881 research outputs found
Inhibition of microbial sulfate reduction in a flow-through column system by (per)chlorate treatment.
Microbial sulfate reduction is a primary cause of oil reservoir souring. Here we show that amendment with chlorate or perchlorate [collectively (per)chlorate] potentially resolves this issue. Triplicate packed columns inoculated with marine sediment were flushed with coastal water amended with yeast extract and one of nitrate, chlorate, or perchlorate. Results showed that although sulfide production was dramatically reduced by all treatments, effluent sulfide was observed in the nitrate (10 mM) treatment after an initial inhibition period. In contrast, no effluent sulfide was observed with (per)chlorate (10 mM). Microbial community analyses indicated temporal community shifts and phylogenetic clustering by treatment. Nitrate addition stimulated Xanthomonadaceae and Rhizobiaceae growth, supporting their role in nitrate metabolism. (Per)chlorate showed distinct effects on microbial community structure compared with nitrate and resulted in a general suppression of the community relative to the untreated control combined with a significant decrease in sulfate reducing species abundance indicating specific toxicity. Furthermore, chlorate stimulated Pseudomonadaceae and Pseudoalteromonadaceae, members of which are known chlorate respirers, suggesting that chlorate may also control sulfidogenesis by biocompetitive exclusion of sulfate-reduction. Perchlorate addition stimulated Desulfobulbaceae and Desulfomonadaceae, which contain sulfide oxidizing and elemental sulfur-reducing species respectively, suggesting that effluent sulfide concentrations may be controlled through sulfur redox cycling in addition to toxicity and biocompetitive exclusion. Sulfur isotope analyses further support sulfur cycling in the columns, even when sulfide is not detected. This study indicates that (per)chlorate show great promise as inhibitors of sulfidogenesis in natural communities and provides insight into which organisms and respiratory processes are involved
Microbial Community Structures of Novel Icelandic Hot Spring Systems Revealed by PhyloChip G3 Analysis
Microbial community profiles of recently formed hot spring systems ranging in temperatures from 57°C to 100°C and pH values from 2 to 4 in HveragerĂ°i (Iceland) were analyzed with PhyloChip G3 technology. In total, 1173 bacterial operational taxonomic units (OTUs) spanning 576 subfamilies and 38 archaeal OTUs covering 32 subfamilies were observed. As expected, the hyperthermophilic (100°C) spring system exhibited both low microbial biomass and diversity when compared to thermophilic (60°C) springs. Ordination analysis revealed distinct bacterial and archaeal diversity in geographically distinct hot springs. Slight variations in temperature (from 57°C to 64°C) within the interconnected pools led to a marked fluctuation in microbial abundance and diversity. Correlation and PERMANOVA tests provided evidence that temperature was the key environmental factor responsible for microbial community dynamics, while pH, H_(2)S, and SO_2 influenced the abundance of specific microbial groups. When archaeal community composition was analyzed, the majority of detected OTUs correlated negatively with temperature, and few correlated positively with pH. Key Words: Microbial diversityâPhyloChip G3âAcidophilicâThermophilicâHot springsâIceland. Astrobiology 14, xxxâxxx
Changes in presentations with features potentially indicating cancer in primary care during the COVID-19 pandemic:a retrospective cohort study
OBJECTIVES: To investigate how the COVID-19 pandemic affected the number of people aged 50+ years presentingâto primary care with features that could potentially indicate cancer, and to explore how reporting differed by patient characteristics and in face-to-face vs remote consultations. DESIGN, SETTING AND PARTICIPANTS: A retrospective cohort study of general practitioner (GP), nurse and paramedic primary care consultations in 21 practices in South-West England covering 123â947 patients. The models compared potential cancer indicators reported in AprilâJuly 2019 with AprilâJuly 2020. MAIN OUTCOME MEASURES: Potential indicators of cancer were identified using code lists for symptoms, signs, test results and diagnoses listed in the National Institute for Health and Care Excellence suspected cancer referral guidance (NG12). RESULTS: During AprilâJuly 2019, 17% of registered patients aged 50+ years reported a potential cancer indicator in a consultation with a GP or nurse. During AprilâJuly 2020, this reduced to 11% (incidence rate ratio (IRR) 0.64, 95%âCI 0.62 to 0.67, p<0.001). Reductions in potential cancer indicators were stable across age group, sex, ethnicity, index of multiple deprivation quintile and shielding status, but less marked in patients with mental health conditions than without (IRR 0.75, 95%âCI 0.72 to 0.79, interaction p<0.001). Proportions of GP consultations with potential indicators of cancer reduced between 2019 and 2020 for face-to-face consultations (IRR 0.84, 95%âCI 0.76 to 0.92, p<0.001) and increased for remote consultations (IRR 1.17, 95%âCI 1.07 to 1.29, p=0.001), although it remained lower in remote consulting than face-to-face in AprilâJuly 2020. This difference was greater for nurse/paramedic consultations (face-to-face: IRR 0.61, 95%âCI 0.44 to 0.83, p=0.002; remote: IRR 1.60, 95%âCI 1.10 to 2.333, p=0.014). CONCLUSION: The number of patients consulting with presentations that could potentially indicate cancer reduced during the first wave of the COVID-19 pandemic. Patients should be encouraged to continue contacting primary care for persistent signs and symptoms, and GPs and nurses should be encouraged to probe patients for further information during remote consulting, in the absence of non-verbal cues
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Qwu?gwes - A Squaxin Island tribal heritage wet site, Puget Sound, USA
The Qwu?gwes wet site is located at the very head of Puget Sound in Washington State, USA (fig 1). Puget Sound has been referred to as an inland sea, but is better termed as a large glacially cut fjord that is approximately 145km long, running north to south, where the ocean salt water from the Pacific mixes with fresh water draining from the surrounding watersheds. Puget Sound was formed into the northâsouth fjord it is today by glaciers that advanced from the north at least four times, scouring and carving it for millions of years (Waitt & Thorson 1983). The Vashon Stade was the last major advance, reaching its maximum about 18,000 years ago, covering everything between the Olympic and the Cascade mountains and spreading as far south as our specific region of study. As the Vashon Stade retreated, its melting ice created a massive fresh water lake that released through the Black Lake spillway at the head of Eld Inlet, our site location, and down the Chehalis River drainage to the Pacific Ocean. Once the glaciers melted far enough north, the Straits of Juan de Fuca were open and salt water from the Pacific Ocean entered Puget Sound, making it the salt water âinland seaâ it is today (fig 1). Our research area encompasses the southern reaches of the traditional territory of the Lushootseed-speaking Coast Salish People and language family, sometimes referred to as Puget [Sound] Salish (Suttles & Lane 1990, 485â502; Thompson & Kinkade 1990, 38; fig 1). Few systematic archaeological investigations have occurred in this region, especially in the southern section of Lushootseed traditional territory, so this paper should be considered a much needed synthesis of a well-preserved waterlogged site. Qwu?gwes forms the main reference point for our synthesized presentations, and this work is based on the original papers presented by the authors at the 11th International Wetland Archaeology Research Project (WARP) conference in Edinburgh (21â24 September 2005). This joint investigation of the Squaxin Island Tribe and South Puget Sound Community College has been ongoing for several years and provides both a scientific and cultural perspective of the many findings. Earlier publications stress the basis of this joint co-operative effort and the need for co-ordinated scientific and Native cultural understandings and explanations (Foster & Croes 2002, 2004)
Illness management and recovery in community practice
Objective
To examine provider competence in providing Illness Management and Recovery (IMR), an evidence-based self-management program for people with severe mental illness, and the association between implementation supports and IMR competence.
Methods
IMR session recordings, provided by 43 providers/provider pairs, were analyzed for IMR competence using the IMR treatment integrity scale. Providers also reported on receipt of commonly available implementation supports (e.g., training, consultation).
Results
Average IMR competence scores were in the âNeeds Improvementâ range. Clinicians demonstrated low competence in several IMR elements: significant other involvement, weekly action planning, action plan follow-up, cognitive-behavioral techniques, and behavioral tailoring for medication management. These elements were commonly absent from IMR sessions. Competence in motivational enhancement strategies and cognitive-behavioral techniques differed based on the module topic covered in a session. Generally, receipt of implementation supports was not associated with increased competence; however, motivational interviewing training was associated with increased competence in action planning and review.
Conclusions and Implications for Practice
IMR, as implemented in the community, may lack adequate competence and commonly available implementation supports do not appear to be adequate. Additional implementation supports that target clinician growth areas are needed
A novel human iPSC model of COL4A1/A2 small vessel disease unveils a key pathogenic role of matrix metalloproteinases
Cerebral small vessel disease (SVD) affects the small vessels in the brain and is a leading cause of stroke and dementia. Emerging evidence supports a role of the extracellular matrix (ECM), at the interface between blood and brain, in the progression of SVD pathology, but this remains poorly characterized. To address ECM role in SVD, we developed a co-culture model of mural and endothelial cells using human induced pluripotent stem cells from patients with COL4A1/A2 SVD-related mutations. This model revealed that these mutations induce apoptosis, migration defects, ECM remodeling, and transcriptome changes in mural cells. Importantly, these mural cell defects exert a detrimental effect on endothelial cell tight junctions through paracrine actions. COL4A1/A2 models also express high levels of matrix metalloproteinases (MMPs), and inhibiting MMP activity partially rescues the ECM abnormalities and mural cell phenotypic changes. These data provide a basis for targeting MMP as a therapeutic opportunity in SVD.</p
Time-restricted feeding improves adaptation to chronically alternating light-dark cycles
Disturbance of the circadian clock has been associated with increased risk of cardio-metabolic disorders. Previous studies showed that optimal timing of food intake can improve metabolic health. We hypothesized that time-restricted feeding could be a strategy to minimize long term adverse metabolic health effects of shift work and jetlag. In this study, we exposed female FVB mice to weekly alternating light-dark cycles (i.e. 12 h shifts) combined with ad libitum feeding, dark phase feeding or feeding at a fixed clock time, in the original dark phase. In contrast to our expectations, long-term disturbance of the circadian clock had only modest effects on metabolic parameters. Mice fed at a fixed time showed a delayed adaptation compared to ad libitum fed animals, in terms of the similarity in 24 h rhythm of core body temperature, in weeks when food was only available in the light phase. This was accompanied by increased plasma triglyceride levels and decreased energy expenditure, indicating a less favorable metabolic state. On the other hand, dark phase feeding accelerated adaptation of core body temperature and activity rhythms, however, did not improve the metabolic state of animals compared to ad libitum feeding. Taken together, restricting food intake to the active dark phase enhanced adaptation to shifts in the light-dark schedule, without significantly affecting metabolic parameters
What are the type, direction, and strength of species, community, and ecosystem responses to warming in aquatic mesocosm studies and their dependency on experimental characteristics? A systematic review protocol
Background
Mesocosm experiments have become increasingly popular in climate change research as they bridge the gap between small-scale, less realistic, microcosm experiments, and large-scale, more complex, natural systems. Characteristics of aquatic mesocosm designs (e.g., mesocosm volume, study duration, and replication) vary widely, potentially affecting the magnitude and direction of effect sizes measured in experiments. In this global systematic review we aim to identify the type, direction and strength of climate warming effects on aquatic species, communities and ecosystems in mesocosm experiments. Furthermore, we will investigate the context-dependency of the observed effects on several a priori determined effect moderators (ecological and methodological). Our conclusions will provide recommendations for aquatic scientists designing mesocosm experiments, as well as guidelines for interpretation of experimental results by scientists, policy-makers and the general public.
Methods
We will conduct a systematic search using multiple online databases to gather evidence from the scientific literature on the effects of warming experimentally tested in aquatic mesocosms. Data from relevant studies will be extracted and used in a random effects meta-analysis to estimate the overall effect sizes of warming experiments on species performance, biodiversity and ecosystem functions. Experimental characteristics (e.g., mesocosm size and shape, replication-level, experimental duration and design, biogeographic region, community type, crossed manipulation) will be further analysed using subgroup analyses
Ecological Dissertations in the Aquatic Sciences: An Effective Networking and Professional Development Opportunity for Early Career Aquatic Scientists
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