Work Surfaces Research Articles

Avaliação de Riscos no Setor da Tatuagem: podem utilizar-se os Métodos MARAT, William Fine e MIAR?

Introduction / background / objectives The Tattoo sector is still little addressed in the context of Occupational Health. There are many documents about Risk for tattooed clients, but the information is scarce in relation to the Tattooist. The bibliography found in this sense is not exhaustive, it just gives a general idea of ​​some Labor Risks, with no quantitative assessment, much less hierarchical. Methodology After conducting a Review related to Risk Assessment methods and after the elaboration of a Risk Letter from a Tattoo studio, three methods were selected: MARAT (Methodology for Assessment of Risks and Accidents at Work) , William Fine (WF) and MIAR (Integrated Method for Risk Assessment), due to the ease of access to information on how to use them, suitability for the sector and facility; these were applied to 68 risk factors included in the highlighted work tasks. Content The main tasks considered in the Tattoo workstations observed were: making the drawing on paper or on the skin; or select the design to put on the skin, from the computer; insert the design on decal sheets; shave the skin; disinfect/ sterilize the skin; transfer the design of the decal sheet to the skin; prepare the workbench with the necessary utensils and products; paint the skin using the tattoo machine; wipe off uninjected and excess ink from the skin; placing various chemicals on the skin during the tattoo (variable among professionals); help the client in case of lipothymia or syncope (if necessary); as well as cleaning/ disinfecting/ sterilizing surfaces and work instruments. Conclusions Although the three methods value different aspects, it was very interesting to verify the homogeneity of the results, that is, the MARAT technique marked eight items as belonging to the category of highest risk; the WF methodology and MIAR highlighted seven and nine, respectively. Among the three methods, there were six risk factors that were included in the highest risk category, namely the eventual contact with chemical agents, sharp objects and blood potentially contaminated with relevant microorganisms during the act of inserting pigment in the skin, as well as during the cleaning of the skin (of the excess pigment, between injections). Only the MIAR method indicated two items that the other techniques did not include in this category (namely the eventual contact with blood during the cleaning/ disinfection/ sterilization of work surfaces and work instruments), which the MARAT and William Fine technicians both placed in the second and third category, respectively. The method that most valued the worker’s risk factors in general was MIAR (nine items in the highest risk category and thirty-seven in the lowest risk category), the opposite being William Fine (seven items in the risk category) highest and forty-six in the lowest risk).

Evaluation of Sanitation as a Preventive Measure of Foodborne Diseases in the Bakery Operation

Every step from production through consumption can influence the microbiology of food products. Unsanitary equipment and insufficient hygienic level in the food industry lead to increased populations of microorganisms and can compromise quality and safety. Proper use of disinfectants can complement an effective sanitation program. Sanitation is an important part of the HACCP system, as its application significantly eliminates microorganisms in the production process. The system is an auxiliary control body for monitoring compliance with hygiene procedures. As a result of non-compliance with sanitation procedures, food products are contaminated and undesirable foodborne illnesses of the consumer occur. The epidemiology of foodborne diseases is rapidly changing as newly recognized pathogens emerge and well recognized pathogens increase in prevalence or become associated with new food vehicles. In this work, we focused on cleaning and disinfection of surfaces that significantly affect the hygienic safety of the resulting products. The purpose of sampling was to assess the effectiveness of disinfection in a bakery in order to prevent the occurrence of foodborne diseases. For disinfection, a 3% concentration of Savo disinfectant was used. Surface hygiene control was performed using microbiological swabs before the start of production, during production and after disinfection. Samples were taken from work surfaces floor, wall, table, tray and mixer. Disinfectant Savo was effective on floor, wall, tray and mixer where were detected the significant decrease of colony forming units of total count of bacteria, coliform bacteria and moulds after disinfection. On these monitored surfaces no bacteria after disinfection was detected. On the table were detected 3colony forming units of total count of bacteria after disinfection which represent decrease of microorganisms, in compare with numbers of microorganisms before production. The results from the microbiological swabs show that disinfectant Savo was able to decrease the number of colonies forming units after disinfection.

Котки різних конструкцій. Інженерний аналіз

Comparative field tests of similar in design ring-spur and gear-spur rollers for soil rolling provide their developers and users with information on the understanding of the design and technological features. The Goal of research – engineering analysis of structures of ring-spur and gear-spur rollers according to the criteria of weight, shape of working surfaces, soil pressure, completeness of compaction, penetrating ability in the range of depth of pre-sowing and surface tillage. Methods and Materials. Engineering analysis involved the study of three types of rollers. The research hypothesis assumed that the combination of weight characteristics of rollers and their geometric shapes of working surfaces in contact with the soil, in statics will provide the inherent properties of each cat (the first stage of research), which will potentially focus on choosing the most acceptable criteria for comparing functional features of rollers. necessary for field research in dynamics (the second stage of research). According to the criteria of static research were selected: penetrating ability (1); soil pressure (2); completeness of compaction of the area (3); direction of clamping forces (4); features of working surfaces (5); the nature of the mounting of solid disks on the shaft (6). Methodologically, the first three criteria required special adaptations (capacities) with the ability to change the height of the soil layer in the range of depths of pre-sowing and sowing tillage. Other criteria were supposed to be carried out by organoleptic evaluation. The study was supposed to be carried out on soil characteristic of the Forest-Steppe zone and homogeneous in fractional composition, to exclude the influence of soil inclusions of different sizes. Evaluation of soil characteristics was performed by thermostatic-weight method, according to the generally accepted method of "cutting ring" [Kaczynski, 1947] with a cylinder volume of 100 cm3. To determine the area of one elementary working surface of the annular disk, the application of a marking grid on its imprint on the surface left in the soil layers hmin, hmid, hmax was used. When determining the pressure on the soil, depending on the height of the treated layer, the marking grid was superimposed on the imprint of several areas of elementary working surfaces, which were fixed on the chord of immersion in the soil of the annular segment. Statistical analysis of experimental data was performed by the method of analysis of variance according to [Dospekhov, 1985] and interpreted by standard computer programs Excel and graphs. Results. According to the physical characteristics (weight and geometric parameters) of the roller combines the proximity of the diameter of the disks, the width of the working surfaces on the edge of the generator, the presence of spurs. The difference lies in the dimensional characteristics that fall on the width of the grip, the presence of aggressive protruding shapes (teeth) in the gear-spur structure. Each roller has an individual layout of elementary work surfaces. This allowed the conditional marking of rollers as "classic", "modernized" and "specialized". The working surfaces of the classic and specialized rollers provide vertical and lateral action of the clamping forces, while the modernized forms them in the vertical direction. These forces for each of the rollers are derived from the orientation of the working surfaces of different configurations (flat narrow, flat wide; a combination of point-focused with trapezoidal). In addition, work surfaces can have a one- or two-level sequence of contact with the soil at a variable depth. It is established that the nature of the attachment of adjacent disks on the shaft can be rigid or movable. Definitions of concepts and their estimation on indicators of pressure, completeness of consolidation, penetrating ability are resulted. Conclusions. According to the indicators of engineering analysis, each of the three rollers is predicted to have its inherent dominant feature for the most effective use in milling, pre-sowing and post-sowing tillage operations. It is determined that the most acceptable criteria for further research in the dynamics of variable speed should be the intensity of crushing lumps, the degree of soil compaction, the intensity of soil compaction, sticking of the working surface of the roller in high humidity, self-cleaning ability. The criteria of further research in dynamics are determined.

Pragmatic protocols for working cleanly when measuring ice nucleating particles

Measuring ice nucleating particles (INPs) is critical for understanding, and modeling, cloud formation, reflectivity, and precipitation patterns. However, because INPs are very rare in the atmosphere, but abundant—sometimes alarmingly so—in the dust that covers all work surfaces, contamination during processing of collected aerosol samples can be a significant hindrance to obtaining accurate measures of INPs. In preparing this technical note, we questioned the cleanliness of every collection and processing step involved in making immersion freezing measurements of INPs re-suspended from filter samples. The aim was to identify, and then minimize, all potential sources of significant contamination, including containers and tools used to store filters and prepare liquid suspensions, gloves, work surfaces, and the polymerase chain reaction (PCR) trays commonly used for sample analysis. While plasticware released few INPs, most gloves readily shed them, but this can be mitigated by using washed cleanroom vinyl or polyethylene gloves. Work surfaces, even those that had been cleaned, were prodigious reservoirs of contaminating INPs, but simply covering them with aluminum foil will provide an INP-free surface. By applying these practices, we developed a method to reduce the background level of INPs on Nuclepore™ polycarbonate filters in our tests to 0 at −25 °C and < 20 at −27 °C, making them suitable for use in all sampling environments.

Determination of the structural efficiency of quadric and cylindrical surfaces when used as reinforced concrete roof structures

Modern architecture of civil engineering structures made of reinforced concrete is demanding solutions to problems related to design and construction of roofs shaped as creative forms which require an adequate combination of arts and physical-mathematical models. In that sense, the quadric and cylindrical surfaces offer an attractive based on their volumetric expression, historicity, and mathematical feasibility. In this work, seven cylindrical and quadric surfaces named elliptic cylinder, parabolic cylinder, elliptic cone, elliptic paraboloid, hyperbolic paraboloid, ellipsoid and hyperboloid of two sheets have been analysed to find out which of them show to be more efficient when used as reinforced concrete roof structures. To do so, the configuration of each structure hase been adjusted in terms of similar stiffness, strength parameters and enclosed volume. The structural efficiency was computed using the results of weight/load ratio, available strength, material consumption and relative stiffness. The solution of the model has been achieved using a combination of exact solutions and numerical methods. To compute the model results a Matlab® code was written and validated using the structural software SAP2000®. The best structural efficiency in terms of stiffness, strength, and materials consumption was obtained for roofs configurated using surfaces built from parabolas, i.e., elliptic paraboloid, hyperbolic paraboloid, and parabolic cylinder. The results of this work can be used in future studies and applications related to arhitectural comfort, structural behaviour and material consumption in construction of roofs.

Selection of modes for laser cladding of PR-08Kh17N8S6G powder

A brief analysis of powders used in the industry for surfacing on the work surfaces of critical parts is given in order to increase their wear resistance. The results of experimental studies on the choice of parameters of gas-powder cladding modes are presented. The cladding process was carried out by a laser robotic complex with a coaxial feed of powder to the surfacing zone. The substrate used steel grade 08H18N10T, which was applied to the melt of wear-resistant powder grade PR-08H17N8S6G. The use of ytterbium fiber laser allowed to reduce the heat supply to the surfaces, which significantly reduced the residual stresses in the workpiece. Variable parameters of the laser cladding process were the output power of laser radiation, processing speed, and powder mass flow rate. During visual inspection, the absence of pores and cracks were used as the estimated indicators of the cladding. The study of macro geometry single clad track was conducted on cross section of the clad. During measurements, the quality of a single clad track was determined by its geometric dimensions: clad height, clad width, contact angle between the tangent to the cladding surface and the substrate plane, as well the depth of the mixing layer of the surfaced and substrate materials. According to the results of experimental studies of the selected optimal mode, providing a cladding track with a clad height above 1 mm; clad width 2.5 mm; the depth of the mixing layer – 0.2 mm; contact angle between the tangent to the clad surface and the substrate more than 50º. This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation. Agreement on the provision of subsidies No. 075-15-2019-1833 dated December 03, 2019. Unique identifier PNI RFMEFI60419Kh0245.

Sargassum contamination and consequences for downstream uses: a review

Sargassum spp. are brown algae present in the tropical and subtropical waters of the world’s oceans. Benthic or pelagic, Sargassum spp. represent substantial amounts of biomass when drifted and massive beaching events also named “golden tides” are challenging for environmental and tourism managers. The Sargassum spp. biomass can be regarded as offering economic opportunities; however, micropollutant contamination counteracts this wealth. This review describes the contaminant uptake processes and the concentrations reached by various Sargassum species in regard to national and international norms for a variety of applications. Amongst the heavy metals, perhaps total arsenic content is the most salient: phytoaccumulation of arsenic is due to confusion in the phosphate transporter between arsenic and phosphate, thus leading Sargassum spp. to bioaccumulate arsenic actively. The levels reached could well give cause for concern across all potential applications, in particular for human and animal use. Similarly, there are concerns for the widespread applications or disposal of this biomass due to environmental impacts in the case of storage, landfill or composting. Organic micropollutants are too rarely studied to assert that there is global contamination. However, research studies focused on Sargassum spp. contamination confirmed environmental threats. But, without exhaustive analysis of routine algae contamination, the standard contamination level cannot be defined. Treating beach-cast or drifting Sargassum spp. as a waste is a Gordian knot, in that it involves investment, work and disposal surfaces, whilst not necessarily providing environmental and economic gains. However, Sargassum spp. are a raw material, a resource rich in a broad variety of constituents that could be processed for commercial applications or which could be used for production of energy. In this paper the authors review the diverse applications that can be considered and describe the relevant regulations and norms related to contaminants and effluents that need to be taken into account. However, if valorizing Sargassum spp. is currently valuable and promising, the quality of the raw material is a key starting point because fresh and sand-free algae are required: offshore gathering solutions need to be developed in order to limit Sargassum sp. contamination by pollutants from land so as to hinder algae decay.

Content analysis of food safety implications in online flour-handling recipes

PurposeNumerous food recalls and outbreaks were associated with wheat flour in recent years. Few consumers are cognizant of food safety risks associated with raw flour. The purpose of this study is to evaluate the food safety information and flour-handling behaviors presented in popular food blog recipes and in YouTube videos using cookie, cookie dough and egg noodle recipes as examples.Design/methodology/approachEighty-five blog recipes and 146 videos were evaluated. Blog author and video host food-handling experience was classified as professional or nonprofessional. Food safety information and food-handling behaviors were evaluated for adherence to government and scientific recommendations.FindingsBlog authors and video hosts demonstrated higher awareness of food safety risks associated with raw eggs compared to raw flour, which only translated into better adherence with recommended food-handling behaviors during ingredient addition steps. Cross-contamination from adding raw flour to the product was observed in 25% of videos, whereas cross-contamination from hosts adding raw shell eggs was observed 3% of videos. Blog authors and video hosts did not recommend or demonstrate handwashing after handling raw shell eggs nor raw flour, and fewer than 5% provided recommendations for cleaning work surfaces. Heat treatment methods to convert raw flour into ready-to-eat products were mentioned by 24% of blog authors and 18% of video hosts; however, the recommendations were not scientifically validated.Originality/valueThis study demonstrates the need to develop educational interventions that increase blog authors' and video hosts' awareness of risks associated with raw flour and that translate this knowledge into practiced behaviors.

Characterization of Surface Topographies Generated using Circular- and Cylindrical-Face EDT

Large area texturing using EDT is challenging due to surface damage resulted from inefficient discharges, such as arcs and short-circuits. Also, three-dimensional analyses of surface topography generated during electrical discharge texturing (EDT) are scarcely performed in the available literature. Therefore, in this work, two modes of EDT were developed for large area texturing based on the mode of electrode movement resulting in texture generation on work surfaces: circular-face EDT (CirEDT) and cylindrical-face EDT (CylEDT), and the generated surface topographies are characterized in terms of topography images, areal texture parameters, and scanning electron microscopy images. Parametric analyses are also performed to study the influences of the operating parameters, such as discharge current, pulse on-time, and peripheral velocity, on different areal texture parameters. Topography analyses reveal that these surfaces have a characteristic stochastic distribution of microstructures in shape, size, and location. Height parameter analyses reveal that CylEDT surfaces are twice positively skewed and have a higher kurtosis as compared to the CirEDT surfaces. Spatial parameter analyses reveal that both surfaces display dominance of isotropic nature and non-directional structures. CirEDT surfaces have higher lubricant retention capacity, but lesser wear volume available for running-in period as compared to CylEDT surfaces, as per volume parameter analyses. Discharge current and pulse on-time are identified as the significant parameters influencing the majority of the areal texture parameters analyzed. SEM analysis revealed that CylEDT results in a textured surface with sea-wave-like structures, whereas CirEDT results in a textured surface with lunar-craters-like structures.

Повышение долговечности переводников бурильных колонн электромеханической обработкой

Increasing the durability of drill pipe subs is a pressing problem, a solution to which will improve the efficiency of oil and gas companies when drilling wells. Outer diameter wear, tears on the end surfaces of couplings and the end surfaces of pins, as well as blemishes on external and internal conical rotary-shouldered connections are the most typical defects of the subs. A study and comparative bench tests of the 5135 steel subs with the Z-117 screw were conducted. Testing of the subs with hardening of the work surface by electromechanical processing was done in comparison with the base technology (hardening and high tempering) and carbonitriding. The drill pipe subs were manufactured and hardened by OOO Alexandrovsky Drilling Equipment Plant on the 1М63 machine modernized for electromechanical processing. The comparative bench tests of the drill pipe subs were conducted by OOO Kovrovsky Drilling Equipment Plant on the coupling makeup machine MC-4 by screwing on / unscrewing threaded connections, taking into account the Russian Federation standards and recommendations of the American Petroleum Institute API 7. Electromechanical processing, being one of the method of hardening by a concentrated flow of electric energy of industrial frequency, builds up a gradient layer with the hardness of 52–56 HRC on the surface of the drill pipe subs. The results of the screwing on / unscrewing tests of threaded connections with a toot-joint thread demonstrated high efficiency of carbonitriding and electromechanical processing (500 and more cycles) as a method of increasing hardness of the work surfaces and low efficiency of the current bulk heat treatment (up to 47–66 cycles).

Management of bacteriological specimens of patients suffering from coronavirus disease 2019 (COVID-19)

Management of bacteriological specimens of patients suffering from coronavirus disease 2019 (COVID-19)

Parametric studies on finishing of inconel 718 flat surfaces with chemically assisted magnetic abrasive finishing process

With progressions in technological advancements, many materials that can withstand adverse conditions in their working environment are in high demand. Inconel 718 is one of few such materials which is widely used for various industrial applications such as nuclear industries, marine applications, solar power stations, heat exchanger tubing etc. But due to its superior attributes, Inconel 718 is quite hard to finish with traditional machining/finishing processes. A hybrid finishing process: Chemically assisted magnetic abrasive finishing method can be employed to finish the flat surface of Inconel 718. Three major process factors: Processing time, Chemical concentration and weight percentage of abrasives have been selected. Experiments have been designed using Response Surface Methodology (RSM). Effect of these three selected process parameters on Percentage Improvement in Surface Finish (PISF) has been analyzed with ANOVA. Scanning Electron Microscopy (SEM) is also utilized to observe the effects of process factors on surface microstructure. Results indicate that Chemically assisted Magnetic abrasive finishing can be successfully implemented to finish flat Inconel 718 work surfaces and parameters like Processing time, Chemical concentration and Weight percentage of abrasives have significant effect on PISF.

Room for Improvement: Results of a Baseline Evaluation of Environmental Cleaning in a Resource-Limited Neonatal Unit

Background: Contamination of the near-patient hospital environment including work surfaces and equipment, contributes to skin colonization and subsequent invasive bacterial infections in hospitalized neonates. In resource-limited settings, cleaning of the neonatal ward environment and equipment is seldom standardized and infrequently audited. Methods: A baseline multimodal assessment of surface and equipment cleaning was performed in a 30-bed high-care neonatal ward in Cape Town, South Africa, October 7–9, 2019. Adequacy of routine cleaning was evaluated using ATP bioluminescence assays, fluorescent ultraviolet (UV) markers, and quantitative bacterial surface cultures. For flat surfaces (eg, tables, incubators, trolleys), a 10×10-cm template was used to standardize the swab inoculum; for small equipment and devices with complex surfaces (eg, humidifiers, suction apparatus, stethoscopes), a standard swabbing protocol was developed for each item. Swabs in liquid transport medium were processed in the laboratory by vortexing for 30 seconds, plating onto blood and MacConkey agars, and incubating at 37°C for 48 hours. Manual counting of bacterial colony forming units was performed, followed by conventional biochemical testing and/or VITEK automated identification. Results: Of 100 swabs (58 from surfaces and 42 from equipment), 11 yielded growth of known neonatal pathogens (Enterobacteriaceae, A. baumannii, P. aeruginosa, S. aureus, S. agalactiae, and enterococci), 36 isolated potential neonatal pathogens (mostly coagulase-negative staphylococci). In addition, 4 grew environmental organisms and 49 showed no growth. The highest aerobic colony counts (ACCs) were obtained from swabs of suction tubing, milk kitchen surfaces, humidifiers, and sinks; the median ACC from swabs with any bacterial growth (n = 51) was 3 (IQR, 1–22). Only 40% of the 100 surface and equipment swabs had ATP values &lt;200 relative light units (RLU) threshold for cleanliness. Median ATP values were 301 (IQ range, 179–732) RLUs for surface swabs versus 230 (IQ range, 78–699) RLUs for equipment swabs (P = .233). Of the 100 fluorescent UV markers placed on near-patient surfaces and high-touch equipment, only 23% had been removed after 2 staff shift changes (24 hours later). Surfaces had a higher proportion of UV marker removal than equipment (19 of 58 [32.8%] vs 4 of 42 [9.5%]; P = .008). Conclusions: Environmental cleaning of this neonatal ward was suboptimal, especially for equipment. Improvement of environmental cleaning practices is an important intervention for neonatal infection prevention in resource-limited settings. Future studies should evaluate the impact of staff training, environmental cleaning tools and repeated audit with feedback, on the adequacy of cleaning in neonatal wards.Funding: Funding: for the laboratory work was provided by The Society for Healthcare Epidemiology of America (SHEA) International Ambassador Alumni Research Award and a South African Medical Research Council Self-initiated Research (SIR) Grant to Angela Dramowski, who is supported by a NIH Fogarty Emerging Global Leader Award K43 TW010682.Disclosures: None

Handling and processing of pathology samples of suspected or confirmed COVID-19 patient

The SARS-CoV-2 has emerged as a major public health concern. Human to human transmission has been confirmed via droplets, contaminated surfaces, and hands. All the staffs and personnel working in the laboratory are also at risk of contracting this infection, especially during the handling and processing of samples from suspected or confirmed patients of COVID-19. With no definite treatment and vaccine in sight, the way forward is to break the chain of transmission by eliminating the risk of exposure to laboratory staffs by proper handling and processing of all the samples in an appropriate containment level laboratory, proper use of personal protective equipment with special attention on disposal and decontamination of work surfaces.

Tailoring Wetting Properties at Extremes States to Obtain Antifogging Functionality

AbstractFog formation decreases light transmission of optically clear materials. A promising approach to address this problem is to control the wetting properties of the material at extremes states, which requires imparting micro and nano morphology features on the surface. However, such features may affect the optical properties of the surface. In this work, superhydrophobic and superhydrophilic surfaces, with different morphology characteristics ranging from nanoscale to hierarchical micro‐nanoscale are fabricated and evaluated in order to investigate which wetting extreme and surface morphology is more suitable to preserve the light‐transmitting properties and exhibit antifogging functionalities. The performance of the aforementioned surfaces is compared for the first time in two different testing modes: under intense fog flow and no surface cooling, and under no‐flow and surface cooling, which enhances dew condensation on the surfaces. It is demonstrated that superhydrophilic surfaces with nanoscale morphology maintain their optical transmittance under fog flow for more than 20 min. This duration is one of the longest reported in the literature revealing the long‐term antifogging functionality of the proposed surfaces. Finally, by tailoring the morphology and the surface wetting properties, an optically switching surface (initially “milky” which becomes “clear”) when exposed to humidity is demonstrated.

Application of HACCP system in catering system and microbiological quality of roasted chicken meals

This study aimed to work out the microbiological quality of roasted chicken ready to eat meals (n=240), swabs of labor surfaces (n=390), and the food handlers hands (n=90) in catering services within the university dormitory females to assure a secure supply of food for colleges students.The results obtained appeared no contamination with L. monocytogenes, Salmonella spp., Shigella spp., and Clostridium perfringens before the applying of the HACCP framework. While the fluctuation within the microbial numerous total viable bacteria, total molds and yeasts, B. cereus, Staph. aureus, spore-formers, and coliforms in served meals ascribed to inadequate handling or processing procedures, multiplication of microorganisms during thawing and cutting of chicken, poor hygiene of utensils, and equipment as well as the survival of microorganisms to the cooking process.The examined chicken samples from receiving to serving were 1.12×105, 7.4 X 103, 2.8 X 104, and 1.6 X 103 in washing chicken, thawing, and washing steps respectively. The lowest value was 3.98×103, 3.2 X 102, 1.2 x 103, and 6.1 X 102 in serving, dressing, washing, and receiving steps, respectively. Swabs samples analysis which taken before and after HACCP application from handlers, utensils, equipment and work surfaces observed different levels of significance in the reduction of microbial load in one or more of selected examination. Application of the HACCP framework shows a low rate of examined microorganism with a decreasing percentage reached 100% of 1 or more microbial groups in serving step and p < 0.05 which demonstrates a critical impact of HACCP application. HACCP framework can be moreover utilize to control the safety and quality of prepared ready to eat meals, based on specializing laboratory to do the necessary microbial analysis, whether by the ministry of Health, Universities or by the specifications to reduces the reliance on the end product inspection that ultimately resulted in improving food safety, reducing costs associated with food hazards.

Comprehensive Analyses of SARS-CoV-2 Transmission in a Public Health Virology Laboratory.

SARS-CoV-2 has become a major global concern as of December 2019, particularly affecting healthcare workers. As person-to-person transmission is airborne, crowded closed spaces have high potential for rapid virus spread, especially early in the pandemic when social distancing and mask wearing were not mandatory. This retrospective study thoroughly investigates a small-scale SARS-CoV-2 outbreak in Israel’s central virology laboratory (ICVL) in mid-March 2020, in which six staff members and two related family members were infected. Suspicions regarding infection by contaminated surfaces in ICVL facilities were nullified by SARS-CoV-2 negative real time polymerase chain reaction (PCR) of work surfaces swipe tests. Complete SARS-CoV-2 genomes were sequenced and mutation analyses showed inclusion of all samples to clades 20B and 20C, possessing the spike mutation D614G. Phylogenetic analysis clarified transmission events, confirming S1 as having infected at least three other staff members and refuting the association of a staff member’s infected spouse with the ICVL transmission cluster. Finally, serology tests exhibited IgG and IgA antibodies in all infected individuals and revealed the occurrence of asymptomatic infections in additional staff members. This study demonstrates the advantages of molecular epidemiology in elucidating transmission events and exemplifies the importance of good laboratory practice, distancing and mask wearing in preventing SARS-CoV-2 spread, specifically in healthcare facilities.

Skin Exposure to Acrylates in Nail Salons.

The nail salon industry has seen significant growth in recent years. Nail technicians provide manicures, pedicures and apply artificial nails; tasks that expose them to chemicals, including acrylates that are known skin and respiratory sensitizers. This paper reports on potential skin exposure to acrylates among nail technicians in Toronto, Canada. Hand skin wipes were collected after (i) the application of artificial nails, (ii) the application of ultraviolet cured gel nail polish, and (iii) deliberate contact with nail polish. Surface wipes were collected from work areas and surfaces contaminated with known products. Wipe samples were analysed for eight acrylates: methyl acrylate (MA), ethyl acrylate (EA), methyl methacrylate (MMA), ethyl methacrylate (EMA), 2-hydroxyethyl acrylate (HEA), 2-hydroxyethyl methacrylate (HEMA), 2-hydroxypropyl methacrylate (HPMA), and ethylene glycol dimethacrylate (EGDMA) by gas chromatography with mass spectrometry. Thirty-five wipe samples were collected. No acrylates were detected in skin samples (n = 8) or work surfaces (n = 6). However, MMA, EMA, EA, HEMA, and HPMA were detected in the samples of surfaces contaminated with known products. MMA was detected in 28% of products tested. HEMA and HPMA were detected where deliberate contact with nail polish occurred. These results confirm that acrylates are present in nail products. However, no acrylates were detected in skin wipes. MMA, a chemical prohibited for use in cosmetics in Canada, was detected in nail polishes. Nail technicians should continue to employ safe work practices that reduce the probability of skin contact with acrylates and other chemicals.

The use of ozone-air mixture for the disinfection of milk catheters

Intracisternal drug treatment of bovine mastitis involves the use of sterile instruments, eliminating re-infection or infection from animal to animal. The use of the ozone-air mixture showed the possibility of effective use for disinfection of milk catheters, work surfaces and instruments made of various materials. The experiments were carried out on metal, wood and plastic test materials and milk catheters. The optimal exposure time for the disinfection of milk catheters and test material made of metal was 30 minutes, of wood - 60 minutes, and of plastic - 70 minutes.

The Sizing of Plate-Fin Exchangers to Fixed Dimensions Within a Volume Design Region

This paper shows the development of a design approach for plate and fin heat exchangers to meet fixed dimensions. This approach adopts the concept of volume design region that establishes the limits within which the physical dimensions (length, width and height) of a specific design problem can be set. The design region is determined by minimum and maximum dimensions. The heat exchanger volume is dictated by the problem specifications and the type of secondary surface used on each of the fluids. High density surfaces tend to produce small volumes, while the opposite applies to low density surfaces. In principle, if the heat transfer and friction factor correlations for secondary surfaces are expressed as a function of the geometrical parameters that define the fin density, then it possible to fix the surface density boundaries that give the smallest and largest exchanger volume. The design methodology presented in this work enables to include exchanger dimensions as a design objective along with the heat load and the pressure drop. To achieve these objectives, surface design is a central strategy. In this work, triangular, louvered, rectangular and offset surfaces are used to demonstrate the methodology.