9,928 research outputs found

    An investigation into the mechanism underlying enhanced hydrolysis of complex carbon in a biosulphidogenic recycling sludge bed reactor (RSBR)

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    The potential for using readily available and cost-effective complex carbon sources such as primary sewage sludge for a range of biological processes, including the bioremediation of acid mine drainage, has been constrained by the slow rate of solubilisation and low yield of soluble products, which drive the above mentioned processes. Previous research into the hydrolysis of complex organic matter, such as primary sludge, under biosulphidogenic conditions within a novel Recycling Sludge Bed Reactor (RSBR) demonstrated solubilisation in excess of 50%. However, further investigation was required into the mechanism of this enhanced hydrolysis. The current study was aimed at confirming that hydrolysis is enhanced under biosulphidogenic conditions, and to obtain an estimate of the relative rates of hydrolysis using toluene as a specific metabolic inhibitor. The solubilisation of primary sewage sludge under sulphate reducing conditions was conducted in controlled flask studies and previously reported findings of enhanced hydrolysis were confirmed. The maximum percentage solubilisation obtained in this study over a 10-day period was 31% and 64% for the methanogenic and sulphidogenic systems respectively. By using toluene as an inhibitor of bacterial uptake of soluble carbohydrates, it was possible to determine the rate of production of various key products of the hydrolytic step. From the results of the current experiment, the rate of production of soluble carbohydrate, and therefore the rate of hydrolysis of complex carbohydrates, in terms of COD equivalents was estimated at 543 mgCOD·l-1·d-1 and 156 mgCOD·l- 1·d-1 under sulphidogenic and methanogenic conditions, respectively.. Water SA Vol. 30 (5) 2005: pp.150-15

    A test-retest fMRI dataset for motor, language and spatial attention functions

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    Background Since its inception over twenty years ago, functional magnetic resonance imaging (fMRI) has been used in numerous studies probing neural underpinnings of human cognition. However, the between session variance of many tasks used in fMRI remains understudied. Such information is especially important in context of clinical applications. A test-retest dataset was acquired to validate fMRI tasks used in pre-surgical planning. In particular, five task-related fMRI time series (finger, foot and lip movement, overt verb generation, covert verb generation, overt word repetition, and landmark tasks) were used to investigate which protocols gave reliable single-subject results. Ten healthy participants in their fifties were scanned twice using an identical protocol 2–3 days apart. In addition to the fMRI sessions, high-angular resolution diffusion tensor MRI (DTI), and high-resolution 3D T1-weighted volume scans were acquired. Findings Reliability analyses of fMRI data showed that the motor and language tasks were reliable at the subject level while the landmark task was not, despite all paradigms showing expected activations at the group level. In addition, differences in reliability were found to be mostly related to the tasks themselves while task-by-motion interaction was the major confounding factor. Conclusions Together, this dataset provides a unique opportunity to investigate the reliability of different fMRI tasks, as well as methods and algorithms used to analyze, de-noise and combine fMRI, DTI and structural T1-weighted volume data

    Quantifying Global Drivers of Zoonotic Bat Viruses: A Process-based Perspective

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    Emerging infectious diseases (EIDs), particularly zoonoses, represent a significant threat to global health. Emergence is often driven by anthropogenic activity (e.g. travel, land use change). Although disease emergence frameworks suggest multiple steps from initial zoonotic transmission to human-to-human spread, there have been few attempts to empirically model specific steps. We create a process-based framework to separate out components of individual emergence steps. We focus on early emergence and expand the first step, zoonotic transmission, into processes of generation of pathogen richness, transmission opportunity and establishment, each with their own hypothesised drivers. Using this structure, we build a spatial empirical model of these drivers, taking bat viruses shared with humans as a case study. We show that drivers of both viral richness (host diversity and climatic variability) and transmission opportunity (human population density, bushmeat hunting and livestock production) are associated with virus sharing between humans and bats. We also show spatial heterogeneity between the global patterns of these two processes, suggesting high priority locations for pathogen discovery and surveillance in wildlife may not necessarily coincide with those for public health intervention. Finally, we offer direction for future studies of zoonotic EIDs by highlighting the importance of the processes underlying their emergence

    Mobile health as a primary mode of intervention for women at risk of, or diagnosed with, gestational diabetes mellitus: a scoping review.

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    OBJECTIVE: The objective of this review was to map the knowledge related to the use of mHealth as a primary mode of intervention for the prevention and management of gestational diabetes mellitus and its long-term implications among women at risk of or diagnosed with gestational diabetes mellitus. We also sought to understand if mHealth for women at risk of or diagnosed with gestational diabetes mellitus incorporated relevant behavior change theory and techniques. INTRODUCTION: Prevention and management of gestational diabetes mellitus and its associated adverse outcomes are important to maternal and infant health. Women with gestational diabetes mellitus report high burden of disease management and barriers to lifestyle change post-delivery, which mHealth interventions may help to overcome. Evidence suggests apps could help gestational diabetes mellitus prevention and management, however, less is known about broader applications of mHealth from preconception to interconception and whether relevant behavior change techniques are incorporated. INCLUSION CRITERIA: Studies published in English that focused on mHealth use as primary mode of intervention for the prevention and management of gestational diabetes mellitus and its long-term implications were considered for inclusion. Telehealth or telemedicine were excluded as these have been reviewed elsewhere. METHODS: Six databases were searched: MEDLINE (Ovid), CINAHL (EBSCO), Embase (Ovid), Cochrane Database (Wiley), Scopus, and TRIP. No limits were applied to database exploration periods to ensure retrieval of all relevant studies. Gray literature sources searched were OpenGrey, ISRCTN Registry, ClinicalTrials.gov, EU Clinical Trials Register, and ANZCTR. Two reviewers independently screened abstracts and assessed full texts against the inclusion criteria. Data were extracted using an adapted version of the JBI data extraction instrument. Data are presented in narrative form accompanied by tables and figures. RESULTS: This review identified 2166 sources, of which 96 full texts were screened. Thirty eligible reports were included, covering 25 different mHealth interventions. Over half (n = 14) were for self-managing blood glucose during pregnancy. Common features included tracking blood glucose levels, real-time feedback, communication with professionals, and educational information. Few (n = 6) mHealth interventions were designed for postpartum use and none for interconception use. Five for postpartum use supported behavior change to reduce the risk of type 2 diabetes and included additional features such as social support functions and integrated rewards. Early development and feasibility studies used mixed methods to assess usability and acceptability. Later stage evaluations of effectiveness typically used randomized controlled trial designs to measure clinical outcomes such as glycemic control and reduced body weight. Three mHealth interventions were developed using behavior change theory. Most mHealth interventions incorporated two behavior change techniques shown to be optimal when combined and those delivering behavior change interventions included a wider range. Nevertheless, only half of the 26 techniques listed in a published behavior change taxonomy were tried. CONCLUSIONS: mHealth for gestational diabetes mellitus focuses on apps to improve clinical outcomes. This focus could be broadened by incorporating existing resources that women value, such as social media, to address needs, such as peer support. Although nearly all mHealth interventions incorporated behavior change techniques, findings suggest future development should consider selecting techniques that target women's needs and barriers. Lack of mHealth interventions for prevention of gestational diabetes mellitus recurrence and type 2 diabetes mellitus suggests further development and evaluation is required

    Internalized and Anticipated Stigmatization in Patients With Gout

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    OBJECTIVE: To investigate the relationship between stigma perception and demographic, clinical, and psychosocial variables. METHODS: A sample of 50 patients with gout and prescribed urate‐lowering medication (84% were males, mean serum urate 0.34 mmol/l) completed questionnaires on internalized and anticipated stigma, demographics, clinical gout‐related variables, and psychosocial variables (illness perceptions, illness‐related disability, illness‐related body satisfaction, intentional nonadherence). Serum urate level was obtained from the most recent blood test. RESULTS: In this sample, 26% experienced internalized stigma, 26% expected to be stigmatized by friends or family members, and 14% by health care workers. Univariate regression analyses showed that younger age, ethnicity other than New Zealand European, increased severity of gout pain, cognitive and emotional illness perceptions, greater illness‐related disability, and increased intentional nonadherence to urate‐lowering medication were associated with increased internalized and anticipated stigma. Younger age, emotional illness response, and intentional nonadherence were the only variables explaining incremental variance of the experience of anticipated stigma in a multivariate regression model. CONCLUSION: Internalized and anticipated illness‐related stigma was reported by a subgroup of patients with gout. The experience of stigma is associated with younger age, a negative emotional illness response, and intentions to not adhere with a medical treatment

    Draft genome sequences of Achromobacter piechaudii GCS2, Agrobacterium sp. Strain SUL3, Microbacterium sp. Strain GCS4, Shinella sp. Strain GWS1, and Shinella sp. Strain SUS2 isolated from Consortium with the Hydrocarbon-Producing Alga Botryococcus braunii.

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    This is the final version of the article. Available from American Society for Microbiology via the DOI in this record.A variety of bacteria associate with the hydrocarbon-producing microalga Botryococcus braunii, some of which may influence its growth. We report here the genome sequences for Achromobacter piechaudii GCS2, Agrobacterium sp. strain SUL3, Microbacterium sp. strain GCS4, and Shinella sp. strains GWS1 and SUS2, isolated from a laboratory culture of B. braunii, race B, strain Guadeloupe.K.J.J. was funded by a Ph.D. studentship from the Biotechnology and Biologaical Sciences Research Council (BBSRC) LoLa award BB/ K003240/2. The Exeter Sequencing Service was supported by the Wellcome Trust Institutional Strategic Support Fund (WT097835MF), a Wellcome Trust Multi User Equipment Award (WT101650MA), and a BBSRC LoLa award (BB/K003240/2). We gratefully acknowledge the Exeter Sequencing Service and computational core facilities at the University of Exete

    Synthetic metabolic pathways for photobiological conversion of CO2 into hydrocarbon fuel

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    Liquid fuels sourced from fossil sources are the dominant energy form for mobile transport today. The consumption of fossil fuels is still increasing, resulting in a continued search for more sustainable methods to renew our supply of liquid fuel. Photosynthetic microorganisms naturally accumulate hydrocarbons that could serve as a replacement for fossil fuel, however productivities remain low. We report successful introduction of five synthetic metabolic pathways in two green cell factories, prokaryotic cyanobacteria and eukaryotic algae. Heterologous thioesterase expression enabled high-yield conversion of native fatty acyl-acyl carrier protein (ACP) into free fatty acids (FFA) in Synechocystis sp. PCC 6803 but not in Chlamydomonas reinhardtii where the polar lipid fraction instead was enhanced. Despite no increase in measurable FFA in Chlamydomonas, genetic recoding and over-production of the native fatty acid photodecarboxylase (FAP) resulted in increased accumulation of 7-heptadecene. Implementation of a carboxylic acid reductase (CAR) and aldehyde deformylating oxygenase (ADO) dependent synthetic pathway in Synechocystis resulted in the accumulation of fatty alcohols and a decrease in the native saturated alkanes. In contrast, the replacement of CAR and ADO with Pseudomonas mendocina UndB (so named as it is responsible for 1-undecene biosynthesis in Pseudomonas) or Chlorella variabilis FAP resulted in high-yield conversion of thioesterase-liberated FFAs into corresponding alkenes and alkanes, respectively. At best, the engineering resulted in an increase in hydrocarbon accumulation of 8- (from 1 to 8.5 mg/g cell dry weight) and 19-fold (from 4 to 77 mg/g cell dry weight) for Chlamydomonas and Synechocystis, respectively. In conclusion, reconstitution of the eukaryotic algae pathway in the prokaryotic cyanobacteria host generated the most effective system, highlighting opportunities for mix-and-match synthetic metabolism. These studies describe functioning synthetic metabolic pathways for hydrocarbon fuel synthesis in photosynthetic microorganisms for the first time, moving us closer to the commercial implementation of photobiocatalytic systems that directly convert CO2 into infrastructure-compatible fuels

    Evidence that cytokine-mediated immune interactions induced by Schistosoma mansoni alter disease outcome in mice concurrently infected with Trichuris muris.

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    In murine models of Schistosoma mansoni infection, egg production is associated with a switch from T helper cell (Th)1- to Th2-type responses to both schistosome-specific and unrelated antigens. Polyparasitism is common in human populations within S. mansoni endemic areas. We have, therefore, examined whether coinfection with S. mansoni could affect the outcome of a second parasitic infection, through Th2 cytokine-dependent modifications to the host immune response. We find that when mice susceptible to infection with the gut nematode Trichuris muris are coinfected with S. mansoni, they acquire the capacity to resolve T. muris infection, thus demonstrating a resistant phenotype. This ability to expel T. muris is associated with the production of Th2-associated cytokines, and corresponding antibody isotypes, in response to S. mansoni egg antigens. The Th2 response shows that there is no compartmentalization between spleen and mesenteric lymph nodes, and that the expulsion of T. muris is not caused by any changes in the host intestine associated with excretion of schistosome eggs. This influence of schistosome infections may be important, not only for the outcome of infections with unrelated pathogens in endemic areas, but also for the efficacy of vaccines in such areas

    Implementing Affordable Socially Assistive Pet Robots in Care Homes Before and During the COVID-19 Pandemic: Stratified Cluster Randomized Controlled Trial and Mixed Methods Study.

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    BACKGROUND: Robot pets may assist in the challenges of supporting an aging population with growing dementia prevalence. Prior work has focused on the impacts of the robot seal Paro on older adult well-being, but recent studies have suggested the good acceptability and implementation feasibility of more affordable devices (Joy for All [JfA] cats and dogs). OBJECTIVE: We aimed to address the limited effectiveness research on JfA devices. METHODS: We conducted an 8-month, stratified, cluster randomized controlled trial in 8 care homes in Cornwall, United Kingdom. Over 4 months, 4 care homes each received 2 JfA devices (1 cat and 1 dog; intervention group), and 4 homes received care as usual (control group). Psychometrics were collected before and after the intervention to compare the change from baseline to follow-up between the groups. In the final 4 months, all 8 care homes received devices, but only qualitative data were collected owing to COVID-19 and reduced capacity. The primary outcome was neuropsychiatric symptoms (Neuropsychiatric Inventory [NPI] Nursing Home version). Care provider burden was a secondary outcome (occupational disruptiveness NPI subscale), alongside the Challenging Behavior scale, the Holden communication scale, the Campaign to End Loneliness questionnaire, and medication use. Qualitative data were collected through care staff observation calendars and end-of-study interviews to understand use, experience, and impact. We also collected demographic data and assessed dementia severity. In total, 253 residents had robot interaction opportunities, and 83 were consented for direct data collection. RESULTS: There was a significant difference in the total change from baseline to follow-up between the intervention and control groups for NPI (P<.001) and occupational disruptiveness (P=.03). Neuropsychiatric symptoms increased in the control group and decreased in the intervention group. No significant difference was seen for communication issues or challenging behavior. For NPI subdomains, there were significant differences from baseline to follow-up in delusions (P=.03), depression (P=.01), anxiety (P=.001), elation (P=.02), and apathy (P=.009), all of which decreased in the intervention group and increased slightly in the control group. The summative impact results suggested that most residents (46/54, 85%) who interacted with robots experienced a positive impact. Those who interacted had significantly higher dementia severity scores (P=.001). The qualitative results suggested good adoption, acceptability, and suitability for subjectively lonely individuals and lack of a novelty effect through sustained use, and demonstrated that the reasons for use were entertainment, anxiety, and agitation. CONCLUSIONS: Affordable robot pets hold potential for improving the well-being of care home residents and people with dementia, including reducing neuropsychiatric symptoms and occupational disruptiveness. This work suggests no novelty effect and contributes toward understanding robot pet suitability. Moreover, interactions were more common among residents with more moderate/severe dementia and those subjectively lonely. TRIAL REGISTRATION: ClinicalTrials.gov NCT04168463; https://www.clinicaltrials.gov/ct2/show/NCT0416846
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