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Author(s):  
A.S. Chernov ◽  
A.N. Minakov ◽  
E.V. Malyavina ◽  
A.S. Elfimov ◽  
G.B. Telegin

Background: Monitoring of sanitization of cage equipment is an essential function of any laboratory animal facilities, seeking to ensure the animal health and welfare. The purpose of the current study was to develop universal scale for monitoring sanitization through detection of residual ATP for the most effective process of sanitizing components of rodents micro- and macro-environment. Methods: Sterile pens and swabs for the HY-LiTE® Luminometer Instrument were used to measure ATP concentration (RLU) on the cleaned surface samples. We have examined the elements of the microenvironment (rodent and rabbit cage, cage wire meshes, feed separating pieces, water bottles with tips, houses, tunnels, IVC cage frames, cage tops and cage wire meshes). The assessed swab area on each of the surfaces was 10×10 cm. Result: We observed, that combined washing (cleaned manually and with automatic universal washers with detergent) gives the lowest RLU values. Monitoring of the quality of sanitization of equipment and surfacescan be carried out without the use of microbiological tests. Use of pre-washing allows increasing the service life of caging equipment. We have developed an assessment scale to monitor sanitizing, which can be recommended to scientific and breeding animal facilities for monitoring sanitization cage equipments.


2022 ◽  
Vol 2 ◽  
Author(s):  
William B. Brinckerhoff ◽  
Peter A. Willis ◽  
Antonio J. Ricco ◽  
Desmond A. Kaplan ◽  
Ryan M. Danell ◽  
...  

The Europan Molecular Indicators of Life Investigation (EMILI) is an instrument concept being developed for the Europa Lander mission currently under study. EMILI will meet and exceed the scientific and technical/resource requirements of the organic composition analyzer identified as a core instrument on the Lander. EMILI tightly couples two complementary analytical techniques, based on 1) liquid extraction and processing with capillary electrophoresis and 2) thermal and chemical extraction with gas chromatography, to robustly detect, structurally characterize, and quantify the broadest range of organics and other Europan chemicals over widely-varying concentrations. Dual processing and analysis paths enable EMILI to perform a thorough characterization of potential molecular biosignatures and contextual compounds in collected surface samples. Here we present a summary of the requirements, design, and development status of EMILI with projected scientific opportunities on the Europa Lander as well as on other potential life detection missions seeking potential molecular biosignatures in situ.


2022 ◽  
Author(s):  
Nahdhoit AHAMADA RACHID ◽  
Nihal Doğruöz Güngör

Abstract Some microorganisms identified in cave ecosystems have been reported to play a permanent and significant role for maintaininglife in such environments. Human entrance into caves can induce some changes on cave physic-ochemical parameters which altimately affects the living organisms. In this regard, for the first time, Morca Cave was explored to evaluate the impacts that human activities may have on the microbial diversity of the cave in a limited period of time. During this expedition at a depth of 1040 m, a camp was established for four days. Before the installation and at the end of the camp, sediments and surface samples were taken from different points of the camp area and the area around it. Sequencing of 16s rRNA of each sample was performed using the next generation sequencing method. The profile of the microbial diversity before the camping reaveled that Thermoplasmata dominated the archaea group and Gamma- and Alpha-proteobacteria were the most dominant bacterial group. After the camp, a decrease in the microbial diversity especially the previously mentioned classes strains is observed at the most of the sampled areas. The results also showed that Bacilli strains significantly increased after the camp and increase of Bacteroidia strains is observed at the most active sampled areas. This present study therefore highlights how microbial diversity inside a closed cave can respond to the human activities within a short period. Furthermore, it may constitute a solid basis to support efforts targeted at improving technics for cave management and expedition for the conservation of cave nature.


Author(s):  
Priscilla Gomes da Silva ◽  
José Gonçalves ◽  
Ariana Isabel Brito Lopes ◽  
Nury Alves Esteves ◽  
Gustavo Emanuel Enes Bamba ◽  
...  

As the third wave of the COVID-19 pandemic hit Portugal, it forced the country to reintroduce lockdown measures due to hospitals reaching their full capacities. Under these circumstances, environmental contamination by SARS-CoV-2 in different areas of one of Portugal’s major Hospitals was assessed between 21 January and 11 February 2021. Air samples (n = 44) were collected from eleven different areas of the Hospital (four COVID-19 and seven non-COVID-19 areas) using Coriolis® μ and Coriolis® Compact cyclone air sampling devices. Surface sampling was also performed (n = 17) on four areas (one COVID-19 and three non-COVID-19 areas). RNA extraction followed by a one-step RT-qPCR adapted for quantitative purposes were performed. Of the 44 air samples, two were positive for SARS-CoV-2 RNA (6575 copies/m3 and 6662.5 copies/m3, respectively). Of the 17 surface samples, three were positive for SARS-CoV-2 RNA (200.6 copies/cm2, 179.2 copies/cm2, and 201.7 copies/cm2, respectively). SARS-CoV-2 environmental contamination was found both in air and on surfaces in both COVID-19 and non-COVID-19 areas. Moreover, our results suggest that longer collection sessions are needed to detect point contaminations. This reinforces the need to remain cautious at all times, not only when in close contact with infected individuals. Hand hygiene and other standard transmission-prevention guidelines should be continuously followed to avoid nosocomial COVID-19.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261704
Author(s):  
Suzanna M. Storms ◽  
James F. Lowe

This pilot project investigated environmental SARS-CoV-2 presence in seven Midwestern meatpacking plants from May 2020 to January 2021. This study investigated social distancing and infection control practices and incorporated environmental sampling of surfaces and air in employee common areas. All plants increased their social distancing efforts, increased the frequency of cleaning and disinfecting worker areas, and screened for symptomatic people to prevent entry into the workplace. 575 samples from common areas were collected and evaluated with RT-qPCR for the presence of SARS-CoV-2. 42/367 surface samples were positive, while no virus was detected in air samples. Case positive data from the counties surrounding each plant showed peak positive SARS-CoV-2 cases from 12–55 days before the virus was detected in the plant, indicating that environmental sampling is likely a lagging indicator of community and plant infection.


Antibiotics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 38
Author(s):  
Hanane Zerrouki ◽  
Sid-Ahmed Rebiahi ◽  
Yamina Elhabiri ◽  
Ahlam Fatmi ◽  
Sophie Alexandra Baron ◽  
...  

(1) Background: The purpose of this study was to determine the prevalence of clostridia strains in a hospital environment in Algeria and to evaluate their antimicrobial susceptibility to antibiotics and biocides. (2) Methods: Five hundred surface samples were collected from surfaces in the intensive care unit and surgical wards in the University Hospital of Tlemcen, Algeria. Bacterial identification was carried out using MALDI-TOF-MS, and then the minimum inhibitory concentrations (MICs) of various antimicrobial agents were determined by the E-test method. P. sordellii toxins were searched by enzymatic and PCR assays. Seven products intended for daily disinfection in the hospitals were tested against Clostridium spp. spore collections. (3) Results: Among 100 isolates, 90 P. sordellii were identified, and all strains were devoid of lethal and hemorrhagic toxin genes. Beta-lactam, linezolid, vancomycin, tigecycline, rifampicin, and chloramphenicol all proved effective against isolated strains. Among all strains tested, the spores of P. sordellii exhibited remarkable resistance to the tested biocides compared to other Clostridium species. The (chlorine-based 0.6%, 30 min), (glutaraldehyde solution 2.5%, 30 min), and (hydrogen peroxide/peracetic acid 3%, 15 min) products achieved the required reduction in spores. (4) Conclusions: Our hospital’s current cleaning and disinfection methods need to be optimized to effectively remove spores from caregivers’ hands, equipment, and surfaces.


2021 ◽  
pp. 1-16
Author(s):  
Tom Andersen ◽  
Marlina A. Elburg

Abstract Detrital zircon in six surface samples of sandstone and contact metamorphic quartzite of the Magaliesberg and Rayton formations of the Pretoria Group (depositional age c. 2.20–2.06 Ga) show a major age fraction at 2.35–2.20 Ga, and minor early Palaeoproterozoic – Neoarchaean fractions. Trace-element concentrations vary widely, with Ti, Y and light rare earth elements (LREEs) spanning over three orders of magnitude. REE distribution patterns range from typical zircon patterns (LREE depletion, heavy REE enrichment, well-developed positive Ce and negative Eu anomalies) to patterns that are flat to concave downwards, with indistinct Ce and Eu anomalies. The change in REE pattern correlates with increases in alteration-sensitive parameters such as Ti concentration and (Dy/Sm) + (Dy/Nd), U–Pb discordance and content of common lead, and with a gradual washing-out of oscillatory zoning in cathodoluminescence images. U and Th concentrations also increase, but Th/U behaves erratically. Discordant zircon scatters along lead-loss lines to zero-age lower intercepts, suggesting that the isotopic and chemical variations are the results of disturbance long after deposition. The rocks sampled have been in a surface-near position (at least) since Late Cretaceous time, and exposed to deep weathering under intermittently hot and humid conditions. In this environment, even elements commonly considered as relatively insoluble could be mobilized locally, and taken up by radiation-damaged zircon. Such secondary alteration effects on U–Pb and trace elements can be expected in zircon in any ancient sedimentary rock that has been exposed to tropical–subtropical weathering, which needs to be considered when interpreting detrital zircon data.


2021 ◽  
Author(s):  
Aliakbar Nazari Samani ◽  
Leila Biabani ◽  
Abolhassan Fathabadi ◽  
Hassan Khosravi ◽  
Robert James Wasson ◽  
...  

Abstract Urmia Lake, the largest saline lake in Iran and the Middle East, is located in the northwest of Iran, has shrunk over the past decades. The reduced water level has increased the area of dry land around the lake allowing new environmental hazard such as sand dunes encroachment, particularly on the western side of the lake. There are five terrain types that could contribute sediment to the dunes, and it is the main aim of this research to identify the contributions to the dunes of each terrain type. Fifteen surface samples were collected from the five most erodible terrain types and eight samples were collected from the dunes both in downwind and upwind directions from the lake, and major element components were measured using X-ray fluorescence (XRF). According to the Besler classification, all samples are in the saline class. Also, the chemical index of alteration (CIA) values in all samples were less than 50, indicating weak weathering. Based on multivariate statistical analysis, suitable tracers were selected and were imported to the sourcing equations. Quantification of uncertainty and the creation of two new fingerprinting models for aeolian sediments based on both Bayesian and GLUE procedures were used. The highest proportion comes from the salty and puffy lands (44.2%) followed by salty polygon land (23.5%), clay-salty areas, puffy-flaky lands (7.01%), the terminus of the fine sandy alluvial fan (13.2%), and clay-salty abandoned lands (12.1%). It is concluded that if land managers use these results, they can more efficiently decrease the hazards posed by dune reactivation and migration though implementation of soil conservation on the affected lands around the dried lake.


2021 ◽  
Vol 9 (12) ◽  
pp. 2575
Author(s):  
Claire Bailey ◽  
Catherine Makison-Booth ◽  
Jayne Farrant ◽  
Alan Beswick ◽  
John Chewins ◽  
...  

When transferring highly infective patients to specialist hospitals, safe systems of work minimise the risk to healthcare staff. The EpiShuttle is a patient transport system that was developed to fit into an air ambulance. A validated decontamination procedure is required before the system can be adopted in the UK. Hydrogen peroxide (H2O2) vapour fumigation may offer better penetration of the inaccessible parts than the liquid disinfectant wiping that is currently suggested. To validate this, an EpiShuttle was fumigated in a sealed test chamber. Commercial bacterial spore indicators (BIs), alongside organic liquid suspensions and dried surface samples of MS2 bacteriophage (a safe virus surrogate), were placed in and around the EpiShuttle, for the purpose of evaluation. The complete kill of all of the BIs in the five test runs demonstrated the efficacy of the fumigation cycle. The log reduction of the MS2 that was dried on the coupons ranged from 2.66 to 4.50, but the log reduction of the MS2 that was in the organic liquids only ranged from 0.07 to 1.90, confirming the results of previous work. Fumigation with H2O2 alone may offer insufficient inactivation of viruses in liquid droplets, therefore a combination of fumigation and disinfectant surface wiping was proposed. Initial fumigation reducing contamination with minimal intervention allows disinfectant wipe cleaning to be completed more safely, with a second fumigation step inactivating the residual pathogens.


Author(s):  
Reymar R. Diwa ◽  
Estrellita U. Tabora ◽  
Botvinnik L. Palattao ◽  
Nils H. Haneklaus ◽  
Edmundo P. Vargas ◽  
...  

AbstractPhosphogypsum (PG) accumulates during wet-phosphoric acid production for fertilizers. In the Philippines, PG is partly (40%) utilized to produce gypsum walls and cement. This work assesses the radiological risks and resource opportunities associated with PG stacks in the Philippines. The conducted in situ radiometric survey measured the activity concentrations of 40K, 238U, and 232Th at 270 locations. Besides, another 120 surface samples were collected. Pure PG exceeds the recommended radiation limits, but simple dilution with conventional materials can make PG available as an inexpensive secondary raw material for construction. PG further contains relevant concentrations of rare earths and Y (195 ppm).


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