Cleaning Protocol Research Articles

Performance assessment of solar PV panels under varying environmental conditions: a laboratory and field-based approach for sustainable energy in mining operations.

This study provides a novel and comprehensive assessment of solar photovoltaic (PV) panel performance under varying environmental conditions, integrating laboratory experiments with real-world field studies to address challenges specific to mining operations. The research uniquely explores the combined effects of shading, temperature, humidity, dust deposition, and tilt angle, delivering actionable insights for optimizing PV systems in harsh conditions. Laboratory experiments demonstrated that a parallel configuration significantly minimizes power losses under partial shading, while a rise in temperature from 35 to 75°C resulted in a notable 21.34% and 29.12% power output reduction for monocrystalline and polycrystalline panels, respectively. Furthermore, increased humidity (65.40 to 98.20%) caused a 35.82% decline in power output due to scattering effects. Field studies conducted in a surface mining environment revealed that dust accumulation led to a substantial 43.18% drop in maximum power output after 5days, emphasizing the importance of regular cleaning. Optimal energy capture was achieved at a 15° tilt angle, aligning with the site's latitude. These findings underscore the novelty of using combined experimental approaches and field validation to improve PV performance in mining operations. Practical recommendations, including parallel configurations to mitigate shading losses, temperature regulation strategies, and frequent cleaning protocols, are proposed to enhance the sustainability and efficiency of renewable energy systems in challenging environments.

P-359. Healthcare Practitioners' Infection Prevention Strategies and Associated Factors in Primary Healthcare Facilities of Rohingya Refugee Camps in Bangladesh: A Qualitative Study

Abstract Background Healthcare-associated infections (HAIs) pose significant challenges to both patients and healthcare providers. Rohingya refugee camps in Bangladesh are the most densely populated in the world. In the primary healthcare facilities of Rohingya refugee camps, healthcare-associated infections pose major barriers to safe and high-quality healthcare delivery among Rohingya refugees. The study's goal was to evaluate infection prevention strategies and associated factors among primary healthcare practitioners in Rohingya refugee camps. Methods In 2023, we conducted a qualitative study among primary healthcare practitioners identified from 15 primary healthcare facilities in 15 Rohingya refugee camps. We conducted 60 in-depth interviews and six focus group discussions with community healthcare providers. We reviewed the collected data, developed a coding system, analyzed the data, and summarized findings according to the study objectives and themes. Results Respondents were 60 % men and 40 % women, with a median age of 30 years, and 85% had higher secondary education. All respondents were employed for a median of 3 months (range,1-36 months). Only 42.5% of primary healthcare practitioners were knowledgeable about infection prevention strategies, and 37.2% practiced good infection prevention. Primary healthcare providers who had higher education and formal training in IPC were significantly more likely to have good infection prevention practices. Effective infection prevention practices were linked to the availability and accessibility of hand washing facilities and soap, proper use of personal protective equipment, appropriate cleaning and disinfection protocols, adherence to infection prevention guidelines, surveillance of healthcare-associated infections, and adequate knowledge of infection prevention measures of primary healthcare providers. Conclusion Effective infection prevention and control practices are crucial for minimizing the risk of HAIs. This study assessed the infection prevention knowledge and practices, and their associated factors among primary healthcare practitioners in Rohingya refugee camps which would help develop and implement effective interventions to reduce HAIs within Rohingya refugee camps. Disclosures All Authors: No reported disclosures

P-356. Reduction of high-touch surface aerobic bacteria and fungi colony counts with the implementation of ActivePure continuous disinfection technology

Abstract Background As hospitals nationwide rebound from the effects of the COVID pandemic, reduced staffing and increased hospital-acquired infections (HAIs) are still challenges. Surface disinfection plays a pivotal role in the prevention of HAIs. To improve high-touch surface disinfection and remove the dependence on the human factor, ActivePure continuous disinfection technology devices were installed in the Medical Intensive Care Unit (MICU) HVAC system at Ochsner LSU Health Shreveport in October 2023. ActivePure is a novel technique that kills microbes in the environment by using an advanced photocatalytic oxidation particle. Methods A prospective study was conducted in the 19-bed MICU. Two weeks before device activation, 50 high-touch surface samples and 10 reservoir samples were collected by sterile sponge in situ and plated onto Nutritive (tryptic soy) agar for total aerobic microbial counts, Selective (Sabouraud dextrose) agar for total fungal counts, selective (MeReSa) agar for total MRSA counts, and CHROMagar selective for Carbapenem-Resistant Acinetobacter baumannii (CRAB). All agar plates were incubated at 30°C or 37°C (as applicable) for 48-96 hours. For evaluation, serial dilution plate counts were used to calculate the CFU per sponge for each media type. The detection limit was 10 CFU/sponge for each evaluation. After 4 weeks post-activation, 50 high-touch surface samples and 10 reservoir samples from the same pre-activation sample locations were collected and evaluated via the same methods, and the same was repeated at 9 weeks post-activation. Routine cleaning and disinfection protocols were unchanged during the entire study period. Figure 2 Results The mean aerobic bacterial and fungi surface CFUs were reduced over 99.78% (Fig 1). The mean MRSA surface CFUs were reduced by 99.99% and the mean CRAB surface CFUs were reduced by 99.75% (Fig 2). There was a 94% reduction in surfaces with greater than 500 CFUs/100cm2 of MRSA. There was a 100% reduction in reservoirs with greater than 500 CFUs/100cm2 of CRAB and 80% reduction in reservoirs with greater than 10 CFUs/100cm2 of CRAB. Conclusion The ActivePure continuous disinfection technology devices significantly reduced total aerobic bacteria, including MRSA, difficult-to-treat CRAB, and fungi surface colony counts on high-touch surfaces. Disclosures Kimberly Trosch, RN, BSN, ActivePure Technologies: Full time employee Daniel Marsh, n/a, ActivePure Medical: Advisor/Consultant

Is differential cleaning needed for SARS-CoV-2 beyond standard procedures? A systematic review

Background: There is a substantial risk of indirect transmission of SARS-CoV-2 from contaminated surfaces and objects in healthcare settings.Aim: To evaluate the effectiveness of enhanced cleaning protocols for high-touch surfaces during COVID-19, focusing on cleaning products, concentrations, contact time, and recommended frequency.Setting: We focused on research conducted in healthcare settings or where samples were obtained from healthcare environments.Method: We assessed studies that compared different cleaning, disinfection, sterilisation, or decontamination procedures and cleaning frequency with standard or routine procedures. We prioritised randomised trials, non-randomised controlled trials, controlled before-and-after studies, and interrupted time series analyses carried out between 01 January 2020 and 31 August 2022.Results: Three studies met our criteria from 2139 references searched. These studies, which took place in Iran, China and the United States, found that routine terminal cleaning and enhanced terminal cleaning with different cleaning enhancements significantly reduced SARS-CoV-2 surface contamination. One of the studies tested residual SARS-CoV-2 levels after routine and terminal cleaning with varying strengths of disinfectant and evaluated the efficacy of two common types of disinfectants in inactivating SARS-CoV-2 on inanimate surfaces in different hospital wards.Conclusion: Limited evidence supports cleaning strategies that can reduce the transmission of SARS-CoV-2 from surfaces in healthcare settings. Combining various cleaning methods and using multiple disinfectants can effectively reduce surface contamination.Contribution: Randomised controlled trials are crucial for evaluating cleaning effectiveness. They must outline cleaning protocols, detailing frequency, product concentration and volume, application methods, soil and surface types, and environmental conditions, to provide strong evidence.

Changeover method for biosafety cabinets using ozone gas.

This study evaluated the effectiveness of a biosafety cabinet equipped with an ozone generator, particularly during the transition periods between the production of cell products. As living cell products cannot undergo sterilization, maintaining an aseptic manufacturing environment is paramount. Raw materials, often derived from human tissues, are frequently contaminated with various resident bacteria, necessitating environmental resets after each process. The utility of this device against bacteria, including endotoxins, endospores, and fungi endemic to human tissues, could facilitate safe and reproducible production changeovers through a simplified, one-button operation. This study focused on bacteria resistant to conventional cleaning protocols, specifically targeting endospore-forming bacteria with robust resistance to disinfectants, spore-forming fungi, and included analyses of endotoxins. The effects of ozone exposure on Pseudomonas aeruginosa (an endotoxin-producing bacterium), Bacillus subtilis (an endospore-forming bacterium), and Aspergillus brasiliensis (a spore-forming fungus) were assessed. In the dedicated biosafety cabinet equipped with an ozone generator, the treatment group exposed to ozone showed a significant reduction in both colony-forming units and endotoxin levels in Pseudomonas aeruginosa at 1.0 × 104 colony-forming units (CFUs) compared to the control group. Moreover, the ozone treatment markedly decreased the colony formation of Bacillus subtilis endospores and Aspergillus brasiliensis spores. Given its effectiveness against endospores and endotoxins-among the most challenging bacterial derivatives to eliminate-the device demonstrates potential for enhanced bacterial control in Grade A biosafety cabinets within cell product manufacturing facilities. The system may substantially reduce operator stress by ensuring product safety through straightforward operational procedures and high reproducibility, although further validation is required.

Magnetic and Biomedical Properties of Iron Nanoparticles Synthesized Using Vitex agnus-castus Extract.

Magnetic nanoparticles have attracted significant attention in nanoscience and nanotechnology due to their unique physicochemical properties. These properties enable their great potential in various biomedical applications, such as hyperthermia, drug delivery, tissue engineering, theranostics, and lab-on-a-chip technologies. Physical and chemical methods are conventionally used for the synthesis of nanoparticles; however, due to several limitations of these methods, research focus has recently shifted towards developing clean and eco-friendly synthesis protocols while maintaining their desirable chemical and physical properties. In this study, iron oxide nanoparticles (FeNPs) were synthesized for the first time using the green synthesis method with extracts from Vitex agnus-castus. The structural and magnetic characterization of FeNPs was carried out using state-of-the-art techniques. The formation of FeNPs was confirmed by UV-vis spectroscopy. The morphology and size distribution were examined by a zetasizer and SEM, which showed agglomerated ring-shaped structures with a moderate size distribution among the nanoparticles. The crystalline structure and phase purity of the FeNPs were analyzed by XRD. FT-IR spectroscopy confirmed the attachment of bioactive plant molecules on the FeNP surfaces. The TGA results indicated the presence of organic molecules on the surface of the nanoparticles. Further studies including temperature-dependent magnetization and coercivity measurements were performed by PPMS and ESR, confirming the soft magnetic characteristics of synthesized FeNPs. Additionally, the dose-dependent toxicity and anti-cancerogenic effects of the FeNPs were screened towards the glioma cancer line (C6) and fibroblast cell line (L929) in vitro using an MTT assay. After 24 h of treatment, inhibitory concentration IC50 values of 26.51 µg/mL (l929) and 10.73 µg/mL (C6) were determined, respectively. These results suggest the potential of the synthesized FeNPs in developing new biocompatible systems for diagnostic and therapeutic purposes. This study contributes to the growing demand for research in nanotechnology by offering a sustainable and effective green synthesis method for FeNPs, expanding their potential applications in nanomedicine.

Clean and Efficient Green Protocol of N,N'-Bis(2-(arylazo)-2-(aroyl)vinyl)ethane-1,2-diamines in Aqueous Medium without Catalyst: Synthesis and Photophysical Characterization.

An interesting platform for the construction of novel N,N'-bis(2-(arylazo)-2-(aroyl)vinyl)ethane-1,2-diamines is reported in this work. These bis-arylazo compounds were assembled based on the reaction of ethylenediamine with various 2-arylhydrazono-3-oxopropanals in aqueous conditions under both conventional stirring and microwave conditions at ambient temperature. The factors affecting the optimization conditions were intensively practiced. The structures of the new products were established from their spectroscopic analyses and X-ray single crystals. The photophysical behavior of the bis-arylazo derivatives was examined. The UV-vis spectra showed maximum absorption band in the range of 348-383 nm with molar extinction coefficients ranging from 0.89 × 104 to 4.02 × 104 M-1 cm-1. The highest molar absorptivity coefficient (∼45 × 103 M-1 cm-1) was observed in CHCl3 solvent. The fluorescence properties showed that some compounds were interesting fluorophore materials with high Stokes shifts. The photoluminescence study of some compounds was promising, with maximal emission peaks ranging between 417-436 nm.

Rapid Micro-Propagation of Disease-Free Hemp (Cannabis sativa L.) to Improve Industrial Production

Hemp (Cannabis sativa L.) is widely used in industrial production due to its pharmacological properties, particularly cannabidiol (CBD). For commercial production, it is essential to have a large-scale propagation that is consistently disease-free and rapid. Thus, this study aims to establish a protocol for exponentially increasing the amount of high CBD hemp variety CA-UP1 by nodal segment via tissue culture method. Initially, with 10-minute surface sterilization with 0.1 % HgCl2, the microbial contamination rate was reduced to its lowest level (approximately 16.67 %) within 7 days. The nodal segments exhibited optimal response to MS media supplemented with 0.5 mg/L TDZ, resulting in a 100 % shoot multiplication rate. The average number of shoots per explant was 4.7 ± 1.57, and the average shoot height was 2.30 ± 0.42 cm at 4 weeks. Following the induction of elongation in MS medium supplemented with charcoal, the seedlings were acclimatized and dipped in a 1,000 ppm IBA solution mixed with talcum powder. The cultivation resulted in a 100 % rooting rate, with an average of 5.6 ± 1.94 roots/explant, an average root length of 5.78 ± 1.96 cm, and an average explant height of 4.32 ± 1.52 cm. The tissue culture protocol can produce over 190 times the quantity of hemp plants compared with the stem cutting technique. The researchers anticipate that this micropropagation protocol will be useful as a rapid and economical alternative for the industrial production of effective C. sativa L. HIGHLIGHTS A 10-minute surface cleaning protocol with a minimal microbiological contamination rate of 16.67 % in the nodal segment. Thidiazuron (TDZ) can stimulate the most significant increase in shoot growth in Cannabis sativa L. variety CA-UP1 when grown on a semi-solid medium. Dispensing talcum powder combined with IBA results in a 70 - 100 % survival percentage by effectively preventing root during the acclimation stage. The following procedures can be implemented micropropagation of hemp for the production of a large quantity of high-quality, disease-free hemp plants with approximately 190 times more than stem cutting method. GRAPHICAL ABSTRACT

Presence of Methicillin-Resistant Staphylococci and Carbapenemase-Positive Acinetobacter Isolates on Surfaces in German Dog Daycare Facilities and Correlation with Cleaning Practices.

Many bacteria, including methicillin-resistant staphylococci and opportunistic pathogens such as Acinetobacter (A.) species, in particular members of the A. calcoaceticus-A. baumannii (Acb) complex, are known to survive in environmental settings. This increases the risk of bacterial spreading and transmission to animals and humans, especially in institutions with a high animal population density. This study aimed to identify the presence of multidrug-resistant (MDR) staphylococci and Acinetobacter species in dog daycare facilities (DDFs). The surfaces of 16 DDFs were sampled and information about cleaning practices was obtained. After microbial identification, the detected isolates were investigated by multiplex PCR for antimicrobial resistance genes. In 200 location samples, 38 staphylococci and 109 Acinetobacter spp. isolates were identified. Methicillin-resistant genes were confirmed in 18 staphylococci isolates from four DDFs, including Staphylococcus (S.) equorum, S. saprophyticus, S. cohnii, S. lentus, and S. haemolyticus. Eight A. radioresistens isolates comprising the blaOXA-23 carbapenemase gene and seventeen isolates belonging to the Acb complex were also isolated. This is the first investigation for MDR pathogens in DDFs, a close human-animal interaction environment. Though the role of DDFs in the transmission and spreading of MDR bacteria is not known, the findings should contribute to the public awareness and underscore the necessity of adequate cleaning protocols.

Cleaning and Disinfection of Surfaces in a COVID-19 Respiratory Syndrome Unit: A Quasi-Experimental Study

Objective: This study aimed to assess the impact of an educational intervention on the cleaning and disinfection processes within a respiratory syndrome unit, serving as a designated facility for COVID-19 patients. Methods: A quasi-experimental design was employed, incorporating a pre-intervention and postintervention assessment. The evaluation of surfaces involved various monitoring techniques, including Adenosine Triphosphate (ATP) testing, colony-forming unit analysis, and visual inspections. All statistical analyses were conducted at a significance level of 5% (p < 0.05). Results: Following the implementation of the educational intervention, a notable reduction in surface contamination rates was observed. Significant improvements were noted for specific surfaces when utilizing the ATP testing method, including benchtops (p = 0.030), mattresses (p = 0.014), doorknobs (p = 0.014), and armchairs (p = 0.014). Furthermore, a decrease in the total count of aerobic bacteria was observed for benchtops (p = 0.014), mattresses (p = 0.014), and doorknobs (p = 0.014). Visual inspection results also indicated enhancements, with approval rates for benchtops, armchairs, and mattresses rising from 0% before the intervention to 37.5% afterward. Conclusion: The findings of this study demonstrate substantial improvements in approval rates following the implementation of the educational intervention. Additionally, this research provides valuable insights for the development of ongoing educational initiatives for the healthcare team, incorporating evaluation and feedback mechanisms as well as updates to cleaning and disinfection protocols.

Successful control of an environmental reservoir of NDM-producing Klebsiella pneumoniae associated with nosocomial transmissions in a low-incidence setting

BackgroundThe hospital wastewater system has been reported as a source of nosocomial acquisition of carbapenemase producing Enterobacteriaceae (CPE) in various settings. Cleaning and disinfection protocols or replacement of contaminated equipment often fail to eradicate these environmental reservoirs, which can lead to long-term transmission of CPE. We report a successful multimodal approach to control a New Delhi metallo-beta-lactamase positive Klebsiella pneumoniae (NDM-KP) nosocomial outbreak implicating contamination of sink traps in a low-incidence setting.MethodsFollowing the incidental identification of NDM-KP in a urine culture of an inpatient, we performed an epidemiological investigation, including patient and environmental CPE screening, and whole genome sequencing (WGS) of strains. We also implemented multimodal infection prevention and control (IPC) measures, namely the isolation of cases, waterless patient care, replacement of contaminated P-traps and connecting pieces, and bleach and steam disinfection of sinks for 6 months, followed by patient and environmental screenings for eradication.ResultsBetween February and May 2022, five NDM-KP cases were identified in an eight-bed neurosurgical intermediate care unit. Among the eight sink traps of the unit, three were positive for NDM-KP. Patient and environmental isolates belonged to multilocus sequence typing ST-268. All isolate genomes were genetically very similar suggesting cross-transmission and a potential role of the environment as the source of transmissions. Following the introduction of combined IPC measures, no new case was subsequently detected and sink traps remained negative for NDM-KP within 6 months after the intervention.ConclusionThe implementation of multimodal IPC measures, including waterless patient care combined with the replacement and disinfection of P-traps and connecting pieces, was successful in the control of NDM-KP after eight months. In a low-incidence setting, this approach has made it possible to pursue the objective of zero transmission of carbapenemase-producing Enterobacteriaceae (CPE).

Modelling a Western Lifestyle in Mice: A Novel Approach to Eradicating Aerobic Spore-Forming Bacteria from the Colonic Microbiome and Assessing Long-Term Clinical Outcomes.

The environmentally acquired aerobic spore-forming (EAS-Fs) bacteria that are ubiquitous in nature (e.g., soil) are transient colonisers of the mammalian gastro-intestinal tract. Without regular exposure, their numbers quickly diminish. These species of bacteria have been suggested to be essential to the normal functioning of metabolic and immunogenic health. The modern Western lifestyle restricts exposure to these EAS-Fs, possibly explaining part of the pathogenesis of many Western diseases. To date, the only animal studies that address specific microbiome modelling are based around germ-free animals. We have designed a new animal model that specifically restricts exposure to environmental sources of bacteria. A new protocol, termed Super Clean, which involves housing mice in autoclaved individually ventilated cages (IVCs), with autoclaved food/water and strict ascetic handling practice was first experimentally validated. The quantification of EAS-Fs was assessed by heat-treating faecal samples and measuring colony-forming units (CFUs). This was then compared to mice in standard conditions. Mice were housed in their respective groups from birth until 18 months. Stool samples were taken throughout the experiment to assess for abundance in transiently acquired environmental bacteria. Clinical, biochemical, histological, and gene expression markers were analysed for diabetes, hypercholesterolaemia, obesity, inflammatory bowel disease, and non-alcoholic fatty liver disease (the "diseases of the West"). Our results show that stringent adherence to the Super Clean protocol produces a significantly decreased abundance of aerobic spore-forming Bacillota after 21 days. This microbiomic shift was correlated with significantly increased levels of obesity and impaired glucose metabolism. There was no evidence of colitis, liver disease or hypercholesterolaemia. This new murine model successfully isolates EAS-Fs and has potential utility for future research, allowing for an investigation into the clinical impact of living in relative hygienic conditions.

Chemical Cleaning Techniques for Fouled RO Membranes: Enhancing Fouling Removal and Assessing Microbial Composition.

Membrane fouling, a major challenge in desalination, is addressed in this study by investigating three different chemical cleaning protocols (A, B, and C) targeting fouled reverse osmosis (RO) membranes and microbial community composition. Cleaning protocols A and B involve different chemical treatments selected based on preliminary tests and literature review, while protocol C follows the manufacturer's standard recommendation. Membrane morphology, foulant composition, and microbial community variability in fouled, virgin, and cleaned membranes are studied. Effective biofilm removal is observed across all protocols using scanning electron microscopy (SEM), while spectroscopic techniques highlight interactions between foulants and membranes. Importantly, a critical gap in understanding how cleaning strategies influence microbial communities on membranes is addressed. Shifts in dominant bacterial phyla (Proteobacteria, Firmicutes, and Actinobacteria) after cleaning are identified through 16S rRNA amplicon sequencing. Cleaning A showed the best results in reducing microbial counts and restoring composition similar to virgin membranes. Additionally, chemical treatment increased dominance of resistant genera such as Staphylococcus, Bacillus, Citrobacter, and Burkholderia. This study emphasizes the necessity for tailored fouling cleaning strategies for RO membranes, with Cleaning A is a promising solution, paving the way for enhanced water purification technologies.

Characterization and long-read sequencing of biofilms formed by the microbiota present on inert surfaces in poultry slaughterhouses

Cross-contamination from inert slaughterhouse surfaces is among the main sources of contamination of poultry. The objective of the research reported here was to characterize the biofilms formed by the microbiota present on various surfaces in two poultry slaughterhouses in north-western Spain. Forty-four samples (22 from each slaughterhouse) were taken by swab rubbing at different points along the processing line (from stunning to cutting). The microbiota on all surfaces was able to form biofilms, which were studied by scanning confocal laser microscopy. The total biovolume in the observation field of 16,078.24 μm2 ranged from 22,106.8 ± 5544.3 μm3 to 414,229.6 ± 1621.0 μm3. Average values were higher in abattoir A than in abattoir B, with significant differences (P < 0.05) between surfaces. The percentage of biovolume of Gram-positive bacteria ranged between 0.02 % and 5.38 %. The highest percentages of Gram-positive bacteria were detected towards the beginning of the processing line. The microbiota of the biofilms was identified using long-read sequencing techniques (Oxford Nanopore). The predominant genera (found in >50.0 % of the biofilms) were Pseudomonas, Citrobacter, Klebsiella, Serratia, Escherichia, Enterobacter, Stenotrophomonas, Salmonella, Shewanella, Acinetobacter and Aeromonas. In addition, some pathogenic bacteria were detected, including Salmonella (31 surfaces), Yersinia enterocolitica (12), Escherichia coli O157:H7 (6), Campylobacter spp. (4) and Listeria monocytogenes (3). This research work has permitted identification of the most contaminated surfaces in poultry abattoirs and can serve as a starting point for the design of more effective cleaning and disinfection protocols.

Use of image analysis in the evaluation of radicular nodules in chickpeas

The use of advanced computational systems facilitates the application of a wide range of statistical techniques, available in open-source format, to perform analyses of substantial complexity in biological systems, particularly in the field of plant biology. The aim of this study is to demonstrate the application of image analysis in the evaluation of root nodules in Cicer arietinum plants. The research was conducted in the field, where roots were collected, subjected to rigorous cleaning protocols and subsequently photographed under precisely controlled studio conditions. This photographic process was performed using equipment configured with meticulous parameter settings. Subsequently, image analyses were performed using the statistical software package, R. Parameters of interest were quantified, including metrics such as root area, nodule area, the proportional representation of nodules in relation to the total root mass and the absolute count of nodules present. A critical comparison between the proposed analytical methodology and conventional approaches evidenced a substantial improvement in efficiency, thus highlighting the robustness and validity of this analytical framework for the outlined research objectives. Therefore, the developed methodology has significant potential to facilitate accurate and comprehensive analyses of nodules and root systems, thus making a notable contribution to fostering a deeper understanding and exploration of plant-microorganism interactions. Furthermore, this methodological advancement has the potential to contribute to reducing operational costs and optimizing the time spent on such meticulous evaluative undertakings.

Investigating the impact of different cleaning techniques on bond strength between resin cement and zirconia and the resulting physical and chemical surface alterations.

To evaluate the effect of cleaning methods and thermocycling on the micro-tensile bond strength between resin cement and contaminated zirconia and to characterize the physicochemical alterations at the zirconia surface resulting from contaminants and subsequent application of cleaning methods. Thirty-two alumina air-abraded zirconia blocks were divided into eight groups: (i) uncontaminated control followed by methacryloyloxydecyl dihydrogen phosphate (MDP) primer (G-Multi Primer) application (CON). In groups ii-viii, the blocks were contaminated with saliva and silicone disclosing agents, followed by cleaning as follows: (ii) MDP primer applied, followed by contamination (GMP1); (iii) MDP primer applied before and after contamination (GMP2); (iv) cleaning with alumina air-abrasion (APA); (v) cleaning with sodium hypochlorite (NaOCl); (vi) cleaning with Ivoclean (IVC); (vii) cleaning with ZirClean (ZC); and (viii) cleaning with Katana Cleaner (KC). After cleaning, the zirconia blocks in groups iv-viii were applied with MDP primer. The blocks in each group were cemented together with resin cement (G-Cem Linkforce). Subsequently, each bonded zirconia block was sectioned using a water-cooled diamond saw into microsticks (1×1×9 mm3). Micro-tensile bond strength was measured after either 24h or 10,000 thermal cycles (n = 20/subgroup). Data were analyzed using two-way analysis of variance (ANOVA), followed by one-way ANOVA, and Tukey's post-hoc test. The contact angle measurements, energy dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared (FTIR) spectrometer were used for physiochemical evaluation. After 24h of water storage, the highest bond strength was observed in the CON, NaOCl, APA, and GMP2 groups. After thermocycling, the bond strength significantly decreased in all groups except the GMP2 group, which maintained the highest bond strength. Commercial ceramic cleaning agents (IVC, ZC, and KC groups) exhibited lower bond strengths than the CON groups in both aging conditions. The application of MDP primer before and after contamination is a promising cleaning protocol for removing saliva and silicone disclosing agent contaminants from zirconia surfaces. This approach achieved the highest bond strength and maintained it even after artificial aging through thermocycling.

Effective removal of aged protective coatings from natural heritage in yunyang using strong peelable hydrogels via enhanced interfacial interactions

Organic polymers such polyacrylates, silicones have been used to protect stone-based heritages. However, polymers degrade obviously with time which may lead to secondary damages to heritages. Removal of previously applied but now degraded polymers on stone surface becomes necessary for the long-term preservation of stone heritages. Current cleaning protocol is mainly based on dissolving or extraction of aged polymers by organic liquid, whose kinetics is dominated by the slow diffusion and dissolving processes at the interfaces. Such cleaning process is very time consuming and becomes almost not applicable in large area cleaning. In this work, peelable PVA-borate hydrogels are developed. Organic solvents are introduced to tune gel's mechanical strength and its interfacial adhesion strength. Aged polymer coating can be removed easily by mechanical peeling when appropriate adhesion forces between the gel and aged polymer coating are achieved. Such cleaning protocol has been successfully applied on a fossil wall around 1200 m2. Details, precautions and limitations of this protocol is discussed in this work.

The effectiveness of a school-based protocol for environmental cleaning and disinfection during a pandemic: a randomized controlled pilot study

BackgroundSince no specific environmental cleaning instructions and methods have been developed for schools to tackle pandemics, and cleaning methods, this study aims to investigate the feasibility of a new effective school cleaning protocol in reducing the environmental contamination in kindergarten and primary school settings.MethodsThis study implemented a cluster randomized controlled trial with three-arms, namely two intervention arms - groups A and B, and one control arm – group C. The first intervention arm included the cleaning staff who would participate in an educational workshop and be equipped with disposable wipes, while the second arm, group B, participated in the educational workshop only. The third arm, group C, received no treatments.Results1080 sample points were collected from pre-determined sites in the study within the 6 schools. At the 2-week follow-up post-intervention assessment, all sites were found to be clean for group A that used disposable wipes, while group B, without disposable wipes, were found to have left more sites contaminated. Staphylococcus aureus was found in the sites cleaned by group C.ConclusionBased on the findings in this pilot study, a further study at a larger scale focusing on the education program with enhancement and use of the cleaning protocol can be conducted to train cleaning staff for effective environmental cleaning in a school setting.

Exploring Basalt: A Methodological Framework for Analysing Wear Traces on Basalt Tools

Basalt is a widely used raw material for tool manufacture at prehistoric sites, but a unified methodology for assessing how hominfins used basalt in prehistory is lacking. A comprehensive experimental investigation of basalt tools is, thus, necessary to establish a reliable methodological framework that can be used to explore the functional properties of archaeological basalt assemblages.The aim of this study is to contribute to the development of a methodological framework for the analysis of use-wear on basalt tools. Basalt, characterised by its distinct mechanical and structural properties and unique response to mechanical stress, requires specialised treatment and investigation.To address this, our basalt varieties were characterised using SEM–EDS analysis. Sequential experiments were conducted, using the experimental basalt tools in different activities, including butchery, hide, bone and woodworking to determine use-wear formation patterns. Subsequentially, various analytical tools, including optical and scanning electron microscopes, were used to analyse macro- and micro-wear traces on basalt.Our results provide useful information on methodological aspects of use-wear formation on basalt. The inclusion of detailed cleaning and experimental protocols enhanced the robustness of our methodology. Furthermore, the combined utilisation of various microscopes enabled to compile a comprehensive and complementary information on such a complex raw material such as basalt and to characterise thoroughly the diagnostic features of the micro-wear traces (e.g. edge damage, rounding, polish).

Swine farm environmental microbiome: exploring microbial ecology and functionality across farms with high and low sanitary status.

Stringent regulations in pig farming, such as antibiotic control and the ban on certain additives and disinfectants, complicate disease control efforts. Despite the evolution of microbial communities inside the house environment, they maintain stability over the years, exhibiting characteristics specific to each type of production and, in some cases, unique to a particular company or farm production type. In addition, some infectious diseases are recurrent in specific farms, while other farms never present these diseases, suggesting a connection between the presence of these microorganisms in animals or their environment. Therefore, the aim of this study was to characterise environmental microbiomes of farms with high and low sanitary status, establishing the relationships between both, health status, environmental microbial ecology and its functionality. For this purpose, 6 pig farms were environmentally sampled. Farms were affiliated with a production company that handle the majority of the pigs slaughtered in Spain. This study investigated the relationship among high health and low health status farms using high throughput 16S rRNA gene sequencing. In addition, to identify ecologically relevant functions and potential pathogens based on the 16S rRNA gene sequences obtained, functional Annotation with PROkaryotic TAXa (FAPROTAX) was performed. This study reveals notable differences in microbial communities between farms with persistent health issues and those with good health outcomes, suggesting a need for protocols tailored to address specific challenges. The variation in microbial populations among farms underscores the need for specific and eco-friendly cleaning and disinfection protocols. These measures are key to enhancing the sustainability of livestock farming, ensuring safer products and boosting competitive edge in the market.