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Water monitoring sensors in industrial, municipal and environmental monitoring are advancing our understanding of science, aid developments in process automatization and control and support real-time decisions in emergency situations. Sensors are becoming smaller, smarter, increasingly specialized and diversified and cheaper. Advanced deployment platforms now exist to support various monitoring needs together with state-of-the-art power and communication capabilities. For a large percentage of submersed instrumentation, biofouling is the single biggest factor affecting the operation, maintenance and data quality. This increases the cost of ownership to the extent that it is prohibitive to maintain operational sensor networks and infrastructures. In this context, the paper provides a brief overview of biofouling, including the development and properties of biofilms. The state-of-the-art established and emerging antifouling strategies are reviewed and discussed. A summary of the currently implemented solutions in commercially available sensors is provided and current trends are discussed. Finally, the limitations of the currently used solutions are reviewed, and future research and development directions are highlighted.
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The excess cement not removed after the cementation of fixed implant-supported restorations may cause loss of peri-implant attachment or adjacent bone. The aims of this study were to evaluate the amount of residual cement at different abutment-crown connection levels and to test the cleaning efficacy of poly-ether-ether-ketone (PEEK) ultrasonic tips after cementation. One implant was placed in an anterior central tooth position 5 mm below the gingival margin in an acrylic model, and 32 stone models were obtained with implant analogs. Abutment heights of 1-2 and 2.5-4 mm were used on the vestibular and lingual sides, respectively. Crowns were cemented and cleaned, and half of the samples were cleaned again using PEEK tips. The abutment-crown suprastructure was then disconnected, and cleaning efficacy was evaluated. Varying amounts of excess cement were found on all specimens except for the PEEK group with abutment-crown connections 1 mm below the gingival margin. An increase of undetected cement remnants was observed when the restoration margins were located deeper subgingivally. Various amounts of excess cement associated with margin location were detected on the abutment-restoration complex despite meticulous cleaning efforts. Ultrasonic PEEK tips were effective at cleaning the cement remnants around implants to a certain depth.
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Implantes Dentários , Prótese Dentária Fixada por Implante , Cimentação , Coroas , Dente Suporte , Cimentos Dentários , Éter , CetonasRESUMO
This study investigated the effect of saliva contamination on chemical changes of ceramic surface as well as the influence of saliva cleaning methods on ceramic-resin bond strength. Saliva was used to contaminate leucite (LGC) and lithium disilicate (LDGC) glass ceramic surfaces. The following cleaning methods were tested: water spray, cleaning with orthophosphoric acid, universal cleaning paste, ultrasonic cleaning with water, re-etching with hydrofluoric acid. Non-contaminated ceramic sample served as control. Chemical analysis of ceramic surfaces was performed using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Shear bond strength (SBS) of ceramics to resin material was tested after 24-hour water storage and after thermocycling. The most effective cleaning method of saliva-contaminated ceramic surface was cleaning LGC surface with orthophosphoric acid or re-etching the LDGC surface with hydrofluoric acid. The application of the following methods resulted in obtaining reliable bond strength.
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Cerâmica/química , Fenômenos Mecânicos , Resinas Compostas/química , Porcelana Dentária/química , Íons/química , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de SuperfícieRESUMO
Research objective was a comparative assessment of quality of sealing of root canals, subjected to a standard method of processing, processing by the laser and processing by LAI equipment, with sealer and the gutta-percha. The study included 20 teeth extracted because of chronic periodontitis and divided into four groups. Root canals were processed according to the traditional protocol using as an irrigant 3% NaOCl and 17% EDTA solution, LAI equipment, the Er laser; Cr; YSGG 2780 nm at a power 1W and 1,5W and sealed up using single protocol by means of an epoxy siler of AH+ and gutta-percha by continuous wave by means of the CalamusDual (DentsplayMaillefer) device. Scanning electronic microscopy was used to study the efficiency of sealing depending on a type of processing. The highest sealing of the obturation material to the canal walls was revealed in teeth processed by the laser at a power of 1.5 W confirmed by lack of emptiness between a material and a dentine. Conventional irrigation protocol did not result in an optimal obturation with the extent of empty spaces up to 13 microns. The results of the pilot research are the basis for more extensive studies.
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Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Cavidade Pulpar , Dentina , Guta-Percha , Irrigantes do Canal Radicular , Preparo de Canal RadicularRESUMO
BACKGROUND: Data cleaning is an important quality assurance in data linkage research studies. This paper presents the data cleaning and preparation process for a large-scale cross-jurisdictional Australian study (the Smoking MUMS Study) to evaluate the utilisation and safety of smoking cessation pharmacotherapies during pregnancy. METHODS: Perinatal records for all deliveries (2003-2012) in the States of New South Wales (NSW) and Western Australia were linked to State-based data collections including hospital separation, emergency department and death data (mothers and babies) and congenital defect notifications (babies in NSW) by State-based data linkage units. A national data linkage unit linked pharmaceutical dispensing data for the mothers. All linkages were probabilistic. Twenty two steps assessed the uniqueness of records and consistency of items within and across data sources, resolved discrepancies in the linkages between units, and identified women having records in both States. RESULTS: State-based linkages yielded a cohort of 783,471 mothers and 1,232,440 babies. Likely false positive links relating to 3703 mothers were identified. Corrections of baby's date of birth and age, and parity were made for 43,578 records while 1996 records were flagged as duplicates. Checks for the uniqueness of the matches between State and national linkages detected 3404 ID clusters, suggestive of missed links in the State linkages, and identified 1986 women who had records in both States. CONCLUSIONS: Analysis of content data can identify inaccurate links that cannot be detected by data linkage units that have access to personal identifiers only. Perinatal researchers are encouraged to adopt the methods presented to ensure quality and consistency among studies using linked administrative data.
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Parto Obstétrico/estatística & dados numéricos , Armazenamento e Recuperação da Informação/métodos , Registro Médico Coordenado/métodos , Assistência Perinatal/estatística & dados numéricos , Pesquisa/estatística & dados numéricos , Abandono do Hábito de Fumar/estatística & dados numéricos , Adulto , Feminino , Humanos , Comportamento Materno/efeitos dos fármacos , Relações Materno-Fetais/efeitos dos fármacos , New South Wales , Gravidez , Abandono do Hábito de Fumar/métodos , Austrália OcidentalRESUMO
Terminal disinfection and daily cleaning have been performed in hospitals in Taiwan for many years to reduce the risks of healthcare-associated infections. However, the effectiveness of these cleaning approaches and dynamic changes of surface microbiota upon cleaning remain unclear. Here, we report the surface changes of bacterial communities with terminal disinfection and daily cleaning in a medical intensive care unit (MICU) and only terminal disinfection in a respiratory care center (RCC) using 16s ribosomal RNA (rRNA) metagenomics. A total of 36 samples, including 9 samples per sampling time, from each ward were analysed. The clinical isolates were recorded during the sampling time. A large amount of microbial diversity was detected, and human skin microbiota (HSM) was predominant in both wards. In addition, the colonization rate of the HSM in the MICU was higher than that in the RCC, especially for Moraxellaceae. A higher alpha-diversity (p = 0.005519) and a lower UniFrac distance was shown in the RCC due to the lack of daily cleaning. Moreover, a significantly higher abundance among Acinetobacter sp., Streptococcus sp. and Pseudomonas sp. was shown in the RCC compared to the MICU using the paired t test. We concluded that cleaning changes might contribute to the difference in diversity between two wards.
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Bactérias/classificação , Bactérias/isolamento & purificação , Desinfecção/métodos , Microbiologia Ambiental , Hospitais , Zeladoria Hospitalar/métodos , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Humanos , Unidades de Terapia Intensiva , Metagenômica , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , TaiwanRESUMO
Perchloroethylene (PERC) is a compound commonly used as a solvent in dry cleaning, despite its severe health and environmental impacts. In recent times chemicals such as hydrocarbons, GreenEarth(®), acetal and liquid carbon dioxide have emerged as less damaging substitutes for PERC, and an even more sustainable water-based wet cleaning process has been developed. We employed a systematic review approach to provide a comprehensive overview of the existing research evidence in the area of sustainable and safe apparel cleaning methods and care. Our review describes traditional professional dry cleaning methods, as well as those that utilise solvents other than PERC, and their ecological attributes. In addition, the new professional wet cleaning process is discussed. Finally, we address the health hazards of the various solvents used in dry cleaning and state-of-the-art solvent residue trace analysis techniques.
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Monitoramento Ambiental , Química Verde/métodos , Lavanderia , Exposição Ocupacional/prevenção & controle , Solventes , Tetracloroetileno/análise , Tetracloroetileno/toxicidade , Água/químicaRESUMO
OBJECTIVE: To determine the influence on shear bond strength and bond failure location of four cleaning methods for orthodontic bracket custom bases. DESIGN: In vitro laboratory study. MATERIAL AND METHODS: Eighty bovine teeth were divided at random into four groups. The bracket custom bases were cleaned with different methods: group 1 with methyl methacrylate monomer, group 2 with acetone, group 3 with 50 µm aluminium oxide particles and group 4 with detergent. The brackets were indirectly bonded onto the teeth with the Sondhi Rapid-Set self-curing adhesive. The maximum required shear bond strength to debond the brackets was recorded. The bond failure location was evaluated using the Adhesive Remnant Index (ARI). One-way analysis of variance (ANOVA) analysis (P<0·05) was used to detect significant differences in the bond strength. Kaplan-Meier survival plots and log-rank test were done to compare the survival distribution between the groups. The Kruskal-Wallis test (P<0·05) was used to evaluate the differences in the ARI scores. RESULTS: The mean bond strengths in groups 1, 2, 3 and 4 were 23·7±5·0, 25·3±5·1, 25·6±3·7 and 25·7±4·2 MPa, respectively. There were no significant statistically differences in either the bond strength or the ARI score between the groups. CONCLUSION: The four custom base-cleaning methods presented the same efficiencies on indirect bond of the brackets; thus, practitioners can choose the method that works best for them.
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Colagem Dentária/métodos , Braquetes Ortodônticos , Acetona/química , Condicionamento Ácido do Dente/métodos , Óxido de Alumínio/química , Animais , Bovinos , Esmalte Dentário/ultraestrutura , Corrosão Dentária/métodos , Detergentes/química , Teste de Materiais , Metilmetacrilato/química , Ácidos Fosfóricos/química , Distribuição Aleatória , Cimentos de Resina/química , Resistência ao Cisalhamento , Solventes/química , Estresse Mecânico , Propriedades de Superfície , Fatores de TempoRESUMO
This study evaluates the practical feasibility of using powdered cellulose microblasting for dry cleaning paper-based printed artworks in a real setting of conservation treatment. The control parameters used for this purpose are the potential morphological changes in the surface, the level of cleanliness achieved, and the amount of residue remaining in the artwork after the treatment. In this study, cleaning of a lithography was conducted entirely with powdered cellulose microblasting. The outcomes were evaluated before and after treatment using optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and spectrophotometry. The results indicate that powdered cellulose microblasting is a feasible and efficient technique for conducting the dry cleaning of printed works on paper without causing morphological changes to their surface. Additionally, it offers significant benefits by enabling precise treatment control, reducing cleaning time, and using materials stable in the long term and compatible with the substrate. Moreover, it mitigates the long-term negative effects caused by synthetic polymer residues from the cleaning materials commonly used in the dry cleaning of paper.
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This in vitro study assessed the effectiveness of three cleaning protocols (air-water spray, 37% phosphoric acid, or Ivoclean) on lithium disilicate restorations' fatigue behavior after try-in paste application, compared to a clean condition. Lithium disilicate discs (IPS e.max CAD, Ivoclar) with Ø-= 12 mm and 1 mm thickness were prepared from prefabricated CAD-CAM blocks, polished, subjected to CAD-CAM milling topography simulation and crystallization. After, etching with 5% hydrofluoric acid and the application of try-in paste (Variolink try-in paste shade white; load of 2.5 N for 5 min) was performed. Discs that received try-in paste were divided into three groups according to the removal protocol: SPRAY - air-water spray for 30 s; HPO - active application of 37% phosphoric acid for 60 s; IVOC - application of Ivoclean for 20 s. Control group (CTRL group) did not receive the try-in paste application. Half of the specimens (n= 15) were tested in the baseline condition (24 h up to 7 days), and the others underwent 25,000 thermal cycles (5 - 55 °C) + 210 days of distilled water storage (37 °C). Additional specimens (n= 3) underwent monotonic testing (1 mm/min). Fatigue testing involved a cyclic fatigue approach (20 Hz, initial load = 100 N - 5000 cycles, step size = 50 N - 10,000 cycles) until a visible crack appeared. Fractographic and topographic analyses were performed. Fatigue data were statistically analyzed with two-way ANOVA, Kaplan-Meier log-rank (Mantel-Cox), and independent t-test (α= 0.05). In the baseline condition, the IVOC group resulted in a superior fatigue behavior compared to the CTRL and SPRAY groups, but similar to the HPO group. The HPO and SPRAY presented a similar fatigue behavior to the CTRL group. It was noticed a decrease in fatigue behavior after aging, which resulted in all the cleaning protocols leading to similar fatigue behavior compared to the CTRL group. On the SPRAY group surface, try-in pastes remnants were noticed. In summary, despite a detrimental impact at baseline conditions, all tested cleaning protocols seem proper to remove the try-in paste from the ceramic's surface in the long-term evaluation.
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Cerâmica , Porcelana Dentária , Ácidos Fosfóricos , Propriedades de Superfície , Teste de Materiais , Cerâmica/química , Desenho Assistido por Computador , Água , Análise do Estresse DentárioRESUMO
Inhalation chambers (ICs) are regularly used in veterinary medicine for the inhalative treatment of chronic respiratory diseases in dogs and cats. Since therapy is usually required lifelong and daily, devices are frequently in use. The aim of this study was to identify bacterial contamination of ICs used for cats and dogs in relation to the applied cleaning measures. Swabs from ICs of 66 cats and 19 dogs with chronic airway diseases were obtained using a standardized protocol and subsequently cultured. A questionnaire was completed by the pet owners regarding the history of their pet's illness and applied device cleaning measures. Overall, 64% (54/86) of the ICs were found to be contaminated; the mask was significantly (p < 0.001) more often contaminated than other device parts. Most cultured bacteria were environmental contaminants; however, some harbored pathogenic potential. Cleaning frequency and method did not significantly influence the presence of contamination. Bacterial contamination of ICs, used for cats and dogs, is common but is not significantly influenced by the type or frequency of cleaning. To avoid potential infection by opportunistic bacteria, the instruction of pet owners regarding the maintenance of the ICs is recommended.
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Background: The temporary cement remaining inside the dental prosthesis can act as a source of microbial colonization and contamination and decrease the final cement retention. Consequently, complete removal of temporary cement before permanent cementation is suggested. This study aimed to assess the effect of different cleaning methods for removing temporary cement on the tensile bond force (TBF) of permanently cemented implant-supported zirconia copings. Materials and Methods: In this in vitro study fifty titanium abutments were screwed onto 50 analogs with 30 Ncm torque into in acrylic resin blocks. Each abutment was scanned separately, and 50 zirconia copings were designed and milled. Permanent resin cement was used to cement copings of control group (N = 10). Copings were divided into two temporary cementation types that in each group, two cleansing methods were used: Temp-S (temporary cement with eugenol and sandblasted after debonding), Samples of the control group were placed in the universal testing machine, and the TBF values were recorded. Samples of the test groups after debonding and cleaning the abutments were subjected to cement with permanent resin cement, aging, and removing. Levene test, two-way analysis of variance (ANOVA), and Tamhane post hoc tests were applied. α = 0.05. Results: The highest and lowest TBF values were found for the TempNE-SU (554.7 ± 31.5 N) and Temp-S (492.2 ± 48 N) groups, respectively. The two groups of isopropyl alcohol baths in ultrasonics in combination with sandblasting showed statistically higher TBF values than the other two groups that used only sandblasting (P < 0.001) and had similar values compared to the control group. Conclusion: Sandblasting combined with immersion in an ultrasonic bath containing isopropyl alcohol resulted in statistically similar values to the values of cementation with resin cement from the beginning. However, cleaning the inside of the copings only by sandblasting method reduced the values of the final retention force in comparison to cement with permanent resin cement from the beginning.
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PURPOSE: Dental implant abutments are defined as medical devices by their intended use. Surfaces of custom-made CAD/CAM two-piece abutments may become contaminated during the manufacturing process in the dental lab. Inadequate reprocessing prior to patient care may contribute to implant-associated complications. Risk-adapted hygiene management is required to meet the requirements for medical devices. METHODS: A total of 49 CAD/CAM-manufactured zirconia copings were bonded to prefabricated titanium bases. One group was bonded, polished, and cleaned separately in dental laboratories throughout Germany (LA). Another group was left untreated (NC). Five groups received the following hygiene regimen: three-stage ultrasonic cleaning (CP and FP), steam (SC), argon-oxygen plasma (PL), and simple ultrasonic cleaning (UD). Contaminants were detected using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) and segmented and quantified using interactive machine learning (ML) and thresholding (SW). The data were statistically analysed using non-parametric tests (Kruskal-Wallis test, Dunn's test). RESULTS: Significant differences in contamination levels with the different cleaning procedures were found (p ≤ 0.01). The FP-NC/LA groups showed the most significant difference in contamination levels for both measurement methods (ML, SW), followed by CP-LA/NC and UD-LA/NC for SW and CP-LA/NC and PL-LA/NC for ML (p ≤ 0.05). EDS revealed organic contamination in all specimens; traces of aluminum, silicon, and calcium were detected. CONCLUSIONS: Chemothermal cleaning methods based on ultrasound and argon-oxygen plasma effectively removed process-related contamination from zirconia surfaces. Machine learning is a promising assessment tool for quantifying and monitoring external contamination on zirconia abutments.
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Implantes Dentários , Humanos , Argônio , Microscopia Eletrônica de Varredura , Aprendizado de Máquina , OxigênioRESUMO
Recent achievement and progress in solar PV play a significant role in controlling climate change. This study reviewed comprehensively electrical characteristics, life cycle of dust, optical characteristics, and different cleaning techniques related to the effect of dust on the performance of PV modules throughout different climate regions of the world. The power maximum power point (MPP) and curve of PV module under the effect of irradiance and temperature were presented. The effect of dust (shading) on the electrical efficiency of PV module was discussed based on soft, partial, and complete (soiling) shading. The physical properties of dust around the globe such as PM10 concentration, dust loading (mgm-2), and fine dust particles concentration were covered and discussed. Reasons behind the accumulation of dust based on, location and installation factors, dust type, and environmental factors. Environmental reasons causing dust and dust removal in accordance with the life cycle of dust was covered in detail. All the reasons that cause the generation, accumulation and removal of dust during its life cycle were explained. All forces responsible for the adhesion phase of the dust life cycle were presented. The effect of dust on PV module transmittance and electrical parameters module were discussed in detail based on physical properties of the dust at its location and installation conditions. Self-cleaning super hydrophobic surfaces based on methods such as solvents, vapor-assisted coating, powder coating, and polymerization were discussed. All cleaning technologies, including self-cleaning technologies, based on the material coating used, and the manufacturing of PV cells was compared. The future prospective for PV technologies and cleaning methods were also covered.
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Poeira , Energia Solar , Poeira/análise , EletricidadeRESUMO
PURPOSE: To explore the level of bioburden and the effectiveness of the manufacturers' recommended cleaning methods on lead apparel in a radiology department. METHODS: A 2-phase experiment at a level II trauma center during a 2-year period assessed the level of bioburden on radiology lead apparel. Adenosine triphosphate swabs and a luminometer were used to measure cleanliness of high-touch areas. Cleanliness was measured before and after 3 cleaning methods were used: cleaning with a mild detergent and water; cleaning with a mild detergent, water, and then a disinfectant; and scrubbing with cleaning wipes. RESULTS: Average bioburden levels exceeded facility thresholds for all areas and types of lead apparel examined. All tested cleaning methods significantly reduced bioburden. DISCUSSION: Monthly cleaning of lead apparel provides improved cleanliness when compared with quarterly cleaning. Daily cleaning of lead apparel that will be used in a sterile environment is recommended. Future research might include examining other patient care and ancillary equipment found in the imaging department for potential bioburden and surveying technologists to examine practices for routine removal of bioburden from equipment. CONCLUSION: Health care professionals must be aware of the potential bioburden on clinical equipment and maintain an effective cleaning practice and schedule to reduce the possibility of spreading infection.
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Infecção Hospitalar , Desinfecção , Trifosfato de Adenosina , Humanos , Controle de InfecçõesRESUMO
(1) Background: The use of removable orthodontic appliances, which is common in early ages, requires careful hygiene, as several different microorganisms are found on their surface during the orthodontic treatment. (2) Methods: Comprehensive electronic searches were conducted up to May 2021. Randomized controlled trials (RCTs) or controlled clinical trials (CCTs), prospective or retrospective, evaluating the efficacy of cleaning and disinfection methods for acrylic removable orthodontic appliances, redacted in the English language, were included. Three independent blinding review authors were involved in study selection, data extraction, and bias assessment. (3) Results: A total of 2491 records were screened and eight studies (six RCTs and two CCTs) fulfilled the inclusion criteria. Among the overall cleaning and disinfection methods described in the included studies, four categories could be defined: liquid antimicrobial agents, commercial tablet cleansers, natural plant extracts and incorporation of quaternary ammonium methacryloxy silicate, all of which demonstrated superior efficacy compared to the placebo/negative control. However, the different methods were not compared with each other. (4) Conclusions: Biofilm control on acrylic orthodontic removable appliances can be performed using the different cleaning and disinfection methods considered in the included studies. Further studies are needed to define the most effective technique. Registration: PROSPERO CRD 42021269297.
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Electrofiltration, an electric field-assisted membrane process, has been a research topic of growing popularity due to its ability to improve membrane performance by providing in situ antifouling conditions in a membrane system. The number of reports on electrofiltration have increased exponentially over the past two decades. These reports explored many innovations, such as novel configurations of an electric field, engineered membrane materials, and interesting designs of foulant compositions and membrane modules. Recent electrofiltration literature focused mainly on compiling results without a comprehensive comparative analysis across different works. The main objective of this critical review is to, first, organize, compare and contrast the results across various electrofiltration studies; second, discuss various types of mechanisms that could be incorporated into electrofiltration and their effect on membrane system performance; third, characterize electrofiltration phenomenon; fourth, interpret the effects of various operational conditions on the performance of electrofiltration; fifth, evaluate the state-of-the-art knowledge associated with modeling efforts in electrofiltration; sixth, discuss the energy costs related to the implementation of electrofiltration; and finally, identify the current knowledge gaps that hinder the transition of the lab-scale observations to industry-scale electrofiltration as well as the future prospects of electrofiltration.
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Milli-channel baffle labyrinths are widely used in drip irrigation systems. They induce a pressure drop enabling drip irrigation. However, with a section thickness that is measured in mm2, they are sensitive to clogging, which reduces the performance and service life of a drip irrigation system. The impact of chlorination (1.5 ppm of free chlorine during 1 h application) and pressure flushing (0.18 MPa) on the biofouling of non-pressure-compensating drippers, fed by real reclaimed wastewater, was studied at lab scale using optical coherence tomography. The effect of these treatments on microbial composition (bacteria and eukaryotes) was also investigated by High-throughput DNA sequencing. Biofouling was mainly observed in the inlet, outlet and return areas of the milli-labyrinth channel from drippers. Chlorination reduced biofilm development, particularly in the mainstream of the milli-labyrinth channel, and it was more efficient when combined with pressure flushing. Moreover, chlorination was more efficient in maintaining water distribution uniformity (CU < 95% compared to less than 85% for unchlorinated lines). It reduced more efficiently the bacterial concentration (≈1 log) and the diversity of the bacterial community in the dripper biofilms compared to the pressure flushing method. Chlorination significantly modified the microbial communities, promoting chlorine-resistant bacteria such as Comamonadaceae or Azospira. Inversely, several bacterial groups were identified as sensitive to chlorination such as Chloroflexi and Planctomycetes. Nevertheless, one month after stopping the treatments bacterial diversity recovered and the chlorine-sensitive bacteria such as Chloroflexi phylum and the Saprospiraceae, Spirochaetaceae, Christensenellaceae and Hydrogenophilaceae families re-emerged in conjunction with the growth of biofouling, highlighting the resilience of the bacteria originating from drippers. Based on PCoA analyses, the structure of the bacterial communities still clustered separately from non-chlorinated drippers, showing that the effect of chlorination was still detectable one month after stopping the treatment.
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Incrustação Biológica , Microbiota , Purificação da Água , Biofilmes , Halogenação , Humanos , Águas ResiduáriasRESUMO
The analysis of hair samples is a common task in forensic investigations. Material transferred to the surface of a hair during a crime challenges the analysis as it has to be removed efficiently. However, the removal of the stain can also lead to a loss of information on stain contributors. DNA analysis of the stain itself might thus be helpful for the forensic investigation. The aim of this study was the examination of different methods to remove common biological surface stains completely from human hair shafts without hampering the parallel DNA extraction of the cleaned hair shaft and the isolated surface stain (blood, saliva, vaginal secretion, semen, and skin flocks). Four different methods of cleaning (water, lysis buffer, swabbing, NaClO) were compared to their cleaning efficiency as well as their success of mtDNA analysis of three hair donors and the original five stains on the hair. In order to test the suitability of this procedure for future analysis methods, a selection of samples were also sequenced with MPS. Additionally, nuclear DNA analysis of the stain DNA was performed using a screening STR assay to test the potential success for detection of a STR profile. The most efficient removal of the stain was achieved using NaClO, however compromising further analysis of the stain DNA. The best results for cleaning and parallel stain analysis were obtained using a swab moistened with 0.5 % SDS for surface cleaning. Especially water failed to remove stains efficiently, leading to a high amount of mixed mtDNA in the DNA extracts. MPS showed an increased sensitivity for detection of minute mixtures.
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Impressões Digitais de DNA , DNA/isolamento & purificação , Cabelo/química , Sequenciamento de Nucleotídeos em Larga Escala , Manejo de Espécimes/métodos , Análise Química do Sangue , Muco do Colo Uterino/química , Humanos , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Saliva/química , Sêmen/química , Análise de Sequência de DNA , Pele/química , Hipoclorito de Sódio , ÁguaRESUMO
PURPOSE: To evaluate the influence of different cleaning methods on the resin bond strength to contaminated translucent 3Y-TZP ceramic. MATERIALS AND METHODS: A total of 133 airborne-particle abraded (0.1 MPa) zirconia specimens were divided into 7 groups. Uncontaminated zirconia specimens were either not cleaned (UN) or cleaned with cleaning paste (Ivoclean) (UP1). After contamination by saliva and blood immersion, zirconia specimens were cleaned using either distilled water rinsing (CW), 99% isopropanol in an ultrasonic bath (CI), cleaning paste according to manufacturer's instructions (CP1), cleaning paste with additional rubbing (CP2), or additional airborne-particle abrasion at 0.1 MPa (CA). Three specimens from each group were examined by x-ray photoelectron spectroscopy (XPS). For each group, sixteen Plexiglas tubes filled with composite resin (Clearfil FII, Kuraray Noritake) were bonded to the zirconia specimens using a primer (Clearfil Ceramic Primer Plus, Kuraray Noritake) and luting composite (Panavia V5, Kuraray Noritake). Before measuring tensile bond strength, specimens were stored in distilled water for 3 or 150 days plus 37,500 thermal cycles. RESULTS: After 3 days, no group showed significantly different TBS compared to the control group UN (p > 0.05). However, groups CW and CI showed significantly lower TBS than all other groups after 150 days (p ≤ 0.05). XPS analysis revealed more organic residue on zirconia surfaces of groups CW and CI than on the other groups. CONCLUSION: Cleaning with the cleaning paste and airborne-particle abrasion were effective in removing saliva and blood contamination and enhancing bond strength.