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Introduction Cognitive functioning and psychological well-being are considered negatively affected by COVID-19. An estimated 15%-40% of COVID-19 patients report disrupted cognitive performance. Higher rates of anxiety, depression and sleep disturbances are also reported post infection. Objectives We examined the profile of cognitive changes in a group of adults with a confirmed COVID-19 diagnosis, compared to those without a COVID-19 diagnosis (cross-sectional between-subjects investigation); and for a subgroup, compared to their pre-COVID-19 cognitive function (longitudinal within-subjects investigation). Methods One hundred and twenty-one adults (57 with no known history of COVID-19; 64 with confirmed COVID-19; 17/64 with long COVID symptoms) were assessed online for psychological well-being and cognitive function (attention, processing speed, working memory, episodic memory and executive function). Pre-COVID-19 cognitive data were available for 56 of 121 adults (24 adults with a confirmed diagnosis of COVID-19; 22 with no known history of COVID-19) through the MyCognition database. Results The COVID-19 group showed reduced processing speed in both cross-sectional and longitudinal investigations, and also showed significant attentional impairment when examined cross-sectionally. Five long COVID symptoms (abdominal pain, chest pain, sore eyes/conjunctivitis, sore throat and vomiting/nausea) were associated with reduced performance in multiple cognitive domains. Higher levels of depression and anxiety were also present in the COVID-19 group but these symptoms were mostly unrelated to cognitive performance. Conclusions COVID-19 survivors, especially those with long COVID symptoms, are very likely to experience cognitive disruption. Measures need to be implemented to support their cognitive recovery in addition to the physical recovery. Disclosure No significant relationships.

In this paper, we discuss a joint approach to calibration and uncertainty estimation for hydrologic systems that combines a top-down, data-based mechanistic (DBM) modelling methodology; and a bottom-up, reductionist modelling methodology. The combined approach is applied to the modelling of the River Hodder catchment in North-West England. The top-down DBM model provides a well identified, statistically sound yet physically meaningful description of the rainfall-flow data, revealing important characteristics of the catchment-scale response, such as the nature of the effective rainfall nonlinearity and the partitioning of the effective rainfall into different flow pathways. These characteristics are defined inductively from the data without prior assumptions about the model structure, other than it is within the generic class of nonlinear differential-delay equations. The bottom-up modelling is developed using the TOPMODEL, whose structure is assumed a priori and is evaluated by global sensitivity analysis (GSA) in order to specify the most sensitive and important parameters. The subsequent exercises in calibration and validation, performed with Generalized Likelihood Uncertainty Estimation (GLUE), are carried out in the light of the GSA and DBM analyses. This allows for the pre-calibration of the the priors used for GLUE, in order to eliminate dynamical features of the TOPMODEL that have little effect on the model output and would be rejected at the structure identification phase of the DBM modelling analysis. In this way, the elements of meaningful subjectivity in the GLUE approach, which allow the modeler to interact in the modelling process by constraining the model to have a specific form prior to calibration, are combined with other more objective, data-based benchmarks for the final uncertainty estimation. GSA plays a major role in building a bridge between the hypothetico-deductive (bottom-up) and inductive (top-down) approaches and helps to improve the calibration of mechanistic hydrological models, making their properties more transparent. It also helps to highlight possible mis-specification problems, if these are identified. The results of the exercise show that the two modelling methodologies have good synergy; combining well to produce a complete joint modelling approach that has the kinds of checks-and-balances required in practical data-based modelling of rainfall-flow systems. Such a combined approach also produces models that are suitable for different kinds of application. As such, the DBM model considered in the paper is developed specifically as a vehicle for flow and flood forecasting (although the generality of DBM modelling means that a simulation version of the model could be developed if required); while TOPMODEL, suitably calibrated (and perhaps modified) in the light of the DBM and GSA results, immediately provides a simulation model with a variety of potential applications, in areas such as catchment management and planning.

Human noroviruses (HuNoVs), a leading cause of food-borne gastroenteritis worldwide, are easily transferred via ready-to-eat (RTE) foods, often prepared by infected food handlers. In this study, the transmission of HuNoV and murine norovirus (MuNoV) from virus-contaminated hands to latex gloves during gloving, as well as from virus-contaminated donor surfaces to recipient surfaces after simulated preparation of cucumber sandwiches, was inspected. Virus transfer was investigated by swabbing with polyester swabs, followed by nucleic acid extraction from the swabs with a commercial kit and quantitative reverse transcription-PCR. During gloving, transfer of MuNoV dried on the hand was observed 10/12 times. HuNoV, dried on latex gloves, was disseminated to clean pairs of gloves 10/12 times, whereas HuNoV without drying was disseminated 11/12 times. In the sandwich-preparing simulation, both viruses were transferred repeatedly to the first recipient surface (left hand, cucumber, and knife) during the preparation. Both MuNoV and HuNoV were transferred more efficiently from latex gloves to cucumbers (1.2% ± 0.6% and 1.5% ± 1.9%) than vice versa (0.7% ± 0.5% and 0.5% ± 0.4%). We estimated that transfer of at least one infective HuNoV from contaminated hands to the sandwich prepared was likely to occur if the hands of the food handler contained 3 log10 or more HuNoVs before gloving. Virus-contaminated gloves were estimated to transfer HuNoV to the food servings more efficiently than a single contaminated cucumber during handling. Our results indicate that virus-free food ingredients and good hand hygiene are needed to prevent HuNoV contamination of RTE foods., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Human norovirus (HuNoV), which causes gastroenteritis, can be transmitted to food and food contact surfaces via viruscontaminated hands. To investigate this transmission in food processing environments, we developed a swabbing protocol for environmental samples, evaluated the stability of HuNoV in the swabs, and applied the method in the food industry. Swabs made of polyester, flocked nylon, cotton wool, and microfiber were moistened in either phosphate-buffered saline (PBS) or glycine buffer (pH 9.5) and used to swab four surfaces (latex, plastic, stainless steel, and cucumber) inoculated with HuNoV. HuNoV was eluted with either PBS or glycine buffer and detected with quantitative reverse transcription PCR. HuNoV recoveries were generally higher with an inoculation dose of 100 PCR units than 1,000 PCR units. The highest recoveries were obtained when surfaces were swabbed with microfiber cloth moistened in and eluted with glycine buffer after a HuNoV inoculation dose of 100 PCR units: 66% ± 18% on latex, 89% ±2% on plastic, and 79% ±10% on stainless steel. The highest recovery for cucumber, 45% ±5%, was obtained when swabbing the surface with microfiber cloth and PBS. The stability of HuNoV was tested in microfiber cloths moistened in PBS or glycine buffer. HuNoV RNA was detected from swabs after 3 days at 4 and 22°C, although the RNA levels decreased more rapidly in swabs moistened with glycine buffer than in those moistened with PBS at 22°C. In the field study, 172 microfiber and 45 cotton wool swab samples were taken from environmental surfaces at three food processing companies. Five (5.6%) of 90 swabs collected in 2010 and 7 (8.5%) of 82 swabs collected in 2012 were positive for HuNoV genogroup II; all positive samples were collected with microfiber swabs. Three positive results were obtained from the production line and nine were obtained from the food workers' break room and restroom areas. Swabbing is a powerful tool for HuNoV RNA detection from environmental surfaces and enables investigation of virus transmission during food processing.

Three cutinase gene-like genes from the basidiomycete Coprinopsis cinerea (Coprinus cinereus) found with a similarity search were cloned and expressed in Trichoderma reesei under the control of an inducible cbh1 promoter. The selected transformants of all three polyesterase constructs showed activity with p-nitrophenylbutyrate, used as a model substrate. The most promising transformant of the cutinase CC1G_09668.1 gene construct was cultivated in a laboratory fermentor, with a production yield of 1.4 g liter(-l) purified protein. The expressed cutinase (CcCUT1) was purified to homogeneity by immobilized metal affinity chromatography exploiting a C-terminal His tag. The N terminus of the enzyme was found to be blocked. The molecular mass of the purified enzyme was determined to be around 18.8 kDa by mass spectrometry. CcCUT1 had higher activity on shorter (C(2) to C(10)) fatty acid esters of p-nitrophenol than on longer ones, and it also exhibited lipase activity. CcCUT1 had optimal activity between pH 7 and 8 but retained activity over a wide pH range. The enzyme retained 80% of its activity after 20 h of incubation at 50 degrees C, but residual activity decreased sharply at 60 degrees C. Microscopic analyses and determination of released hydrolysis products showed that the enzyme was able to depolymerize apple cutin and birch outer bark suberin.

In this study, polysaccharide-producing bacteria were isolated from slimes collected from two Finnish and one Spanish paper mill and the exopolysaccharides (EPSs) produced by 18 isolates were characterised. Most of the isolates, selected on the bases of slimy colony morphology, were members of the family Enterobacteriaceae most frequently belonging to the genera Enterobacter and Klebsiella including Raoultella. All of the EPSs analysed showed the presence of charged groups in the form of uronic acid or pyruvate revealing the polyanionic nature of these polysaccharides. Further results of the carbohydrate analysis showed that the EPS produced by nine of the enterobacteria was colanic acid.

Development of novel enzymatic methods for slime deposit control in paper mills requires knowledge of polysaccharide-producing organisms and the polysaccharide structures present in deposits. In this work, 27 polysaccharide-producing bacteria were isolated from slime samples collected from different parts of a paper machine. Most of the isolates produced polysaccharides in liquid culture and nine of them were selected for production of polysaccharides for characterisation. The selected isolates belonged to seven different genera: Bacillus, Brevundimonas, Cytophaga, Enterobacter, Klebsiella, Paenibacillus and Starkeya. Using ribotyping, partial 16S rDNA sequencing, physiological tests and fatty acid analysis, four of the nine isolates: Bacillus cereus, Brevundimonas vesicularis, K. pneumoniae and P. stellifer were identified to the species level. Production of polysaccharides by the selected isolates varied between 0.07 and 1.20 g L(-1), the highest amount being produced by B. vesicularis. The polysaccharides were heteropolysaccharides with varying proportions of galactose, glucose mannose, rhamnose fucose and uronic acids.

Bacterial strains were isolated from spruce wood chips and their ability to reduce the content of wood extractives was studied. Strains were screened by cultivation on liquid media containing wood extractives as the major nutrient. Some bacterial species could decrease remarkably the amount of extractives in the liquid media and reduced the amount of triglycerides, steryl esters and total extractives by 100, 20 and 39%, respectively. Spruce wood chips were treated in controlled conditions with selected bacteria to test their effects on the chips. All the bacteria grew well on wood chips. The effect of bacterial metabolism on wood extractives was significant. Bacterial treatments reduced the amount of lipophilic extractives by 16-38% in 1 week of treatment and up to 67% in 2 weeks. The most efficient strain removed 90, 66 and 50% of triglycerides, steryl esters and resin acids, respectively, in 2 weeks. These results indicate that bacteria may be promising agents for the removal of extractives for improved pulping and papermaking processes.

An efficient transformation system for the cellulolytic filamentous fungus Trichoderma reesei has been developed. Transformation was obtained with plasmid carrying the dominant selectable marker amdS or the argB gene of Aspergillus nidulans, which was found to complement the respective argB mutation of T. reesei. The transformation frequency can be up to 600 transformants per microgram of transforming DNA. The efficiency of co-transformation with unselected DNA was high (approx. 80%). The transforming DNA was found to be integrated at several different locations, often in multiple tandem copies in the T. reesei genome. In addition, the Escherichia coli beta-galactosidase was expressed in T. reesei in enzymatically active form from the A. nidulans gpd promoter.