151 research outputs found
Chloride levels increase after 13 years of recycled water use in the Salinas Valley
The use of recycled water for agriculture is a long-term water strategy in California.
A study in the 1980s in Monterey County showed recycled water increased soil salinity
but not to a level unacceptable for agriculture. Most growers in the northern Salinas
Valley have been using it since 1998, and yet providers of the water and many growers
are concerned that the sustained use of recycled water might cause deterioration of
the soil. An ongoing study, initiated in 2000, compares the changes in soil salinity
between a field receiving only well water and eight fields that receive recycled water.
In 13 years of data, the average soil salinity parameters at each site were highly
correlated with the average water quality values of the recycled water. Soil salinity
did increase, though not deleteriously. Of most concern was the accumulation of chloride
at four of the sites, to levels above the critical threshold values for chloride-sensitive
crops
Realidades morales. ensayo de psicologÃa filosófica
Traducción de Ana Isabel Stellino y Antonio Zirión. México: UNAM - Instituto de Investigaciones Filosóficas, 1998. 259 pp. ISBN 968-853-374-2
Plato on Well-Being
Plato's dialogues use several terms for the concept of well-being, which concept plays a central ethical role as the ultimate goal for action and a central political role as the proper aim for states. But the dialogues also reveal sharp debate about what human well-being is. I argue that they endorse a Socratic conception of well-being as virtuous activity, by considering and rejecting several alternatives, including an ordinary conception that lists a variety of goods, a Protagorean conception that identifies one's well-being with what appears one to be one's well-being, and hedonistic conceptions
Clinical trials registries are under-utilized in the conduct of systematic reviews: a cross-sectional analysis
Abstract Background Publication bias is a major threat to the validity of systematic reviews. Searches of clinical trials registries can help to identify unpublished trials, though little is known about how often these resources are utilized. We assessed the usage and results of registry searches reported in systematic reviews published in major general medical journals. Methods This cross-sectional analysis includes data from systematic reviews assessing medical interventions which were published in one of six major general medical journals between July 2012 and June 2013. Two authors independently examined each published systematic review and all available supplementary materials to determine whether at least one clinical trials registry was searched. Results Of the 117 included systematic reviews, 41 (35%) reported searching a trials registry. Of the 29 reviews which also provided detailed registry search results, 15 (52%) identified at least one completed trial and 18 (62%) identified at least one ongoing trial. Conclusions Clinical trials registry searches are not routinely included in systematic reviews published in major medical journals. Routine examination of registry databases may allow a more accurate characterization of publication and outcome reporting biases and improve the validity of estimated effects of medical treatments
Peer Reviewed Evaluation of Registered End-Points of Randomised Trials (the PRE-REPORT study): a stepped wedge, cluster-randomised trial.
OBJECTIVE: To test whether providing relevant clinical trial registry information to peer reviewers evaluating trial manuscripts decreases discrepancies between registered and published trial outcomes.
DESIGN: Stepped wedge, cluster-randomised trial, with clusters comprised of eligible manuscripts submitted to each participating journal between 1 November 2018 and 31 October 2019.
SETTING: Thirteen medical journals.
PARTICIPANTS: Manuscripts were eligible for inclusion if they were submitted to a participating journal during the study period, presented results from the primary analysis of a clinical trial, and were peer reviewed.
INTERVENTIONS: During the control phase, there were no changes to pre-existing peer review practices. After journals crossed over into the intervention phase, peer reviewers received a data sheet describing whether trials were registered, the initial registration and enrolment dates, and the registered primary outcome(s) when enrolment began.
MAIN OUTCOME MEASURE: The presence of a clearly defined, prospectively registered primary outcome consistent with the primary outcome in the published trial manuscript, as determined by two independent outcome assessors.
RESULTS: We included 419 manuscripts (243 control and 176 intervention). Participating journals published 43% of control-phase manuscripts and 39% of intervention-phase manuscripts (model-estimated percentage difference between intervention and control trials = -10%, 95% CI -25% to 4%). Among the 173 accepted trials, published primary outcomes were consistent with clearly defined, prospectively registered primary outcomes in 40 of 105 (38%) control-phase trials and 27 of 68 (40%) intervention-phase trials. A linear mixed model did not show evidence of a statistically significant primary outcome effect from the intervention (estimated difference between intervention and control=-6% (90% CI -27% to 15%); one-sided p value=0.68).
CONCLUSIONS: These results do not support use of the tested intervention as implemented here to increase agreement between prospectively registered and published trial outcomes. Other approaches are needed to improve the quality of outcome reporting of clinical trials.
TRIAL REGISTRATION NUMBER: ISRCTN41225307
The discovery of potent, selective, and reversible inhibitors of the house dust mite peptidase allergen Der p 1: an innovative approach to the treatment of allergic asthma.
Blocking the bioactivity of allergens is conceptually attractive as a small-molecule therapy for allergic diseases but has not been attempted previously. Group 1 allergens of house dust mites (HDM) are meaningful targets in this quest because they are globally prevalent and clinically important triggers of allergic asthma. Group 1 HDM allergens are cysteine peptidases whose proteolytic activity triggers essential steps in the allergy cascade. Using the HDM allergen Der p 1 as an archetype for structure-based drug discovery, we have identified a series of novel, reversible inhibitors. Potency and selectivity were manipulated by optimizing drug interactions with enzyme binding pockets, while variation of terminal groups conferred the physicochemical and pharmacokinetic attributes required for inhaled delivery. Studies in animals challenged with the gamut of HDM allergens showed an attenuation of allergic responses by targeting just a single component, namely, Der p 1. Our findings suggest that these inhibitors may be used as novel therapies for allergic asthma
Malnutrition Among Cognitively Intact, Noncritically Ill Older Adults in the Emergency Department
We estimate the prevalence of malnutrition among older patients presenting to an emergency department (ED) in the southeastern United States and identify subgroups at increased risk
Non-publication of large randomized clinical trials: cross sectional analysis
Objective To estimate the frequency with which results of large randomized clinical trials registered with ClinicalTrials.gov are not available to the public.Design Cross sectional analysisSetting Trials with at least 500 participants that were prospectively registered with ClinicalTrials.gov and completed prior to January 2009.Data sources PubMed, Google Scholar, and Embase were searched to identify published manuscripts containing trial results. The final literature search occurred in November 2012. Registry entries for unpublished trials were reviewed to determine whether results for these studies were available in the ClinicalTrials.gov results database.Main outcome measures The frequency of non-publication of trial results and, among unpublished studies, the frequency with which results are unavailable in the ClinicalTrials.gov database.Results Of 585 registered trials, 171 (29%) remained unpublished. These 171 unpublished trials had an estimated total enrollment of 299 763 study participants. The median time between study completion and the final literature search was 60 months for unpublished trials. Non-publication was more common among trials that received industry funding (150/468, 32%) than those that did not (21/117, 18%), P=0.003. Of the 171 unpublished trials, 133 (78%) had no results available in ClinicalTrials.gov.Conclusions Among this group of large clinical trials, non-publication of results was common and the availability of results in the ClinicalTrials.gov database was limited. A substantial number of study participants were exposed to the risks of trial participation without the societal benefits that accompany the dissemination of trial results
Ambulance transport rates after motor vehicle collision for older vs. younger adults: A population-based study
Older adults are at greater risk than younger adults for life-threatening injury after motor vehicle collision (MVC). Among those with life-threatening injury, older adults are also at greater risk of not being transported by emergency medical services (EMS) to an emergency department. Despite the greater risk of serious injury and non-transportation among older adults, little is known about the relationship between patient age and EMS transportation rates for individuals experiencing MVC. We describe transport rates across the age-span for adults seen by EMS after experiencing MVC using data reported to the North Carolina Department of Motor Vehicles between 2008 and 2011. Of all adults aged 18 years and older experiencing MVC and seen by EMS (N=484,310), 36.3% (N=175,768) were transported to an emergency department. Rates of transport for individuals seen by EMS after MVC increased only a small amount with increasing patient age. After adjusting for potential confounders of the relationship between patient age and the decision to transport (patient gender, patient race, air bag deployment, patient trapped or ejected, and injury severity), transport rates were: age 18–64 = 36.0% (95% Confidence Interval [CI], 35.9%–36.2%); age 65–74 = 36.6% (95% CI, 36.0%–37.1%); age 75–84 = 37.3% (95% CI, 36.5%–38.1%), and age 85–94 = 38.2% (95% CI, 36.7%–39.8%). In North Carolina between 2008 and 2011, the transportation rate was only slightly higher for older adults than for younger adults, and most older adults experiencing MVC and seen by EMS were not transported to the emergency department. These findings have implications for efforts to improve the sensitivity of criteria used by EMS to determine the need for transport for older adults experiencing MVC
Effectiveness of 99mTc-tetrofosmin for assessment of heart functions in micropigs
This study examined the suitability of a nuclear imaging technique using 99mTc-tetrofosmin as an agent to assess the heart functions of healthy micropigs. The mean age of the pigs was 360 days (male), and the mean body weight was 35.3 kg ranging from 34.5-36 kg. There were no significant perfusion defects in any of the reconstructed images. Gated single-photon emission computed tomography imaging can be used to calculate the ventricular volume and ejection fraction (EF). In this case, an EF of 79% was calculated from the ventricular volume of the end-systolic image (10 ml) subtracted from that of the end-diastolic volume (49 ml). A perfusion defect (particularly the apex, lateral wall) is unlikely because of the presence of a preserved wall motion in a segment with a defect. It is concluded that quantitative cardiac scintigraphy, using 99mTc-tetrofosmin is an adequate technique for estimating the heart functions of healthy micropigs
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