349 research outputs found
Phosphorus Cycling in the Sargasso Sea: Investigation Using the Oxygen Isotopic Composition of Phosphate, Enzyme-Labeled Fluorescence, and Turnover Times
Dissolved inorganic phosphorus (DIP) concentrations in surface water of vast areas of the ocean are extremely low (\u3c10 nM) and phosphorus (P) availability could limit primary productivity in these regions. We explore the use of oxygen isotopic signature of dissolved phosphate (ÎŽ18OPO4) to investigate biogeochemical cycling of P in the Sargasso Sea, Atlantic Ocean. Additional techniques for studying P dynamics including 33P-based DIP turnover time estimates and percent of cells expressing alkaline phosphatase (AP) activity as measured by enzyme-labeling fluorescence are also used. In surface waters, ÎŽ18OPO4 values were lower than equilibrium by 3â6%, indicative of dissolved organic phosphorous (DOP) remineralization by extracellular enzymes. An isotope mass balance model using a variety of possible combinations of enzymatic pathways and substrates indicates that DOP remineralization in the euphotic zone can account for a large proportion on P utilized by phytoplankton (as much as 82%). Relatively short DIP turnover times (4â8 h) and high expression of AP (38â77% of the cells labeled) are consistent with extensive DOP utilization and low DIP availability in the euphotic zone. In deep water where DOP utilization rates are lower, ÎŽ18OPO4 values approach isotopic equilibrium and DIP turnover times are longer. Our data suggests that in the euphotic zone of the Sargasso Sea, DOP may be appreciably remineralized and utilized by phytoplankton and bacteria to supplement cellular requirements. A substantial fraction of photosynthesis in this region is supported by DOP uptake
Evaluation of Attention Process Training and Brain Injury Education in Persons with Acquired Brain Injury
Sleep Hygiene and Problem Behaviors in Snoring and Non- Snoring School-Age Children
ObjectivesâThe effects of sleep-disordered breathing, sleep restriction, dyssomnias, and parasomnias on daytime behavior in children have been previously assessed. However, the potential relationship(s) between sleep hygiene and childrenâs daytime behavior remain to be explored. The primary goal of this study was to investigate the relationship between sleep hygiene and problematic behaviors in non-snoring and habitually snoring children.
MethodsâParents of 100 5- to 8-year-old children who were reported to snore âfrequentlyâ to âalmost always,â and of 71 age-, gender-, and ethnicity-matched children who were reported to never snore participated in this study. As part of a larger, ongoing study, children underwent nocturnal polysomnography and parents were asked to complete the Childrenâs Sleep Hygiene Scale (CSHS) and the Connersâ Parent Rating Scales-Revised (CPRS-R:L).
ResultsâIn the snoring group, strong negative correlations (r = â.39, p
ConclusionsâParental reports of behavioral patterns in snoring children indicate that poorer sleep hygiene is more likely to be associated with behavior problems, including hyperactivity, impulsivity, and oppositional behavior. In contrast, no significant relationships between slee
2001 Wild Blueberry CSREES Project Reports
The 2001 edition of the Wild Blueberry CSREES Progress Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Effect of Wild Blueberry Products on Oxidation in Meat Based Food Systems
2. Factors Affecting the Microbial and Pesticide Residues Levels on Wild Blueberries
3. Determination of Pesticide Residue Levels in Fresh and Processed Wild Blueberries
4. Separation of Maggot-Infested Wild Blueberries in the IQF Processing Line
5. Water Use of Wild Blueberries and the Impact of Plant Water Stress on Yields
6. Survey of Stem Blight and Leaf Spot Diseases in Wild Blueberry Fields
7. IPM Strategies
8. Control Tactics for Wild Blueberry Pest Insects, 2001
9. Biology and Ecology of Blueberry Pest Insects
10. Diurnal Bee Activity and Measurement of Honeybee Field Strength
11. Effect of Foliar-applied Iron (Fe) Chelate Concentration on Leaf Iron Concentration, Wild Blueberry Growth and Yield
12. Effect of Boron Application Methods on Boron Uptake in Wild Blueberries
13. Effect of Foliar Iron and Copper Application on Growth and Yield of Wild Blueberries
14. Effect of Fertilizer Timing on Wild Blueberry Growth and Productivity
15. Effect of Foliar Copper Application on Growth and Yield of Wild Blueberries
16. Effect of Prune-year Applications of Nutri-Phitetm P or Nutri-Phitetm P+K on Growth and Yield of Wild Blueberry (Vaccinium angustifolium Ait.)
17. Effect of Soil pH on Nutrient Uptake
18. Assessment of Azafenidin for Weed Control in Wild Blueberries
19. Assessment of Rimsulfuron for Weed Control in Wild Blueberries
20. Assessment of Pendimethalin for Weed Control in Wild Blueberries
21. Evaluation and Demonstration of Techniques for Filling in Bare Spots in Wild Blueberry Fields
22. Assessment of Sprout-less Weeder for Hardwood Control in Wild Blueberries
23. Wild Blueberry Extension Education Program in 2001
24. Evaluation of Fungicide Efficacy in Wild Blueberry Fields
25. 2001 Pesticide Groundwater Survey
26. Cultural Weed Management Using Sulfur to Lower the pH
27. Wild Blueberry Web Sit
Cost effectiveness of first-line oral therapies for pulmonary arterial hypertension: A modelling study
Background: In recent years, a significant number of costly oral therapies have become available for the treatment of pulmonary arterial hypertension (PAH). Funding decisions for these therapies requires weighing up their effectiveness and costs. Objective: The aim of this study was to assess the cost effectiveness of monotherapy with oral PAH-specific therapies versus supportive care as initial therapy for patients with functional class (FC) II and III PAH in Canada. Methods: A cost-utility analysis, from the perspective of a healthcare system and based on a Markov model, was designed to estimate the costs and quality-adjusted life-years (QALYs) associated with bosentan, ambrisentan, riociguat, tadalafil, sildenafil and supportive care for PAH in treatment-naĂŻve patients. Separate analyses were conducted for cohorts of patients commencing therapy at FC II and III PAH. Transition probabilities, based on the relative risk of improving and worsening in FC with treatment versus placebo, were derived from a recent network meta-analysis. Utility values and costs were obtained from published data and clinical expert opinion. Extensive sensitivity analyses were conducted. Results: Analysis suggests that sildenafil is the most cost-effective therapy for PAH in patients with FC II or III. Sildenafil was both the least costly and most effective therapy, thereby dominating all other treatments. Tadalafil was also less costly and more effective than supportive care in FC II and III; however, sildenafil was dominant over tadalafil. Even given the uncertainty within the clinical inputs, the probabilistic sensitivity analysis showed that apart from sildenafil and tadalafil, the other PAH therapies had negligible probability of being the most cost effective. Conclusion: The results show that initiation of therapy with sildenafil is likely the most cost-effective strategy in PAH patients with either FC II or III disease.This research was supported by funds from the Canadian Agency for Drugs and Technologies in Health (CADTH)
The \u27Healthy Parks-Healthy People\u27 Movement in Canada: Progress, Challenges, and an Emerging Knowledge and Action Agenda
In this article, we outline progress and challenges in establishing effective health promotion tied to visitor experiences provided by protected and conserved areas in Canada. Despite an expanding global evidence base, case studies focused on aspects of health and well-being within Canadaâs protected and conserved areas remain limited. Data pertaining to motivations, barriers and experiences of visitors are often not collected by governing agencies and, if collected, are not made generally available or reported on. There is an obvious, large gap in research and action focused on the needs and rights of groups facing systemic barriers related to a variety of issues including, but not limited to, access, nature experiences, and needs with respect to health and well-being outcomes. Activation of programmes at the site level continue to grow, and Park Prescription programmes, as well as changes to the Accessible Canada Act, represent significant, positive examples of recent cross-sector policy integration. Evaluations of outcomes associated with HPHP programmes have not yet occurred but will be important to adapting interventions and informing cross-sector capacity building. We conclude by providing an overview of gaps in evidence and practice that, if addressed, can lead to more effective human health promotion vis-Ă -vis nature contact in protected and conserved areas in Canada
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Impacts of Coastal Acidification on the Pacific Northwest Shellfish Industry and Adaptation Strategies Implemented in Response
In 2007, the US west coast shellfish industry began to feel the effects of unprecedented levels of larval mortality in commercial hatcheries producing the Pacific oyster Crassostrea gigas. Subsequently, researchers at Whiskey Creek Shellfish Hatchery, working with academic and government scientists, showed a high correlation between aragonite saturation state (Ω[subscript]arag) of inflowing seawater and survival of larval groups, clearly linking increased COâ to hatchery failures. This work led the Pacific Coast Shellfish Growers Association (PCSGA) to instrument shellfish hatcheries and coastal waters, establishing a monitoring network in collaboration with university researchers and the US Integrated Ocean Observing System. Analytical developments, such as the ability to monitor Ω[subscript]arag in real time, have greatly improved the industryâs understanding of carbonate chemistry and its variability and informed the development of commercial-scale water treatment systems. These treatment systems have generally proven effective, resulting in billions of additional oyster larvae supplied to Pacific Northwest oyster growers. However, significant challenges remain, and a multifaceted approach, including selective breeding of oyster stocks, expansion of hatchery capacity, continued monitoring of coastal water chemistry, and improved understanding of biological responses will all be essential to the survival of the US west coast shellfish industry
Relational aggression in adolescents with conduct disorder:sex differences and behavioral correlates
As most research on conduct disorder (CD) has been conducted on male participants, it has been suggested that female-specific symptoms may be underestimated based on current DSM-5 criteria. In particular, relational aggression, i.e. the hurtful, often indirect, manipulation of relationships with the intention of damaging the otherâs social position, has been proposed as a characteristic of CD that is more common in females. In addition, sex-specific studies on correlates of relational aggressive behavior are lacking. Relational aggression may be strongly related to the correlates of proactive aggression, namely low affective empathy, and high levels of callous-unemotional (CU) traits and relational victimization. Thus, the present study investigated sex differences in relational aggression, and associations between relational aggression and correlates of proactive aggression in 662 adolescents with CD (403 females) and 849 typically-developing controls (568 females) aged 9â18Â years (M = 14.74, SD = 2.34) from the European multi-site FemNAT-CD study. Females with CD showed significantly higher levels of relational aggression compared to males with CD, whereas no sex differences were seen in controls. Relational aggression was only partly related to correlates of proactive aggression in CD: Independent of sex, CU traits showed a positive association with relational aggression. In females only, cognitive, but not affective empathy, was negatively associated with relational aggression. Relational victimization was more strongly associated with relational aggression in males compared to females. Despite interesting sex specific correlates of relational aggression, effects are small and the potential clinical implications should be investigated in future studies
The Antenatal Corticosteroids Trial (ACT): a secondary analysis to explore site differences in a multi-country trial
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