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Background: Global estimates for cholera annually approximate 4 million cases worldwide with 95,000 deaths. Recent outbreaks, including Haiti and Yemen, are reminders that cholera is still a global health concern. Cholera outbreaks can rapidly induce high death tolls by overwhelming the capacity of health facilities, especially in remote areas or areas of civil unrest. Recent studies demonstrated that stool specimens preserved on filter paper facilitate molecular analysis of Vibrio cholerae in resource limited settings. Specimens preserved in a rapid, low-cost, safe and sustainable manner for sequencing provides previously unavailable data about circulating cholera strains. This may ultimately provide new information to shape public policy response on cholera control and elimination. Methodology/Principal findings: Whole genome sequencing (WGS) recovered close to a complete sequence of the V. cholerae O1 genome with satisfactory genome coverage from stool specimens enriched in alkaline peptone water (APW) and V. cholerae culture isolates, both spotted on filter paper. The minimum concentration of V. cholerae DNA sufficient to produce quality genomic information was 0.02 ng/μL. The genomic data confirmed the presence or absence of genes of epidemiological interest, including cholera toxin and pilus loci. WGS identified a variety of diarrheal pathogens from APW-enriched specimen spotted filter paper, highlighting the potential for this technique to explore the gut microbiome, potentially identifying co-infections, which may impact the severity of disease. WGS demonstrated that these specimens fit within the current global cholera phylogenetic tree, identifying the strains as the 7th pandemic El Tor. Conclusions: WGS results allowed for mapping of short reads from APW-enriched specimen and culture isolate spotted filter papers this provided valuable molecular epidemiological sequence information on V. cholerae strains from remote, low-resource settings. These results identified the presence of co-infecting pathogens while providing rare insight into the specific V. cholerae strains causing outbreaks in cholera-endemic areas. [ABSTRACT FROM AUTHOR]

Background: The use of filter paper as a simple, inexpensive tool for storage and transportation of blood, ‘Dried Blood Spots’ or Guthrie cards, for diagnostic assays is well-established. In contrast, there are a paucity of diagnostic evaluations of dried cerebrospinal fluid (CSF) spots. These have potential applications in low-resource settings, such as Laos, where laboratory facilities for central nervous system (CNS) diagnostics are only available in Vientiane. In Laos, a major cause of CNS infection is Japanese encephalitis virus (JEV). We aimed to develop a dried CSF spot protocol and to evaluate its diagnostic performance using the World Health Organisation recommended anti-JEV IgM antibody capture enzyme-linked immunosorbent assay (JEV MAC-ELISA). Methodology and Principal Findings: Sample volumes, spotting techniques and filter paper type were evaluated using a CSF-substitute of anti-JEV IgM positive serum diluted in Phosphate Buffer Solution (PBS) to end-limits of detection by JEV MAC-ELISA. A conventional protocol, involving eluting one paper punch in 200μl PBS, did not detect the end-dilution, nor did multiple punches utilising diverse spotting techniques. However, pre-cut filter paper enabled saturation with five times the volume of CSF-substitute, sufficiently improving sensitivity to detect the end-dilution. The diagnostic accuracy of this optimised protocol was compared with routine, neat CSF in a pilot, retrospective study of JEV MAC-ELISA on consecutive CSF samples, collected 2009–15, from three Lao hospitals. In comparison to neat CSF, 132 CSF samples stored as dried CSF spots for one month at 25–30°C showed 81.6% (65.7–92.3 95%CI) positive agreement, 96.8% (91.0–99.3 95%CI) negative agreement, with a kappa coefficient of 0.81 (0.70–0.92 95%CI). Conclusions/Significance: The novel design of pre-cut filter paper saturated with CSF could provide a useful tool for JEV diagnostics in settings with limited laboratory access. It has the potential to improve national JEV surveillance and inform vaccination policies. The saturation of filter paper has potential use in the wider context of pathogen detection, including dried spots for detecting other analytes in CSF, and other body fluids. [ABSTRACT FROM AUTHOR]

A pilot-scale aerated lagoon was used for the aerobic treatment of pulp and paper mill effluent from September 1 to December 1, 2014. The aerated lagoon was installed at the chemistry laboratory in the Chemical Engineering Department at the Durango Institute of Technology and was fed with real pulp and paper mill effluent. The experimental work was run under various operating conditions. The operating parameters (total and volatile suspended solids (VSS) and dissolved oxygen concentration (DO)) and environmental variables (temperature, pH, COD, and BOD5 of influent water) were monitored daily. In all the experiments conducted, the aerated lagoon generated an effluent of optimal quality complying with the requirements of SEMARNAT (2003) and CONAGUA (2003). A model that explains the behavior of the system under realistic operating conditions was obtained. The model indicated an optimal DO of approximately 4 mg/L for concentrations up to 1000 mg/L, showing variations in concentrations above this value. This data indicate that the flexibility of the bacterial formulation and its ability to adapt to environmental changes play an important role in the stability of an aerated lagoon. [ABSTRACT FROM AUTHOR]

Early industrialization and the development of cheap production processes for paper have led to an exponential accumulation of paper-based documents during the last two centuries. Archives and libraries harbor vast amounts of ancient and modern documents and have to undertake extensive endeavors to protect them from abiotic and biotic deterioration. While services for mechanical preservation such as ex post de-acidification of historic documents are already commercially available, the possibilities for long-term protection of paper-based documents against fungal attack (apart from temperature and humidity control) are very limited. Novel processes for mechanical enhancement of damaged cellulosic documents use Ionic Liquids (IL) as essential process components. With some of these ILs having azole-functionalities similar to well-known fungicides such as Clotrimazole, the possibility of antifungal activities of these ILs was proposed but has not yet been experimentally confirmed. We evaluated the potency of four ILs with potential application in paper restoration for suppression of fungal growth on five relevant paper-infesting molds. The results revealed a general antifungal activity of all ILs, which increased with the size of the non-polar group. Physiological experiments and ultimate elemental analysis allowed to determine the minimal inhibitory concentration of each IL as well as the residual IL concentration in process-treated paper. These results provide valuable guidelines for IL-applications in paper restoration processes with antifungal activity as an added benefit. With azoles remaining in the paper after the process, simultaneous repair and biotic protection in treated documents could be facilitated. [ABSTRACT FROM AUTHOR]

Rupert Jethro Best (1903–91), working alone at the Waite Agricultural Research Institute in Adelaide between 1934 and 1937, was among the first to purify tobacco mosaic virus (TMV) and to propose that it was a complex macromolecule containing protein and another reactive group that was responsible for infectivity of the virus. However, his research was completely overshadowed by that of Wendell Stanley and the duo of Frederick Bawden and Norman (aka Bill) Pirie, working in the United States of America and Great Britain, respectively, to the point where Best is not even mentioned in modern histories of TMV. Many factors have contributed to this lack of recognition for Best. Professor James Prescott, a soil scientist and Best's supervisor at the Waite Institute, failed to appreciate the significance of his research, leading to critical delays in publication that prevented him from claiming precedence for purifying TMV. When Best's research was eventually published, it was in Australian journals that were not broadly distributed, resulting in minimal international exposure for his research. The plant virology community within which he worked in Australia was very small and entirely focused on plant disease control, and not concerned with fundamental questions about the composition of viruses. Communication with similarly interested scientists in the Northern Hemisphere was hindered by the great distances involved. In this paper, pioneering research done by Best on TMV is reviewed, and placed in context with that undertaken by Stanley and by Bawden and Pirie, who are best remembered for purifying TMV and characterising its physicochemical properties. Rupert Jethro Best, working alone in Adelaide at the Waite Agricultural Research Institute, was among the first to purify tobacco mosaic virus and to provide evidence that it was a heterogeneous macromolecule, composed mainly of protein but also small prosthetic groups with the properties of a weak acid, wherein lay the activity of the virus. This paper describes the contributions of Rupert Best to early theories on the material nature and mode of reproduction of viruses. Photographer unknown, State Library of South Australia. [ABSTRACT FROM AUTHOR]

Biosensors have emerged as a valuable tool with high specificity and sensitivity for fast and reliable detection of hazardous substances in drinking water. Numerous substances have been addressed using synthetic biology approaches. However, many proposed biosensors are based on living, genetically modified organisms and are therefore limited in shelf life, usability and biosafety. We addressed these issues by the construction of an extensible, cell-free biosensor. Storage is possible through freeze drying on paper. Following the addition of an aqueous sample, a highly efficient cell-free protein synthesis (CFPS) reaction is initiated. Specific allosteric transcription factors modulate the expression of ‘superfolder’ green fluorescent protein (sfGFP) depending on the presence of the substance of interest. The resulting fluorescence intensities are analyzed with a conventional smartphone accompanied by simple and cheap light filters. An ordinary differential equitation (ODE) model of the biosensors was developed, which enabled prediction and optimization of performance. With an optimized cell-free biosensor based on the Shigella flexneri MerR transcriptional activator, detection of 6 μg/L Hg(II) ions in water was achieved. Furthermore, a completely new biosensor for the detection of gamma-hydroxybutyrate (GHB), a substance used as date-rape drug, was established by employing the naturally occurring transcriptional repressor BlcR from Agrobacterium tumefaciens. [ABSTRACT FROM AUTHOR]

Background: The lack of information regarding the burden of acute bacterial meningitis in Latin America leads to a reduction in the estimated incidence rates of the disease, and impairs public health decisions on the use and follow-up of preventive interventions, particularly, the evaluation of existing vaccination policies. The use of the real-time PCR in diagnostic routine procedures has resulted in a substantial increase in confirmed bacterial meningitis cases. However, in resource-poor countries, these assays are only available in reference laboratories. Sample transportation to these laboratories is a critical constraint, as it requires specialized, high cost courier services. To overcome this barrier we evaluated the use of FTATM Elute filter paper cards for the conservation and processing of samples under normal environmental conditions, as they would be when transported from remote and under-equipped healthcare facilities to the reference centers. A total of 401 samples received in 2015 as part of Sao Paulo’s national surveillance for routine diagnosis were selected for this study. Methods: The sensitivity and specificity of real-time PCR were evaluated using fresh serum and cerebrospinal fluid (CSF) samples processed using our laboratory’s standard DNA extraction, and processing the same samples after being dried and stored on FTATM card, and DNA extracted following the manufacturer’s instructions. Results: The sensitivities for detection of Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae from CSF dried and stored on FTATM cards were 98%, 92%, and 100%, respectively, and with serum samples were 73%, 88%, and 100%, respectively. When compared to our laboratory’s standard methodology, results showed high concordance, with Kappa index ranges of 0.9877–1.00 for CSF, and 0.8004–1.00 for serum samples. Conclusion: The use of FTATM cards for CSF and serum conservation and transport represents a rapid, reliable, and cost-effective alternative that will allow obtaining valuable epidemiological information that would otherwise be lost. [ABSTRACT FROM AUTHOR]

Paper mills processing recycled paper suffer from biofouling causing problems both in the mill and final product. The total bacterial community composition and identification of specific taxa in the process water and biofilms at the stock preparation and paper machine areas in a mill with recycled paper pulp was described by using a DNA-based approach. Process water in a similar mill was also analyzed to investigate if general trends can be found between mills and over time. Bacterial community profiles, analyzed by terminal-restriction fragment length polymorphism (T-RFLP), in process water showed that the dominant peaks in the profiles were similar between the two mills, although the overall composition was unique for each mill. When comparing process water and biofilm at different locations within one of the mills, we observed a separation according to location and sample type, with the biofilm from the paper machine being most different. 16S rRNA gene clone libraries were generated and 404 clones were screened by RFLP analysis. Grouping of RFLP patterns confirmed that the biofilm from the paper machine was most different. A total of 99 clones representing all RFLP patterns were analyzed, resulting in sequences recovered from nine bacterial phyla, including two candidate phyla. Bacteroidetes represented 45% and Actinobacteria 23% of all the clones. Sequences with similarity to organisms implicated in biofouling, like Chryseobacterium spp. and Brevundimonas spp., were recovered from all samples even though the mill had no process problems during sampling, suggesting that they are part of the natural paper mill community. Moreover, many sequences showed little homology to as yet uncultivated bacteria implying that paper mills are interesting for isolation of new organisms, as well as for bioprospecting. [ABSTRACT FROM AUTHOR]

Here we describe an ultra-low-cost origami-based approach for large-scale manufacturing of microscopes, specifically demonstrating brightfield, darkfield, and fluorescence microscopes. Merging principles of optical design with origami enables high-volume fabrication of microscopes from 2D media. Flexure mechanisms created via folding enable a flat compact design. Structural loops in folded paper provide kinematic constraints as a means for passive self-alignment. This light, rugged instrument can survive harsh field conditions while providing a diversity of imaging capabilities, thus serving wide-ranging applications for cost-effective, portable microscopes in science and education. [ABSTRACT FROM AUTHOR]

Mixed microbial culture from paper mill treatment system was enriched on polyvinyl alcohol (PVA) medium and its PVA biodegradation capacity was investigated as a function of change in the initial pH values and PVA concentrations. The optimum pH value at 0.75 gl-1 initial PVA concentration was determined to be 8. PVA biodegradation by mixed microbial culture was investigated at the range of 0.68 - 15.5 gl-1 initial PVA concentrations. The mixed microbial culture was found to degrade within 5 days 98.6-88.5% of the initial PVA levels which ranged from 0.68 to 1.14 gl-1. The mixed microbial culture was found to remove more than 90% of the initial PVA concentrations, within the range of 3.13 to 6.64 g1-1 in 16-25 days of incubation at 35 °C. [ABSTRACT FROM AUTHOR]

Highlights: [•] Microbial bioanodes were formed in raw pulp and paper mill effluent. [•] In well-controlled conditions 4A/m2 were reached at −0.3V/ECS. [•] A theoretical model determined the contribution of the bioanode to the COD removal. [•] Electrochemical COD removal was proportional to HRT. [•] Electrochemical COD removal obeyed a Michaelis–Menten law with the COD outlet. [ABSTRACT FROM AUTHOR]

Pyocyanin is a toxin produced by Pseudomonas aeruginosa. Here we describe a novel paper-based electrochemical sensor for pyocyanin detection, manufactured with a simple and inexpensive approach based on electrode printing on paper. The resulting sensors constitute an effective electrochemical method to quantify pyocyanin in bacterial cultures without the conventional time consuming pretreatment of the samples. The electrochemical properties of the paper-based sensors were evaluated by ferri/ferrocyanide as a redox mediator, and showed reliable sensing performance. The paper-based sensors readily allow for the determination of pyocyanin in bacterial cultures with high reproducibility, achieving a limit of detection of 95 nM and a sensitivity of 4.30 μA/μM in standard culture media. Compared to the similar commercial ceramic based sensors, it is a 2.3-fold enhanced performance. The simple in-house fabrication of sensors for pyocyanin quantification allows researchers to understand in vitro adaptation of P. aeruginosa infections via rapid screenings of bacterial cultures that otherwise are expensive and time-consuming. [ABSTRACT FROM AUTHOR]

This study sought to investigate the significance of raw materials (starch-based glues, raw material papers) at different microbiologically critical stages in the manufacturing process of refined paper products. The study examined the occurrence of microorganisms in the process and in end-product samples. Microbiological surveys verified that the production and use of pasteurized starch-based glue was the most important factor threatening the process hygiene and product safety. Subsequently, the production and use of starch-based glue was changed, and a follow-up programme targeting the microbiological quality of glue was developed as part of a hygiene and safety management system. A total of 33 spore-forming bacterial and 15 enterobacterial isolates were ribotyped, and 22 and 10 different ribogroups (ribotypes), respectively, were generated. These isolates from starch-based glue, raw material paper and end products were atypical and, thus, in many cases physiological, chemotaxonomic (FAME) and molecular (partial 16S rDNA) results did not correspond. The most common spore-forming bacteria (55% of the isolates) were Paenibacillus sp. and within this genus several new species were also proposed. The most common enterobacteria (87%) were Enterobacter cloacae and Citrobacter freundii belonging to bacteria in hazard group 2, or species closely related to them. It was demonstrated that the same spore-forming bacteria (ribotypes) were present in both the glue samples and the end products (45% of isolates). All RiboPrint® patterns were saved at the VTT identification library for future use. [ABSTRACT FROM AUTHOR]

An incubation study was conducted under laboratory conditions to compare the effects of soil amendment of combined paper mill sludge (PS) and decomposed cow manure (DCM) on selected microbial indicators. A lateritic soil (Typic Haplustalf) was amended with 0 (control), 20 or 80tha−1 (wet weight) of PS or DCM. The amended soils were then adjusted to 60% water holding capacity (WHC) or submerged conditions, and incubated at 27°C in dark for up to 120days (d). The microbial biomass C (MBC), the basal soil respiration and the enzyme activities of the β-glucosidase, acid phosphatase and sulphatase were analyzed at day 15, 30, 45, 60 and 120. Compared to the unamended soil (control), the MBC, the basal soil respiration and the enzyme activities increased with the rate of PS and DCM. At similar rate, the DCM treatment increased significantly the MBC, the soil respiration and the enzyme activities compared to the PS treatment. Also, the water regimes affected the microbial activities. At 60% WHC, the MBC and soil respiration increased during the first 30d and decreased thereafter. The enzyme activities showed similar trends, where they increased for the first 60d, and decreased thereafter. In contrast, under submerged condition, the MBC and enzymes activities declined during 120d, whereas the soil respiration increased. Compared to the control, the used of PS and DCM had no negative impact of the soil microbial parameters, even at the highest application rate. Long-term field experiments are required to confirm these laboratory results. [Copyright &y& Elsevier]

Aims: A public beach was frequently cited for health advisories because of high Escherichia coli levels, the source suspected to be a paper mill located upstream. This investigation sought to confirm whether or not the paper mill was the pollution source, and to characterize the risk to recreational bathers imposed by the source. Methods and Results: Quantification of E. coli in river water collected at incremental distances showed that paper mill effluent caused elevated E. coli levels in beach samples. Samples collected throughout the mill were variably positive for heterotrophic bacteria, total coliforms and E. coli, but negative for pathogenic E. coli O157 and Salmonella. Escherichia coli O157 or Salmonella spiked into mill samples (4·2 log10 or 5·6 log10 CFU per 100 ml, respectively) fell below detection levels within 14–24 h in raw (unaltered) samples, while in heat-sterilized replicates, the counts remained at initial levels or increased over 36 h. Conclusions: Pathogenic E. coli O157 and Salmonella were not isolated from paper mill samples. The absence of native bacteria allowed the survival of pathogens, while their presence accelerated pathogen decline. Significance and Impact of the Study: The co-existence of paper mill and swimming beach may be reasonable for now in spite of the limitations of an E. coli-based assay for beach water. [ABSTRACT FROM AUTHOR]

The main goal of this work was to reinforce softwood pulp (SP) with bacterial cellulose (BC) to generate a sustainable biocomposite. BC is a nanocellulose, which was anticipated to increase interfacial adhesion between the cellulosic fibers and BC. The organism used was Gluconacetobacter xylinus , which was incubated in a static Hestrin-Schramm culture at 28 °C for 14 days. The specimens of BC, SP and the reinforced SP with BC were characterized using X-ray diffraction (XRD), FT-IR, FESEM, and physico-mechanical testing. The crystallinity index was found to be 83 and 54% for BC and SP, respectively. FT-IR spectra showed that the composition of BC was fully different from that of SP fibers. Based on FESEM images, one can conclude that BC and softwood fibers do form a good combination with a nonporous structure. BC fibers fill in among the softwood fibers in the sheet. The physical and mechanical properties showed that as the dosage of BC increased, the properties of tensile index, tear index, and burst index greatly improved, while the porosity and the elongation decreased. The reason for the improved mechanical properties can be attributed to the increase of interfibrillar bonding which reduced porosity. This would be due to the high aspect ratio of BC that is capable of connecting between the cellulosic fibers and BC nanofibers, enhancing a large contact surface and therefore producing excellent coherence. This study suggests that BC could be a promising material for reinforcing composites at low loading. [ABSTRACT FROM AUTHOR]

Culture conditions for the production of cellulase-free endo-β-1,4-xylanase by an alkalophilic strain of Bacillus subtilis SD8 (BsSD8-xylanase) isolated from paper mill effluent were optimized using 2 factorial design and response surface methodology. Statistical analysis of results showed that the linear and quadratic terms and interaction of 4 variables (temperature, pH, inoculum size and xylan concentration) had significant effects. The optimal conditions for production of the enzyme were: 37.5°C, initial pH of 8.5, inoculum size of 8.5% and xylan concentration of 2%. The predicted and verified BsSD8-xylanase activities under optimal conditions were 8.18 IU/mL. Analysis revealed that the enzyme gene consists of an ORF of 642 bp encoding a protein of 213 amino acids with a molecular mass of 23.5 kDa and pI of 9.67. Secondary and tertiary structure prediction using SOPMA and SWISS model showed a maximum homology of 95.14% with β1,4-xylanase (PDB Id.: 1BVV) of Bacillus circulans obtained from protein data bank. The results of the study indicate that this enzyme presents a potentially effective xylan-biodegrading tool that could be useful for pulp and paper biobleaching. [ABSTRACT FROM AUTHOR]

As more HIV-infected people gain access to antiretroviral therapy (ART), monitoring HIV drug resistance (HIVDR) becomes essential to combat both acquired and transmitted HIVDR. Studies have demonstrated dried blood spots (DBS) are a suitable alternative in HIVDR monitoring using DBS collected on Whatman 903 (W-903). In this study, we sought to evaluate two other commercially available filter papers, Ahlstrom 226 (A-226) and Munktell TFN (M-TFN), for HIVDR genotyping following ambient temperature storage. DBS were prepared from remnant blood specimens collected from 334 ART patients and stored at ambient temperature for a median time of 30 days. HIV-1 viral load was determined using NucliSENS EasyQ® HIV-1 v2.0 RUO test kits prior to genotyping of the protease and reverse transcriptase regions of the HIV-1 pol gene using an in-house assay. Among the DBS tested, 26 specimens had a viral load ≥1000 copies/mL in all three types of filter paper and were included in the genotyping analysis. Genotyping efficiencies were similar between DBS collected on W-903 (92.3%), A-226 (88.5%), and M-TFN (92.3%) filter papers (P = 1.00). We identified 50 DR-associated mutations in DBS collected on W-903, 33 in DBS collected on A-226, and 48 in DBS collected on M-TFN, resulting in mutation detection sensitivities of 66.0% for A-226 and 88.0% for M-TFN when compared to W-903. Our data indicate that differences among filter papers may exist at this storage condition and warrant further studies evaluating filter paper type for HIVDR monitoring. [ABSTRACT FROM AUTHOR]

Objective: Robust scientific and clinical evidence of how to appropriately manage denture plaque is lacking. This two-part study (i) developed an in vitro model of denture plaque removal, and (ii) assessed effectiveness of these approaches in a randomised clinical trial. Method: (i) a complex denture plaque model was developed using the dominant microbial genera from a recent microbiome analyses. Biofilms formed on polymethylmethacrylate were brushed daily with a wet toothbrush, then either treated daily for 5 days or only on Days 1 and 5 with Polident® denture cleanser tablets (3 min soaking). Quantitative and qualitative microbiological assessments were performed. (ii), an examiner-blind, randomised, crossover study of complete maxillary denture wearers was performed (n = 19). Either once-daily for 7 days or on Day 7 only, participants soaked dentures for 15 min using Corega® denture cleansing tables, then brushed. Denture plaque microbiological assessment used sterilized filter paper discs. Results: The in vitro model showed daily cleaning with denture cleanser plus brushing significantly reduced microbial numbers compared to intermittent denture cleaning with daily brushing (p < 0.001). The clinical component of the study showed a statistically significant reduction in denture plaque microbial numbers in favour of daily versus weekly treatment (aerobic bacteria p = 0.0144). Both in vitro and in vivo studies showed that denture plaque biofilm composition were affected by different treatment arms. Conclusions: This study demonstrated that daily denture cleansing regimens are superior to intermittent denture cleansing, and that cleansing regimens can induce denture plaque compositional changes. Clinicaltrials.gov registration: NCT02780661. [ABSTRACT FROM AUTHOR]

This article is an editorial for a thematic issue on Polar and Alpine Microbiology in the journal FEMS Microbiology Ecology. The issue focuses on the microbial ecology of cold habitats and the importance of understanding the biodiversity and functional roles of microorganisms in these environments. The issue includes 30 peer-reviewed papers, most of which were presented at the 9th International Conference on Polar and Alpine Microbiology (PAM22). The papers cover a range of topics, including microbial communities, adaptation, carbon and nitrogen turnover, and plant-microbe interactions, with a particular emphasis on Arctic, mountain, and Antarctic regions. The issue is dedicated to the late researcher S. Craig Cary, who made significant contributions to the study of microbial life in extreme environments. [Extracted from the article]

Abstract: Biofouling causes important economic losses in the paper industry. To prevent or mitigate the effects of biofilms it is necessary to implement microbiological control programs that require the evaluation of biofilm growth kinetics taking into account the viability of microorganisms. The monitoring techniques needed for this purpose must be rapid to minimize both costs and the use of chemicals. This paper presents a study on the growth kinetics of two bacterial strains known for their capacity to produce biofilms in paper mills. After the validation of flow cytometry as a technique for microbial growth monitoring, two segregated kinetic models integrating cell physiological state data were implemented. The models developed can be used to devise microbial control programs. [Copyright &y& Elsevier]

During the process of papermaking by pulp and paper plants, a thick and viscous deposits, termed slime, is quickly formed around the paper machines, which can affect the papermaking process. In this study, we explored the composition of the bacterial biota in slime that developed on shower pipes from 2 machines at a Canadian paper mill. Firstly, the composition was assessed for 12 months by DNA profiling with polymerase chain reaction coupled with denaturing gradient gel electrophoresis. Except for short periods (2-3 months), clustered analyses showed that the bacterial composition of the slime varied substantially over the year, with less than 50% similarity between the denaturing gradient gel electrophoresis profiles. Secondly, the screening of 16S rRNA gene libraries derived from 2 slime samples showed that the most abundant bacteria were related to 6 lineages, including Chloroflexi, candidate division OP10, Clostridiales, Bacillales, Burkholderiales, and the genus Deinococcus. Finally, the proportion of 8 bacterial lineages, such as Deinococcus sp., Meiothermus sp., and Chloroflexi, was determined by the Catalyzed Reporter Deposition - Fluorescence In Situ Hybridization in 2 slime samples. The results showed a high proportion of Chloroflexi, Tepidimonas spp., and Schlegelella spp. in the slime samples. Lors du processus de fabrication industrielle du papier, un dépôt épais et visqueux se forme rapidement autour des machines à papier, ce qui peut affecter le processus de fabrication. Dans cette étude, nous avons exploré la composition bactérien ne du dépôt qui s'est développée sur des tuyaux des douches de 2 machines d'une usine à papier au Canada. La composition a d'abord été évaluée pendant 12 mois par la détermination du profil d'ADN par une réaction en chaîne par polymérase couplée à une électrophorèse sur gel en gradient dénaturant. À part de courtes périodes (2-3 mois), les analyses ont montré que la composition bactérienne du dépôt variait substantiellement au cours de l'année, avec moins de 50 % de similarité entre les profils en l'électrophorèse sur gel en gradient dénaturant. Deuxièmement, le criblage de banques géniques d'ARN ribosomique 16S dérivées de 2 échantillons de dépôt a ensuite montré que les bactéries les plus abondantes étaient apparentées à 6 lignées, notamment les Chloroflexi, la division candidate OP10, les Clostridiales, les Bacillales, les Burkholderiales, et le genre Deinococcus. Finalement, la proportion de 8 lignées bactériens comme Deinococcus sp., Meiothermus sp. et Chloroflexi a été déterminée par « Catalyzed Reporter Deposition - Fluorescence In Situ Hybridization » dans 2 échantillons de dépôt. Les résultats ont montré une forte proportion de Chloroflexi, Tepidimonas spp. et Schlegelella spp. dans les échantillons. [ABSTRACT FROM AUTHOR]

Paper, like all other cultural heritage materials, degrades over time, but conservation slows down the rate of its deterioration. There is a long history of cooperation between microbiologists and conservators of libraries and archival materials, but current approaches addressing paper deterioration need urgent reassessment to take full advantage of modern microbiological methodologies. The present article discusses what we believe are the current priority research areas in assessing microbial risk to paper heritage, and reports studies on a 13th century Italian manuscript and on Leonardo da Vinci''s Atlantic Codex which illustrate the problems and challenges encountered when dealing with microbial investigations of paper artworks. The potential of using a more advanced microbiological approach is highlighted. [Copyright &y& Elsevier]

In this study a rapid at-line ATP (adenosine triphosphate) analysis is applied in papermaking. This ATP analysis takes less than a minute, and the information can be utilized instantly to adapt the biocide program. The study shows the effect of different biocide strategies at paper mills. Comparison is made between oxidative and reductive biocides on the one hand, and on the other hand between continuous vs. batch additions of biocide. Continuous biocide addition keeps the microbial activity at a constant level. However, a long production period without a boil-out might result in accumulation of resistant bacteria, which cannot be eliminated without changing the biocide strategy. Batch addition of biocide creates a high temporary concentration of biocide in the process. This causes lower temporary microbial activity in the process, but between the doses the microbial activity may rise to an intolerable level. Batch addition causes chemical variation to the wet end of a paper machine more easily than continuous addition. This can affect the performance of papermaking chemicals and cause problems with retention, fixing, etc. Both biocide addition strategies can be used if they are monitored and optimized properly. Rapid ATP analysis is a suitable tool for both purposes. [ABSTRACT FROM AUTHOR]

To detect antibiotic-resistant bacteria in areas remote from microbiology laboratories, we designed portable culture devices performing an analogue of the Kirby–Bauer disk diffusion test inside patterned papers embedded in tape. We quantified the antibiotic susceptibility of several strains of Escherichia coli and Salmonella typhimurium by measuring blue-colored zones of inhibited growth. [ABSTRACT FROM AUTHOR]

Virtual Reality (VR) laboratories are a new pedagogical approach to support psychomotor skills development in undergraduate programmes to achieve practical competency. VR laboratories are successfully used to carry out virtual experiments in science courses and for clinical skills training in professional courses. This paper describes the development and evaluation of a VR-based microbiology laboratory on Head-Mounted Display (HMD) for undergraduate students. Student and faculty perceptions and expectations were collected to incorporate into the laboratory design. An interactive 3-dimensional VR laboratory with a 360° view was developed simulating our physical laboratory setup. The laboratory environment was created using Unity with the (created) necessary assets and 3D models. The virtual laboratory was designed to replicate the physical laboratory environment as suggested by the students and faculty. In this VR laboratory, six microbiology experiments on Gram staining, bacterial streaking, bacterial motility, catalase test, oxidase test and biochemical tests were placed on the virtual platform. First-year biomedical science students were recruited to evaluate the VR laboratory. Students' perception of the virtual laboratory was positive and encouraging. About 70% of the students expressed they felt safe using the VR laboratory and that it was engaging. They felt that the VR laboratory provided an immersive learning experience. They appreciated that they could repeat each experiment multiple times without worrying about mistakes or mishaps. They could personalise their learning by concentrating on the specific experiments. Our in-house VR-based microbiology laboratory was later extended to other health professions programmes teaching microbiology. [ABSTRACT FROM AUTHOR]

This paper investigates the correlation of ResearchGate among the faculties of sciences in the central universities of North-East India using Altmetrics approaches. As more innovation is seen and the discipline is in its early stages, the Department of Biotechnology and Microbiology is the primary study area. The study focuses primarily on faculty activities on the ResearchGate platform, which include frequency of publications, citations, research interest, number of followers and followings, and various publication formats. It has also sparked interest in determining the relationships between different ResearchGate metrics. According to the study, most faculties have good citation scores and an average number of publications. The survey analysis reveals a lack of awareness, concentration, and dedication to the development of the disciplines. The result of the investigation shall serve as a pathway for various future goals for selfimprovement. [ABSTRACT FROM AUTHOR]

The human oral cavity is normally colonized by microorganisms including bacteria, fungi, archaea, viruses and protozoa. The aim of this study was to determine the frequency of Candida spp., in de oral cavity in a group of medical students from the north of Mexico. Oral sample were obtained from 240 healthy students. The specimens were analyzed by traditional microbiology cultures and DNA sequencing. Candida spp., grew in Sabouraud dextrose agar from 57 samples and subsequently were isolated and phenotyped. The definitive identification to the species level was done by sequence analysis. The yeasts were identified as follow: 28 Clavispora lusitaniae, 20 Candida albicans, 5 Pichia kudriavzevii and 4 Candida parapsilosis. Our findings revealed that 23.75% of the healthy population has a potential pathogen in their mouth. Surprisingly, C. albicans is not the predominant yeast; instead other non-Candida species are the colonizers of the oral cavity as normal microbiota. C. lusitaniae is considered an emerging opportunistic pathogen in immunosuppressive patients. This paper pretends to highlight the presence of this yeast in the oral cavity in immunocompetent young adults. [ABSTRACT FROM AUTHOR]

Multiple independent approaches were applied for monitoring the abundance and identity of sulfate-reducing bacteria (SRB) in pulp of a paper-recycling plant suffering from excessive sulfide emission. The methods applied included most-probable-number (MPN) enumeration of cultivable SRB, rate measurements, FISH and PCR-based retrieval of the functional marker genes dsrA and B (encoding the two major subunits of dissimilatory bisulfite reductase) and 16S rRNA genes. The SRB community was composed of phylogenetically highly different lineages all of low abundance relative to the total microbial community in the pulp, which hampered the applicability of FISH. It was also demonstrated that dsrA- or B-targeted PCR primers commonly used for denaturing gradient gel electrophoresis and real-time PCR analyses were biased. However, using a novel approach combining MPN-PCR and terminal restriction fragment length polymorphism analysis of dsrAB amplicons generated from serially diluted DNA extracts allowed the enumeration and identification of the quantitatively most important members of the SRB community. For fast quantification of SRB in the pulp, the dsrAB-MPN-PCR assay and sulfate reduction rate measurements were found to be most suitable. [ABSTRACT FROM AUTHOR]

This study investigated the effects of cyanobacteria from pulp-and-paper waste-treatment systems on biological toxicity removal and biodegradation of certain wastewater contaminants. In field and batch studies, using the Microtox® assay, cyanobacterial biomass and final wastewater toxicity were significantly correlated. In softwood-based wastewater, a decrease in toxicity was negatively correlated with cyanobacterial biomass, but the correlation was positive in hardwood-based wastewater. In the softwood-based wastewater, toxicity remained higher in the light than it was in the dark, whereas in hardwood-based wastewater, toxicity was lower in the light than it was in the dark. All of these results were light-dependent, suggesting that the photosynthetic growth of cyanobacteria is required to induce significant effects. When grown in mixed cultures with bacterial degraders, cyanobacteria from pulp-and-paper waste-treatment systems generally impeded the biodegradation of the wastewater contaminants phenol and dichloroacetate (DCA). However, there was one case where the cyanobacterium Phormidium insigne improved the bacterial degradation of DCA. Doubling inorganic nutrient concentrations did not improve phenol or DCA biodegradation in the majority of cases, indicating that nutrient competition is not a major factor. These data suggest that cyanobacteria play an important role during the biological treatment of contaminants, and, hence, toxicity removal in pulp-and-paper waste-treatment systems.Key words: cyanobacteria, heterotrophic bacteria, biodegradation, pulp and paper waste-treatment, wastewater toxicity. [ABSTRACT FROM AUTHOR]

Abstract: Vermicomposts have been shown to promote the germination, growth, and yields of plants. This paper aims to demonstrate the effects of vermicomposts produced from three types of wastes on growth and flowering of petunias which are an important U.S. flowering crop. Vermicomposts, produced commercially from cattle manure, food wastes and paper wastes, were substituted at a range of different concentrations into with a soilless commercial bedding plant container medium, Metro-Mix 360 (MM360), to evaluate their effects on the growth and flowering of petunias (Petunia sp.) in the greenhouse. Seeds of petunia (var. Dreams Neon Rose F1) were sown into 100, 90, 80, 70, 60, 50, 40, 30, 20 or 10% MM360 substituted with 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 or 100% cattle manure, food waste or paper waste vermicompost. Each type of vermicompost constituted a separate sub-experiment. All plants were watered three times weekly with 200ppm Peter''s nutrient solution, containing all nutrients required, from sowing up to 79 days. Substitutions with all of the vermicomposts into MM360 increased germination significantly on almost all sampling dates. Shoot dry weights increased significantly after substituting MM360 with 10–60% cattle manure vermicompost, and 10–100% of both food waste and paper waste vermicomposts. Numbers of flowers increased significantly after MM360 substitutions with 20–40% of both cattle manure and food waste vermicomposts, and by only 40% of paper waste vermicompost. There were no positive correlations between the increases in numbers of flowers, and the amounts of mineral-N and microbial biomass-N in the potting mixtures, or the concentrations of N in the shoot tissues of petunias. Factors such as improvement of the physical structure of the potting medium, increases in populations of beneficial microorganisms, and most probably, the availability of plant growth-influencing-substances such as hormones and humates produced by microorganisms during vermicomposting, probably contributed to the increased petunia germination, growth and flowering. [Copyright &y& Elsevier]

The cellulose-hydrolyzing strains, Sphingomonas paucimobilis MK1 and Bacillus circulans MK2, were separated from soil and were grown together in a single culture plate. Growth B. circulans MK2 in liquid culture required symbiosis with S. paucimobilis MK1. Biological pretreatment with the combined strain suspension after the liquid culture improved enzymatic hydrolysis of office paper from municipal wastes. Sugar recovery by S. paucimobilis MK1 (51%) was 1.4 times higher than that of the untreated sample (30%) and in the strain combination with B. circulans MK2, recovery was further improved by 2.5 times (75%). The sugar recovery in maximum condition was enhanced up to 94% for office paper. Furthermore, biological pretreatment effects were confirmed for more than 1 day less time. In X-ray diffraction patterns for the crystallinity of cellulose in office paper changed after biological pretreatment, the crystallinity was increased in comparison to that in untreated paper. The mechanism of biological pretreatment effect was explained by the fact that the strain acted as an endoglucanase, which hydrolyzes amorphous areas randomly. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge of the microbiology of dinitrogen (N2)-fixing bacteria in compost rich in de-inking paper sludge (DPS) is limited. Dinitrogen (N2)-fixing bacteria from DPS composts were isolated and studied for their N2-fixing activity in vitro and in vivo. Two Gram-negative N2-fixing isolates were identified as Pseudomonas. At 20°C, both isolates revealed that N2-fixing activity was higher than that of three arctic Pseudomonas strains. Their N2-fixing activity was found to occur between 18 and 25°C, a pattern that was similar to the reference isolate Azotobacter ATCC 7486. Composts successfully showed N2-fixing activity after carbohydrate amendments both with and without inoculation of a N2-fixing isolate. These results suggest that DPS composts support N2-fixing bacteria and that N2-fixing activity is dependent on a usable carbohydrate source. [Copyright &y& Elsevier]

The aim of this study was to develop a PCR-based rapid method to detect Bacillus cereus group cells from paper and cardboard. Primers targeting the 16S rDNA and real-time PCR with SYBR green I detection were used in order to be able to also quantify the target. Both autoclaved cardboard samples spiked with B. cereus vegetative cells or spores and naturally contaminated paper and cardboard samples were studied. Results were compared with culturing verified by commercial (API) tests. Several different methods were tested for DNA isolation from the paper and cardboard samples. Two commercial kits intended for soils, the UltraClean soil DNA kit and the FastDNA spin kit for soil, gave the most reproducible results. In spiked samples, the average yield was 50% of added vegetative cells, but spore yield was only about 10%. PCR results from adding vegetative cells correlated with added colony-forming unit (cfu) values (r=0.93, P <0.001) in the range 100–10,000 cfu g-1. Three out of nine studied paper and cardboard samples contained B. cereus group bacteria, based both on culturing and real-time PCR. The numbers were 102–103 bacteria g-1; and PCR gave somewhat higher results than culturing. Thus, real-time PCR can be used as a rapid semi-quantitative method to screen paper and cardboard samples for contamination with B. cereus group bacteria. [ABSTRACT FROM AUTHOR]

Composting is an alternative method to dispose of de-inking paper sludge (DPS). Today, few studies have investigated the water-soluble carbon (WSC) substances as indicators of the decomposition process and the microbial changes taking place during the composting of DPS. Accordingly, the goal is to study their dynamics during the composting of DPS at three nitrogen levels, 0.6%, 0.7% or 0.9% total N, using mechanical turning. The changes in WSC substances, microbial biomass carbon (MBC) and, total and DPS microbial populations were monitored during 24 weeks. Also, microorganisms were identified and tested for the production of selected enzymes. Regardless of N treatments, the dynamic of WSC substances indicated that cellulose and hemicellulose fractions of DPS fibers were mainly biodegraded during the first 8 weeks while the more resistant carbon (C) fractions were biodegraded thereafter. MBC also evolved regardless of N treatments but was correlated to WSC substances. Its high values decline mostly after 12 weeks indicating the exhaustion of this source of C energy for microbial growth and the stabilisation of DPS organic matter. The dynamic and identified microorganisms were comparable to those observed in other composting processes. However, the results pointed out that those mostly implicated in the hydrolysis of DPS fibers were the thermophilic actinomycetes and fungi and, by comparison to the 0.6% or 0.7% N treatment, they decreased in presence of the 0.9% N treatment. Most microorganisms were hemicellulolytic bacteria, while actinomycetes and fungi were capable of degrading a wide variety of substrates. Overall, dynamics of WSC substances and microbial populations indicated that during composting, DPS decomposition obey a two phase decay while, contrary to the lowest N treatment, the 0.9% N treatment has slowed down this process by harming the important microbial populations implicated in the degradation of DPS fibers. [Copyright &y& Elsevier]

Background: The development in the deinking process has made recycled fiber a major part of the raw material for pulp and paper industry. Enzymes have revolutionized the deinking process obtaining brightness levels surpassing conventional deinking processes. This study explores the deinking efficiencies of bacterial alkalophilic laccase (L) and xylanase (X) enzymes along with physical deinking methods of microwaving (MW) and sonication (S) for recycling of old newsprint (ONP). Methods and Results: The operational parameters viz. enzyme dose, pH and treatment time for X and L deinking were optimized statistically using Response Surface Methodology. Laccase did not require any mediator supplementation for deinking. Deinking of ONP pulp with a combination of xylanase and laccase enzymes was investigated, and fiber surface composition and morphological changes were studied using X-ray diffraction, fourier transform infrared spectroscopy and scanning electron microscopy. Compared to the pulp deinked with xylanase (47.9%) or laccase (62.2%) individually, the percentage reduction of effective residual ink concentration (ERIC) was higher for the combined xylanase/laccase-deinked pulp (65.8%). An increase in brightness (21.6%), breaking length (16.5%), burst factor (4.2%) tear factor (6.9%), viscosity (13%) and cellulose crystallinity (10.3%) along with decrease in kappa number (22%) and chemical consumption (50%) were also observed. Surface appeared more fibrillar along with changes in surface functional groups. A combination of physical and enzymatic processes (S-MW-XL) for deinking further improved brightness (28.8%) and decreased ERIC (73.9%) substantially. Conclusion: This is the first report on deinking of ONP with laccase without any mediator supplementation. XL pretreatment resulted in marked improvement in paper quality and a new sequence being reported for deinking (S-MW-XL) will contribute further in decreasing chemical consumption and making the process commercially feasible. [ABSTRACT FROM AUTHOR]

Hydrophilic knotwood extracts from 18 wood species were assessed in disc diffusion and liquid culture tests for antibacterial effects against three species of paper mill bacteria. The Pinus sylvestris, P. resinosa, P. contorta, and P. banksiana extracts decreased or inhibited bacterial growth. The susceptibility order was P. sylvestris > P. resinosa > P. contorta > P. banksiana, correlating with the concentrations of pinosylvin and pinosylvin monomethyl ether in these wood species. Also, Pseudotsuga menziesii and Thuja occidentalis extracts had a small inhibitory effect. The Gram-positive Bacillus coagulans was more susceptible to the extracts than the Gram-negative Burkholderia multivorans and Alcaligenes xylosoxydans. The main components in the Pinus knotwood extracts were pinosylvin monomethyl ether and pinosylvin, suggesting these to be the active components. Therefore, pure pinosylvin, pinosylvin monomethyl ether, and dihydro-pinosylvin monomethyl ether were also tested. All compounds showed antibacterial effects. However, higher concentrations were needed for these pure compounds than for the knotwood extracts. Pinosylvin had stronger antibacterial effects than pinosylvin monomethyl ether. This work shows that knotwood extracts, especially from Pinus species, have a potential for use as natural biocides in papermaking. [ABSTRACT FROM AUTHOR]

The treatment of sludge obtained from a process of waste water treatment depends on treatment itself and final disposal and can cost up to one third of the total expenses of waste water treatment. The use of sludge as well as the use of other manures produced from secondary raw materials in agriculture has been subject of controversial discussions for many years. The main aim of this study was to determine physico-chemical and microbiological characteristics of sludge, and based on the quality of sludge to determine whether it is possible to use it in the composting process and in agriculture. This study suggests that the composting is one of the possible solutions of sludge treatment in "Natron-Hayat" factory. After treating and conditioning of sludge, it can be used in the compost production or in agriculture. It is recommended to use the sludge obtained from the secondary tank or surplus sludge after the biological waste water treatment for the compost production. The daily amount of the sludge is estimated to 10 tons. [ABSTRACT FROM AUTHOR]

The authors assessed the potential of Nigerian currency notes to act as environmental vehicles for the transmission of pathogenic parasites and bacteria. Currency notes obtained from four major cities in Nigeria were evaluated according to standard techniques. Fifty-four (21.6 percent [95 percent CI: 16.50-26.70]) of the first batch of 250 notes, which underwent parasitological analysis, were contaminated with enteric parasites; 133 (53.2 percent [95 percent CI: 47.02-59.39]) of the second batch of 250 notes, which underwent bacteriological analysis, were found to be contaminated with bacteria. Parasites that were isolated from the notes included Ascaris lumbricoides (8.0 percent), Enterobias vermicularis (6.8 percent), Trichuris trichilira (2.8 percent), and Taenia species (4.0 percent). Bacteria that were isolated were Streptococcus species (21.6 percent), Staphylococcus species (12.8 percent), Escherichia coil (13.2 percent), and Bacillus species (5.6 percent). Among dirty/mutilated currency notes, parasite contamination and bacterial contamination were both significantly (p < .05) more pervasive (30.6 percent and 73.8 percent, respectively) than they were among clean and mint currency notes. Lower-denomination notes were more likely to be contaminated than were higher-denomination notes, although the difference was not statistically significant (p > .05). Parasite contamination and bacteria contamination were both most frequent in notes obtained from butchers and beggars. These results suggest that currency notes may be contaminated, especially with bacteria and enteric parasites, and may serve as sources of infection. Personal hygiene to reduce risk of infection is recommended. [ABSTRACT FROM AUTHOR]

Abstract: Surfactants, both chemical and biological, are amphiphilic compounds which can reduce surface and interfacial tensions by accumulating at the interface of immiscible fluids and increase the solubility, mobility, bioavailability and subsequent biodegradation of hydrophobic or insoluble organic compounds. Investigations on their impacts on microbial activity have generally been limited in scope to the most common and best characterized surfactants. Recently a number of new biosurfactants have been described and accelerated advances in molecular and cellular biology are expected to expand our insights into the diversity of structures and applications of biosurfactants. Biosurfactants play an essential natural role in the swarming motility of microorganisms and participate in cellular physiological processes of signaling and differentiation as well as in biofilm formation. Biosurfactants also exhibit natural physiological roles in increasing bioavailability of hydrophobic molecules and can complex with heavy metals, and some also possess antimicrobial activity. Chemical- and indeed bio-surfactants may also be added exogenously to microbial systems to influence behaviour and/or activity, mimicking the latter effects of biosurfactants. They have been exploited in this way, for example as antimicrobial agents in disease control and to improve degradation of chemical contaminants. Chemical surfactants can interact with microbial proteins and can be manipulated to modify enzyme conformation in a manner that alters enzyme activity, stability and/or specificity. Both chemical- and bio-surfactants are potentially toxic to specific microbes and may be exploited as antimicrobial agents against plant, animal and human microbial pathogens. Because of the widespread use of chemical surfactants, their potential impacts on microbial communities in the environment are receiving considerable attention. [Copyright &y& Elsevier]

Abstract: Drinking water is becoming a scarce resource in many areas and both use of water and wastewater outlet are of major ecological and economical importance in many countries. Consumption and discharge may be considerably minimized by means of water reuse. The food industry has a large consumption of water, but until now very limited reuse has taken place due to legislations constraints and hygienic concerns. Legal space for use of water of qualities other than drinking water has been opened with the current legislation. This will, however, in many cases require careful analyses of individual cases based on a thorough understanding of the hazards involved in order to avoid compromising the safety of the food product and thereby the health of consumers. Implementation of water reuse practices in the food industry presents a great challenge for both companies and public health authorities regarding knowledge, technical expertise and documentation. Regulatory, technological, monitoring, verification and ethical aspects associated with microbiologically safe reuse of water in the food industry are discussed and some examples of the challenges ahead and possible approaches are given. [Copyright &y& Elsevier]

This article seeks to address some of the broader ontological and epistemological issues which frequently remain unexplored in debates about evolutionary theory. Debates surrounding evolutionary theory; perhaps particularly those focused on issues of sex and gender, frequently involve contestations over whether a particular behaviour or trait is naturally or socio-culturally determined. Typically, neo-Darwinists explanations posit natural evolutionary processes of natural or (naturalized) sexual selection of human or animal predispositions, traits and behaviours inherited through intra-and inter-cellular processes which, by definition of their "microbiological nature" are, at least implicitly, assumed to be beyond the influence of cultures, histories or politics. Behaviours and traits explained in this way are thus framed as natural whilst the evolutionary explanation itself, positioned within a natural science discourse, is most frequently both articulated and heard as "scientific"-neutral, apolitical and objective.

A multidisciplinary approach to microbiological implications of indoor air is fruitful for research as well as management of health and building problems. The Finnish and the Danish mold programs are examples of such productive collaborative studies. Dust samples taken from classrooms in schools where occupants complain of building-related symptoms (BRS) demonstrated an inflammatory potential in vitro, measured as a release of cytokine interleukin (IL)-8. An increase of the metabolite NO and liberation of tumor necrosis factor (TNF)-α and other cytokines during exposure were obtained in vivo, was presented based on these programs and on epidemiological studies on residential fungal contamination and health conducted in Canada and The Netherlands, New methods for assessing fungal exposure are PCA analysis for the toxigenic mold Stachybotrys chartarum and EPS-Asp/Pen for detecting of Aspergillus and Penicillium in dust. Based on a limited data set it is shown that emission rates of fungal spores are inversely proportional to relative humidity (RH), directly related to flow rate and to surface loading. Poor maintenance, risk constructions and risk materials are described in several studies as the main causes of water damage in buildings. [ABSTRACT FROM AUTHOR]

This document is a correction for an article titled "Vibrio fischeri Possesses Xds and Dns Nucleases That Differentially Influence Phosphate Scavenging, Aggregation, Competence, and Symbiotic Colonization of Squid." The correction addresses specific experiments that were repeated and confirms the previous findings regarding the nuclease activity of the xds mutant strain. The timing of measurable Dns activity was found to vary slightly, but these results do not change the conclusions of the original publication. The corrected and republished paper is available for further reference. [Extracted from the article]

The nature and extent of deterioration of four categories of library materials (news prints, textbooks, dissertations and journals) at Olabisi Onabanjo University Library, Ago-Iwoye, Ogun State, Nigeria was investigated. The pH, fold endurance and the extent of mutilation were determined, while the microorganisms associated with decomposing library materials were isolated and identified. The library materials with acidic papers constituted 69.0% for textbooks, 52.2% for journals, 73.2% for dissertations and 85.3% for newspapers. About 93% of textbooks, 98% of journals and 89% of dissertations did not break up to six folds. The percentage of mutilated books was 11.9% for textbooks, 5.7% for journals and 10.4% for dissertations. The microorganisms associated with deteriorating library materials were Bacillus sp., Streptococcus sp. Staphylococcus sp., Pseudomonas sp. and Flavobacterion sp. for bacteria, while the moulds included Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Penicillium sp., Cladosporium sp., Neurospora sp, Penicillium sp and Rhizopus sp. The ability of these microorganisms to degrade (utilise) native cellulose (filter papers) was investigated so as to be able to know whether these Organisms could actually deteriorate papers. All the moulds except Neurospora sp. effectively utilised filter papers than the two bacterial species Bacillus sp. and Pseudomonas sp. that also degraded filter papers. A. niger and A. flavus most utilised the filter papers for growth among the moulds. Apart from the deteriorative effect, the health implications of the presence of microorganisms particularly the moulds on library materials to library users are discussed. [ABSTRACT FROM AUTHOR]

• Coupling of demographic and environmental noise balances the effect of selection. • Fast switching effectively reduces the selection intensity. • New fixation scenarios: success depends on environmental variability. • EN makes the RPS competition more egalitarian, but does not prolong coexistence. Rock-paper-scissors games metaphorically model cyclic dominance in ecology and microbiology. In a static environment, these models are characterized by fixation probabilities obeying two different "laws" in large and small well-mixed populations. Here, we investigate the evolution of these three-species models subject to a randomly switching carrying capacity modeling the endless change between states of resources scarcity and abundance. Focusing mainly on the zero-sum rock-paper-scissors game, equivalent to the cyclic Lotka–Volterra model, we study how the coupling of demographic and environmental noise influences the fixation properties. More specifically, we investigate which species is the most likely to prevail in a population of fluctuating size and how the outcome depends on the environmental variability. We show that demographic noise coupled with environmental randomness "levels the field" of cyclic competition by balancing the effect of selection. In particular, we show that fast switching effectively reduces the selection intensity proportionally to the variance of the carrying capacity. We determine the conditions under which new fixation scenarios arise, where the most likely species to prevail changes with the rate of switching and the variance of the carrying capacity. Random switching has a limited effect on the mean fixation time that scales linearly with the average population size. Hence, environmental randomness makes the cyclic competition more egalitarian, but does not prolong the species coexistence. We also show how the fixation probabilities of close-to-zero-sum rock-paper-scissors games can be obtained from those of the zero-sum model by rescaling the selection intensity. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a simple, rapid, and low-cost “paper-bridged” method for Salmonella phase reversal. More than 3500 isolates were tested in our laboratory, and the results indicated that this paper-bridged method is a useful alternative for phase reversal. [Copyright &y& Elsevier]

The paper presents the results of a study aimed at evaluating whether prolonged consumption of a probiotic drink consisting of protective microorganisms (lactobacilli, enterococci, and bifidobacteria) and fermented from Saccaromyces would be beneficial to the human microbiological status and function of gastrointestinal tract (GIT). Ten volunteers (two males and eight females above 50 years of age) consumed the drink over the period of 3 months. We investigated microbiota of the intestine, upper airway (UA), and vagina (in females). Microbial samples from the intestine and UA were gathered four times: a week prior to the experiment and then every 30 days. Samples of the vaginal discharge were taken 7–10 days prior to the experiment and 7–10 after its completion. Evaluation of the gastric emptying function, hydrochloric acid production, fasting volume of the gastric juice, and GIT electrical activity was also performed at these time points. The experiment revealed positive trends of the intestinal microbiota. Changes in the species and quantitative composition of the UA microbiota were less pronounced as in the first half of the experiment changes in the UA microbiota were more like negative and displayed a marked positive trend in the second half. After the course of probiotic prophylaxis, colonization of the vagina and cervical channel by opportunistic microorganisms was reduced in six out of eight females. In addition, the probiotic drink stabilized the electrical activity of all GIT components and enhanced intestinal peristalsis. [ABSTRACT FROM AUTHOR]