, is done numerically utilizing the ABAQUS program. The wind is demonstrated as an exponential way in the boundary layer of the atmosphere. Then, stream turbulence is modeled by the ILES technique and a cosimulation is accepted to exchange non-uniform loads from fluid to structural nodes. Damping of the structure is controlled by the Rayleigh strategy. Mechanical reaction of the footing-soil framework is modeled utilizing direct strategy. Infinite boundary conditions have been added to the numerical model for the simulation of free boundaries, and reasonable contact elements for sliding and separating between subsurface components are considered. Finally, fluid solutions and structural reactions are compared with the mean and root mean squares of experimental estimations on an extensive range of reduced speeds. Numerical results for the framework of soil-structure systems were compared with base conditions without association of soil-structure interaction. It is concluded that dynamic properties and reactions of the building influence soil-structure interaction and accordingly the planners should consider these parameters keeping in mind to guarantee the practical designing.

Polymicrobial multidrug-resistant bacteria isolated from street vended fresh fruit juices in Pakistan

Purpose The purpose of this paper is to evaluate the prevalence and antibiograms of bacteria isolated from various fresh fruit juices at a local market in Faisalabad. Design/methodology/approach Fresh fruit juice samples (n=125) were randomly collected using aseptic technique. Each sample (10 mL) was serially diluted with 90 mL of sterile peptone water, from 1×10−1 to 1×10−5. Each dilution was then used to inoculate nutrient agar by surface spread plating. Aerobic colony counts (ACCs) were determined by colony counting. The isolates were sub-cultured on blood and MacConkey agar. Preliminary identification was achieved on the basis of colony morphology and culture characteristic, and confirmed by API® 20E, 20NE, and API® Staph testing. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer disk diffusion assay, per CLSI 2015 guidelines. Findings The mean ACC ranged from 2.0×106 CFU/mL to 4.93×106 CFU/mL, with the highest ACC determined for orange juice. Overall, 153 polymicrobial were identified in 125 samples; 103 of these were Gram-negative rods (GNR) and 28 were Gram-positive cocci (GPC). Escherichia coli (n=38), Klebsiella pneumoniae (n=32) and Pseudomonas aeruginosa (n=24) were the predominant GNR; Staphylococcus aureus (n=28) was the predominant GPC. Antibiogram analysis revealed that all GNR were resistant to ampicillin. However, most E. coli isolates were resistant to ceftazidime (72.4 percent of isolates), and ceftriaxone and cefepime (68.9 percent), while most K. pneumoniae isolates were resistant to cefepime (72 percent) and ceftriaxone (64 percent). All S. aureus isolates were resistant to penicillin, while most (64 percent) were resistant to piperacillin; the most effective drugs against bacteria were vancomycin and imipenem. Practical implications The findings suggest that the local government regulatory food and public health authorities should take immediate emergency measures. Appropriate surveillance studies and periodic monitoring of food items should be regularly performed to safeguard public health. Originality/value The current study revealed the prevalence of multidrug-resistant bacteria in freshly prepared fruit juices sold by local street vendors.

Modelling Oil Spill around Bay of Samsun, Turkey, with the Use of Oilmap and Adios Software Systems

Bay of Samsun is one of the most important oil transport gateways in Black Sea. The region is surrounded with the coasts which have various levels of environmental sensitivity. The purpose of this study is to investigate the oil spill and predict the future accidents likely to be encountered around the Bay of Samsun. To be well informed about fate, this study makes the best possible use of two trajectory models. One of them, ADIOS (Automated Data Inquiry for Oil Spills), has been applied to natural degradation calculations, and the other one, OILMAP (oil spill model and response system), has been used for surface spread simulation. Hence in order to identify the risky areas three scenarios have been developed. Their results reveal that in case of oil spills, with average environmental conditions, there is a risk of contamination for the city of Samsun. Although the area under the risk is the same, contamination density is totally different depending upon the quantity and the type of spilt oil. The results gained through these efforts are hoped to be useful for many organizations dealing with oil spill response operations and contribute to an effective coordination among the relevant institutions.