34 research outputs found
Effects of aquatic vegetation type on denitrification
In a microcosm 15N enrichment experiment we tested the effect of floating vegetation (Lemna sp.) and submerged vegetation (Elodea nuttallii) on denitrification rates, and compared it to systems without macrophytes. Oxygen concentration, and thus photosynthesis, plays an important role in regulating denitrification rates and therefore the experiments were performed under dark as well as under light conditions. Denitrification rates differed widely between treatments, ranging from 2.8 to 20.9 µmol N m-2 h-1, and were strongly affected by the type of macrophytes present. These differences may be explained by the effects of macrophytes on oxygen conditions. Highest denitrification rates were observed under a closed mat of floating macrophytes where oxygen concentrations were low. In the light, denitrification was inhibited by oxygen from photosynthesis by submerged macrophytes, and by benthic algae in the systems without macrophytes. However, in microcosms with floating vegetation there was no effect of light, as the closed mat of floating plants caused permanently dark conditions in the water column. Nitrate removal was dominated by plant uptake rather than denitrification, and did not differ between systems with submerged or floating plant
Adult obesity and the burden of disability throughout life
OBJECTIVE: To analyze the prevalence of disability throughout life and
life expectancy free of disability, associated with obesity at ages 30 to
49 years. RESEARCH METHODS AND PROCEDURES: We used 46 and 20 years of
mortality follow-up, respectively, for 3521 Original and 3013 Offspring
Framingham Heart Study participants 30 to 49 years and classified as
normal weight, overweight, or obese at baseline. Disability measures were
available between 36 and 46 years of follow-up for 1352 Original
participants and at 20 years of follow-up for 2268 Offspring participants.
We measured the odds of disability in the Original cohort after 46 years
follow-up, and we estimated life expectancy with and without disability
from age 50. Two disability measures were used, one representing
limitations with mobility only and the second representing limitations
with activities of daily living (ADL). RESULTS: Obesity at ages 30 to 49
years was associated with a 2.01-fold increase in the odds of ADL
limitations 46 years later. Nonsmoking adults who were obese between 30
and 49 years lived 5.70 (95% confidence interval, 4.11 to 7.35) (men) and
5.02 (95% confidence interval, 3.36 to 6.61) (women) fewer years free of
ADL limitations from age 50 than their normal-weight counterparts. There
was no significant difference in the total number of years lived with
disability throughout life between those obese or normal weight, due to
both higher disability prevalence and higher mortality in the obese
population. DISCUSSION: Obesity in adulthood is associated with an
increased risk of disability throughout life and a reduction in the length
of time spent free of disability, but no substantial change in the length
of time spent with disability
Osteoporosis care during the COVID-19 pandemic in the Netherlands: a national survey
This is a survey study concerning osteoporosis care during the COVID-19 pandemic in the Netherlands. Respondents reported that osteoporosis care stagnated and lower quality of care was provided. This leads to the conclusion that standardization of osteoporosis care delivery in situations of crisis is needed.Purpose: During the initial phase of the COVID-19 pandemic, there was no guidance of professional societies or guidelines on the organization of osteoporosis care in case of such a crisis, and treatment relied on local ad hoc strategies. Experiences from the current pandemic need to be taken into account for the near future, and therefore, a national multidisciplinary survey was carried out in the Netherlands.Methods: A survey of 17 questions concerning the continuation of bone mineral density measurements by Dual Energy X-ray absorptiometry (DXA), outpatient clinic visits, and prescription of medication was sent to physicians, nurses, nurse practitioners, and physician assistants working in the field of osteoporosis.Results: 77 respondents finished the questionnaire, of whom 39 (50.6%) reported a decline in DXA-scanning and 36 (46.8%) no scanning at all during the pandemic. There was an increase in remote consultations for both new and control patient visits (n = 48, 62.3%; n = 62, 81.7% respectively). Lower quality of care regarding fracture prevention was reported by more than half of the respondents (n = 44, 57.1%). Treatment with intravenous bisphosphonates and denosumab was delayed according to 35 (45.4%) and 6 (6.3%) of the respondents, respectively.Conclusion: During the COVID-19 pandemic, osteoporosis care almost completely arrested, especially because of the discontinuation of DXA-scanning and closing of outpatient clinics. More than half of the respondents reported a substantial lower quality of osteoporosis care during the COVID pandemic. To prevent an increase in fracture rates and a decrease in patient motivation, adherence and satisfaction, standardization of osteoporosis care delivery in situations of crisis is needed.Diabetes mellitus: pathophysiological changes and therap
Validity of the Patient Experiences and Satisfaction with Medications (PESaM) Questionnaire
Background: This study assessed the validity and reliability of the generic module of the recently developed Patient Experiences and Satisfaction with Medications (PESaM) questionnaire in a sample of patients in the Netherlands. Methods: The generic module of the PESaM questionnaire consists of 18 items related to the domains effectiveness, side effects and ease of use of medications. It assesses patients’ experiences regarding the impact of the medication on daily life, health and satisfaction. In 2017, the PESaM questionnaire was sent out to idiopathic pulmonary fibrosis patients using pirfenidone or nintedanib, atypical haemolytic uraemic syndrome patients receiving eculizumab and patients using tacrolimus after kidney transplantation. Mean scores for each domain were calculated applying a scoring algorithm. Construct validity and reliability were assessed using recommended methods. Results: 188 participants completed the generic module, of whom 48% used pirfenidone, 36% nintedanib, 11% tacrolimus and 5% eculizumab. The generic module has good structural properties. Internal consistency values of the domains were satisfactory (i.e. Cronbach’s coefficient alpha above 0.7). Confirmatory factor analysis provided further evidence for construct validity, with good convergent and discriminant validity. The PESaM questionnaire also showed different scores for patients using different medications, in line with expectations, and was therefore able to differentiate between patient groups. Test–retest reliability of the items and domains were rated as moderate to fair (i.e. intraclass coefficients ranged between 0.18 and 0.76). Conclusions: The PESaM questionnaire is a unique patient-reported outcome measure evaluating patient experiences and satisfaction with medications. It has been developed in conjunction with patients, ensuring coverage of domains and issues relevant from the patient’s perspective. This study has shown promising validity of the generic module of the PESaM questionnaire. Further research is recommended to assess reliability in greater detail as well as the responsiveness of the measure. Trial registration: The study