Exploration on Optimized Control Way of D-Amino Acid for Efficiently Mitigating Membrane Biofouling of Membrane Bioreactor

The thorny issue of membrane biofouling in membrane bioreactors (MBR) calls for new effective control measures. Herein, D-amino acid (DAA) was employed to mediate MBR membrane biofouling by inhibiting biofilm information and disintegrating formed biofilm. Different DAA control ways involving membrane property, DAA-adding timing, and DAA-control mode were explored through experiments and the multiple linear regression model and the response surface methodology. The optimized DAA control ways were acquired, involving DAA used as an active agent, and the DAA-adding timing of 4 h cultured before running, as well as both hydrophilic and hydrophobic membrane, resulting in an approximately 40.24% decrease in the membrane biofouling rate in comparison with the conventional MBR. DAA is an efficient membrane biofouling mediating approach for MBR under optimized control ways combination and a facile solution for solving membrane biofouling in actual membrane systems.

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Membrane bioreactors for wastewater treatment: A review of microbial quorum sensing and quenching to control membrane biofouling based on engineering quorum quenching bacteria

E3S Web of Conferences ◽

10.1051/e3sconf/202019404026 ◽

2020 ◽

Vol 194 ◽

pp. 04026

Author(s):

Xinmeng Jiao ◽

Kang Xie ◽

Liping Qiu

Keyword(s):

Wastewater Treatment ◽

Quorum Sensing ◽

Membrane Fouling ◽

Membrane Bioreactor ◽

Membrane Surface ◽

Quorum Quenching ◽

Membrane Bioreactors ◽

Practical Application ◽

Membrane Biofouling ◽

New Strategy

Membrane bioreactor (MBR) is a kind of reputable and prospective technology for wastewater treatment and reformation applications. However, membrane fouling caused by the formation of biofilm on the membrane surface, especially biofouling, is a major obstacle that limits the energy-saving operation and maintenance of the membrane bioreactor (MBR). Microbial communication (known as Quorum Sensing (QS)) is the cause of this fouling phenomenon. A new strategy called Quorum Quenching (QQ) seems to have been successfully used for biological pollution control in wastewater treatment MBR. This review summarizes the latest findings regarding membrane fouling, QS mechanisms and QQ applications. We discussed the opportunities for further practical application of self-cleaning engineering QQ bacteria in MBR.

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Clinical and Laboratory Studies of Nosocomial Staphylococcus aureus Resistant to Methicillin and Aminoglycosides

Infection Control ◽

10.1017/s0195941700056149 ◽

1982 ◽

Vol 3 (3) ◽

pp. 224-229 ◽

Cited By ~ 11

Author(s):

Bonnie V. Bock ◽

Karen Pasiecznik ◽

Richard D. Meyer

Keyword(s):

Staphylococcus Aureus ◽

Intensive Care ◽

Susceptibility Testing ◽

Phage Type ◽

Active Agent ◽

Underlying Disease ◽

Control Measures ◽

Effective Control ◽

Laboratory Studies ◽

Vancomycin Therapy

AbstractA methicillin/aminoglycoside-resistant strain of Staphylococcus aureus (MARS) was likely introduced by transfer of a patient from another hospital. Over the next year, 20 other patients were colonized or infected with MARS of the same phage type, although antibiograms varied. Affected patients usually had serious underlying disease and were in intensive care units. Vancomycin therapy was frequently delayed and MARS may have contributed to the death of some patients. The mode of spread was not definitively delineated, but two nurses were found to be colonized. Institution of isolation procedures was difficult, but the problem gradually waned.Susceptibility testing showed vancomycin to be the most active agent. Synergy studies showed no consistent effect of combining methicillin with an aminoglycoside. This experience illustrates the problem of MARS spread between hospitals and wards, the need for institution of effective control measures, and consideration of early empiric use of vancomycin.

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Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

10.2196/preprints.21321 ◽

2020 ◽

Author(s):

Lukman Olagoke ◽

Ahmet E. Topcu

Keyword(s):

Control Measure ◽

Control Measures ◽

World Health ◽

Mitigation Measures ◽

Effective Control ◽

The World ◽

Decision Making Processes ◽

And Performance ◽

Health Organization ◽

The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

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Effectiveness of Epidemic Preventive Policies and Hospital Strategies in Combating COVID-19 Outbreak in Taiwan

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18073456 ◽

2021 ◽

Vol 18 (7) ◽

pp. 3456

Author(s):

Ting Wan Tan ◽

Han Ling Tan ◽

Man Na Chang ◽

Wen Shu Lin ◽

Chih Ming Chang

Keyword(s):

Mortality Rate ◽

Incidence Rate ◽

Risk Ratio ◽

Early Stage ◽

Control Measures ◽

Polymerase Chain Reaction Test ◽

Effective Control ◽

Nasopharyngeal Swab ◽

Preventive Strategies ◽

Epidemic Control

(1) Background: The implementation of effective control measures in a timely fashion is crucial to control the epidemic outbreak of COVID-19. In this study, we aimed to analyze the control measures implemented during the COVID-19 outbreak, as well as evaluating the responses and outcomes at different phases for epidemic control in Taiwan. (2) Methods: This case study reviewed responses to COVID-19 and the effectiveness of a range of control measures implemented for epidemic control in Taiwan and assessed all laboratory-confirmed cases between 11 January until 20 December 2020, inclusive of these dates. The confirmation of COVID-19 infection was defined as the positive result of a reverse-transcriptase–polymerase-chain-reaction test taken from a nasopharyngeal swab. Test results were reported by the Taiwan Centers for Disease Control. The incidence rate, mortality rate, and testing rate were compiled, and the risk ratio was provided to gain insights into the effectiveness of prevention measures. (3) Results and Discussion: This study presents retrospective data on the COVID-19 incidence rate in Taiwan, combined with the vital preventive control measures, in a timeline of the early stage of the epidemic that occurred in Taiwan. The implementation of multiple strategy control measures and the assistance of technologies to control the COVID-19 epidemic in Taiwan led to a relatively slower trend in the outbreak compared to the neighboring countries. In Taiwan, 766 confirmed patients were included, comprised of 88.1% imported cases and 7.2% local transmission cases, within the studied period. The incidence rate of COVID-19 in Taiwan during the studied period was 32 per million people, with a mortality rate of 0.3 per million people. Our analysis showed a significantly raised incidence risk ratio in the countries of interest in comparison to Taiwan during the study period; in the range of 1.9 to 947.5. The outbreak was brought under control through epidemic policies and hospital strategies implemented by the Taiwan Government. (4) Conclusion: Taiwan’s preventive strategies resulted in a drastically lower risk for Taiwan nationals of contracting COVID-19 when new pharmaceutical drug or vaccines were not yet available. The preventive strategies employed by Taiwan could serve as a guide and reference for future epidemic control strategies.

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Molecular Identification of Mushroom Species in Italy: An Ongoing Project Aimed at Reinforcing the Control Measures of an Increasingly Appreciated Sustainable Food

Sustainability ◽

10.3390/su13010238 ◽

2020 ◽

Vol 13 (1) ◽

pp. 238

Author(s):

Alice Giusti ◽

Enrica Ricci ◽

Laura Gasperetti ◽

Marta Galgani ◽

Luca Polidori ◽

...

Keyword(s):

Selection Process ◽

Winning Strategy ◽

Control Measures ◽

Effective Control ◽

Mushroom Poisoning ◽

Clinical Samples ◽

Similar Species ◽

Mushroom Species ◽

Ongoing Research ◽

Genotypic Analysis

Proper investment in mushroom production (farming and wild mushroom picking activities) may represent a winning strategy for many countries, including Italy, to better face the problems of food security and environmental impact, and to break away from imports, enhancing the local products. However, the risk related to the consumption of poisoning species requires governments to implement or reinforce effective control measures to protect consumers. Mushroom identification by phenotype observation is hardly applicable if morphologically-similar species, non-whole specimens, or clinical samples are involved. Genotypic analysis is a valid alternative. An ongoing research project involving the Experimental Zooprophylactic Institute of Lazio and Tuscany, the regional Mycological Inspectorate, the Tuscany Mycological Groups Association, and the Department of Veterinary Sciences of the University of Pisa aims to reinforce the collaboration among institutions for the management of mushroom poisoning. The core’s project aims to develop an internal genetic database to support the identification of wild and cultivated mushroom species in the Italian territory. The database will include Internal Transcribed Spacer (ITS) sequences retrieved from official databases (the NCBI GenBank and the BOLD system) which are considered to be reliable, after a proper selection process, and sequences from specimens collected directly and identified by expert mycologists. Once it is validated, the database will be available and further implementable by the official network of national laboratories.

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Timing and Route of Contamination of Patient Rooms With Healthcare-Associated Pathogens

Infection Control and Hospital Epidemiology ◽

10.1017/ice.2020.1066 ◽

2020 ◽

Vol 41 (S1) ◽

pp. s412-s412

Author(s):

Sarah Redmond ◽

Jennifer Cadnum ◽

Basya Pearlmutter ◽

Natalia Pinto Herrera ◽

Curtis Donskey

Keyword(s):

Acute Care Hospital ◽

Current Control ◽

Pathogen Transmission ◽

Control Measures ◽

Effective Control ◽

Portable Devices ◽

Care Hospital ◽

Spa Typing ◽

Persistent Problem ◽

Healthcare Associated

Background: Transmission of healthcare-associated pathogens such as Clostridioides difficile and methicillin-resistant Staphylococcus aureus (MRSA) is a persistent problem in healthcare facilities despite current control measures. A better understanding of the routes of pathogen transmission is needed to develop effective control measures. Methods: We conducted an observational cohort study in an acute-care hospital to identify the timing and route of transfer of pathogens to rooms of newly admitted patients with negative MRSA nares results and no known carriage of other healthcare-associated pathogens. Rooms were thoroughly cleaned and disinfected prior to patient admission. Interactions of patients with personnel and portable equipment were observed, and serial cultures for pathogens were collected from the skin of patients and from surfaces, including those observed to come in contact with personnel and equipment. For MRSA, spa typing was used to determine relatedness of patient and environmental isolates. Results: For the 17 patients enrolled, 1 or more environmental cultures became positive for MRSA in rooms of 10 patients (59%), for C. difficile in rooms of 2 patients (12%) and for vancomycin-resistant enterococci (VRE) in rooms of 2 patients (12%). The patients interacted with an average of 2.4 personnel and 0.6 portable devices per hour of observation. As shown in Figure 1, MRSA contamination of the floor occurred rapidly as personnel entered the room. In a subset of patients, MRSA was subsequently recovered from patients’ socks and bedding and ultimately from the high-touch surfaces in the room (tray table, call button, bedrail). For several patients, MRSA isolates recovered from the floor had the same spa type as isolates subsequently recovered from other sites (eg, socks, bedding, and/or high touch surfaces). The direct transfer of healthcare-associated pathogens from personnel or equipment to high-touch surfaces was not detected. Conclusions: Healthcare-associated pathogens rapidly accumulate on the floor of patient rooms and can be transferred to the socks and bedding of patients and to high-touch surfaces. Healthcare facility floors may be an underappreciated source of pathogen dissemination not addressed by current infection control measures.Funding: NoneDisclosures: None

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Genome sequence, transcriptome, and annotation of rodent malaria parasite Plasmodium yoelii nigeriensis N67

BMC Genomics ◽

10.1186/s12864-021-07555-9 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Cui Zhang ◽

Cihan Oguz ◽

Sue Huse ◽

Lu Xia ◽

Jian Wu ◽

...

Keyword(s):

Dna Sequences ◽

Malaria Parasite ◽

Vaccine Development ◽

De Novo ◽

Gene Families ◽

Plasmodium Yoelii ◽

Control Measures ◽

Effective Control ◽

Malaria Parasites ◽

Rodent Malaria

Abstract Background Rodent malaria parasites are important models for studying host-malaria parasite interactions such as host immune response, mechanisms of parasite evasion of host killing, and vaccine development. One of the rodent malaria parasites is Plasmodium yoelii, and multiple P. yoelii strains or subspecies that cause different disease phenotypes have been widely employed in various studies. The genomes and transcriptomes of several P. yoelii strains have been analyzed and annotated, including the lethal strains of P. y. yoelii YM (or 17XL) and non-lethal strains of P. y. yoelii 17XNL/17X. Genomic DNA sequences and cDNA reads from another subspecies P. y. nigeriensis N67 have been reported for studies of genetic polymorphisms and parasite response to drugs, but its genome has not been assembled and annotated. Results We performed genome sequencing of the N67 parasite using the PacBio long-read sequencing technology, de novo assembled its genome and transcriptome, and predicted 5383 genes with high overall annotation quality. Comparison of the annotated genome of the N67 parasite with those of YM and 17X parasites revealed a set of genes with N67-specific orthology, expansion of gene families, particularly the homologs of the Plasmodium chabaudi erythrocyte membrane antigen, large numbers of SNPs and indels, and proteins predicted to interact with host immune responses based on their functional domains. Conclusions The genomes of N67 and 17X parasites are highly diverse, having approximately one polymorphic site per 50 base pairs of DNA. The annotated N67 genome and transcriptome provide searchable databases for fast retrieval of genes and proteins, which will greatly facilitate our efforts in studying the parasite biology and gene function and in developing effective control measures against malaria.

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Isolation and characterization of Hena1 – a novel Erwinia amylovora bacteriophage

FEMS Microbiology Letters ◽

10.1093/femsle/fnaa070 ◽

2020 ◽

Vol 367 (9) ◽

Author(s):

Natalya V Besarab ◽

Artur E Akhremchuk ◽

Maryna A Zlatohurska ◽

Liudmyla V Romaniuk ◽

Leonid N Valentovich ◽

...

Keyword(s):

Pathogenic Bacteria ◽

Fire Blight ◽

Antimicrobial Agents ◽

Erwinia Amylovora ◽

Gc Content ◽

Control Measures ◽

Effective Control ◽

Lytic Phage ◽

Trna Genes ◽

Isolation And Characterization

ABSTRACT Fire blight, caused by plant pathogenic bacterium Erwinia amylovora, is one of the most important diseases of Rosaceae plants. Due to the lack of effective control measures, fire blight infections pose a recurrent threat on agricultural production worldwide. Recently, bacterial viruses, or bacteriophages, have been proposed as environmentally friendly natural antimicrobial agents for fire blight control. Here, we isolated a novel bacteriophage Hena1 with activity against E. amylovora. Further analysis revealed that Hena1 is a narrow-host-range lytic phage belonging to Myoviridae family. Its genome consists of a linear 148,842 bp dsDNA (48.42% GC content) encoding 240 ORFs and 23 tRNA genes. Based on virion structure and genomic composition, Hena1 was classified as a new species of bacteriophage subfamily Vequintavirinae. The comprehensive analysis of Hena1 genome may provide further insights into evolution of bacteriophages infecting plant pathogenic bacteria.

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First Description of KPC-2-ProducingKlebsiella oxytocaIsolated from a Pediatric Patient with Nosocomial Pneumonia in Venezuela

Case Reports in Infectious Diseases ◽

10.1155/2014/434987 ◽

2014 ◽

Vol 2014 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Indira Labrador ◽

María Araque

Keyword(s):

Pediatric Patient ◽

Carbapenem Resistance ◽

Control Measures ◽

University Hospital ◽

Conjugative Plasmid ◽

Effective Control ◽

Molecular Tests ◽

The Andes ◽

Clinically Significant ◽

Significant Class

During the last decade, carbapenem resistance has emerged among clinical isolates of the Enterobacteriaceae family. This has been increasingly attributed to the production ofβ-lactamases capable of hydrolyzing carbapenems. Among these enzymes,Klebsiella pneumoniaecarbapenemases (KPCs) are the most frequently and clinically significant class-A carbapenemases. In this report, we describe the first nosocomial KPC-2-producingK. oxytocaisolated from a pediatric patient with pneumonia admitted to the intensive care unit at The Andes University Hospital, Mérida, Venezuela. This strain was resistant to several antibiotics including imipenem, ertapenem, and meropenem but remained susceptible to ciprofloxacin, colistin, and tigecycline. Conjugation assays demonstrated the transferability of all resistance determinants, except aminoglycosides. The isolate LMM-SA26 carried a ~21 kb conjugative plasmid that harbored theblaKPC-2,blaCTX-M-8, andblaTEM-15genes. Although carbapenem resistance in the Enterobacteriaceae is still unusual in Venezuela, KPCs have a great potential to spread due to their localization on mobile genetic elements. Therefore, rapid detection of KPC-carrying bacteria with phenotypic and confirmatory molecular tests is essential to establish therapeutic options and effective control measures.

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Survey and control of small mammal populations on two hardwood plantations in southern Ontario

The Forestry Chronicle ◽

10.5558/tfc50181-5 ◽

1974 ◽

Vol 50 (5) ◽

pp. 181-185 ◽

Cited By ~ 3

Author(s):

Andrew Radvanyi

Keyword(s):

Small Mammal ◽

Late Summer ◽

Control Measures ◽

Effective Control ◽

Southern Ontario ◽

Live Trapping ◽

Surrounding Areas ◽

And Control ◽

Rodent Populations ◽

Ingredient Cost

Live trapping and tagging methods were employed to assess small mammal populations within two hardwood plantations in southern Ontario. Excessive girdling damage in past years to young planted trees necessitated an evaluation of rodent populations and development of effective control measures. The application of an anticoagulant rodenticide to oat groats bait broadcast over the study area at an ingredient cost of approximately three dollars per acre virtually wiped out the small mammals. Reinvasion from surrounding areas was, however, fairly rapid, particularly during late summer. Further research on longer term control measures using poisoned bait feeder stations is recommended.

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