403 research outputs found
THE POLITICAL ECONOMY OF WATER QUALITY PROTECTION FROM AGRICULTURAL CHEMICALS
Environmental Economics and Policy,
The Coordination and Design of Point-Nonpoint Trading Programs and Agri-Environmental Policies
Agricultural agencies have long offered agri-environmental payments that are inadequate to achieve water quality goals, and many state water quality agencies are considering point-nonpoint trading to achieve the needed pollution reductions. This analysis considers both targeted and nontargeted agrienvironmental payment schemes, along with a trading program which is not spatially targeted. The degree of improved performance among these policies is found to depend on whether the programs are coordinated or not, whether double-dipping (i.e., when farmers are paid twice-once by each program-to undertake particular pollution control actions) is allowed, and whether the agri-environmental payments are targeted. Under coordination, efficiency gains only occur with double-dipping, so that both programs jointly influence farmers' marginal decisions. Without coordination, doubledipping may increase or decrease efficiency, depending on how the agri-environmental policy is targeted. Finally, double-dipping may not solely benefit farmers, but can result in a transfer of agricultural subsidies to point sources.Environmental Economics and Policy,
An evaluation of active noise control in a cylindrical shell
The physical mechanisms governing the use of active noise control in an extended volume of a cylindrical shell are discussed. Measured data was compared with computer results from a previously derived analytical model based on an infinite shell theory. For both the analytical model and experiment, the radiation of the external monopoles is coupled to the internal acoustic field through the radial displacement of the thin, elastic cylindrical shell. An active noise control system was implemented in the cylinder using a fixed array of discrete monopole sources, all of which lie in the plane of the exterior noise sources. Good agreement between measurement and prediction was obtained for both internal pressure response and overall noise reduction. Attenuations in the source plane greater than 15 dB were recorded along with a uniformly quieted noise environment over the entire length of the experimental model. Results indicate that for extended axial forcing distributions or very low shell damping, axial arrays of control sources may be required. Finally, the Nyquist criteria for the number of azimuthal control sources is shown to provide for effective control over the full cylinder cross section
THE DESIGN AND COMPARATIVE ECONOMIC PERFORMANCE OF ALTERNATIVE SECOND-BEST POINT/NONPOINT TRADING MARKETS
There is considerable interest in the use of pollution trading between point and nonpoint sources to improve the cost-effectiveness of water pollution control, but little literature to guide the design of trading systems involving nonpoint sources. We explore the design of two types of trading systems that would allow trading among and between point and nonpoint sources.Environmental Economics and Policy,
THE VALUE OF ECOLOGICAL AND ECONOMIC INFORMATION IN WATER QUALITY MANAGEMENT
Replaced with revised version of paper 08/25/03.Environmental Economics and Policy,
Comparative Outcomes of Commonly Used Off-Label Atypical Antipsychotics in the Treatment of Dementia-Related Psychosis: A Network Meta-Analysis
Introduction
Dementia-related psychosis (DRP) is characterized by hallucinations and delusions, which may increase the debilitating effects of underlying dementia. This network meta-analysis (NMA) evaluated the comparative efficacy, safety, and acceptability of atypical antipsychotics (AAPs) commonly used off label to treat DRP. Methods
We included 22 eligible studies from a systematic literature review of AAPs (quetiapine, risperidone, olanzapine, aripiprazole, and brexpiprazole) used off label to treat DRP. Study outcomes were: (1) efficacy—neuropsychiatric inventory-nursing home (NPI-NH psychosis subscale), (2) safety—mortality, cerebrovascular events (CVAEs), and others (somnolence, falls, fractures, injuries, etc.), and (3) acceptability—discontinuations due to all causes, lack of efficacy, and adverse events (AEs). We used random-effects modeling to estimate pooled standardized mean differences (SMDs) for NPI-NH psychosis subscale scores and odds ratios (OR) for other dichotomous outcomes, with their respective 95% confidence intervals (CIs). Results
Compared with placebo, aripiprazole (SMD − 0.12; 95% CI − 0.31, 0.06), and olanzapine (SMD − 0.17; 95% CI − 0.04; 0.02) demonstrated small, non-significant numerical improvements in NPI-NH psychosis scores (5 studies; n = 1891), while quetiapine (SMD 0.04; 95% CI − 0.23, 0.32) did not improve symptoms. The odds of mortality (15 studies, n = 4989) were higher for aripiprazole (OR 1.58; 95% CI 0.62, 4.04), brexpiprazole (OR 2.22; 95% CI 0.30, 16.56), olanzapine (OR 2.21; 95% CI 0.84, 5.85), quetiapine (OR 1.68; 95% CI 0.70, 4.03), and risperidone (OR 1.63; 95% CI 0.93, 2.85) than for placebo. Risperidone (OR 3.68; 95% CI 1.68, 8.95) and olanzapine (OR 4.47; 95% CI 1.36, 14.69) demonstrated significantly greater odds of CVAEs compared to placebo. Compared with placebo, odds of all-cause discontinuation were significantly lower for aripiprazole (OR 0.71; 95% CI 0.51, 0.98; 20 studies; 5744 patients) and higher for other AAPs. Aripiprazole (OR 0.5; 95% CI 0.31, 0.82) and olanzapine (OR 0.48; 95% CI 0.31, 0.74) had significantly lower odds of discontinuation due to lack of efficacy (OR 12 studies; n = 4382) compared to placebo, while results for quetiapine and risperidone were not significant. Compared with placebo, the odds of discontinuation due to AEs (19 studies, n = 5445) were higher for olanzapine (OR 2.62; 95% CI 1.75, 3.92), brexpiprazole (OR 1.80; 95% CI 0.80, 4.07), quetiapine (OR 1.25; 95% CI 0.82, 1.91), aripiprazole (OR 1.38; 95% CI 0.90, 2.13), and risperidone (OR 1.41; 95% CI 1.02, 1.94). Conclusions
Overall results demonstrate that, compared with placebo, quetiapine is not associated with improvement in psychosis in patients with dementia, while olanzapine and aripiprazole have non-significant small numerical improvements. These off-label AAPs (quetiapine, risperidone, olanzapine, aripiprazole, and brexpiprazole) are associated with greater odds of mortality, CVAEs, and discontinuations due to AEs than placebo. These results underscore the ongoing unmet need for newer pharmacological options with a more favorable benefit-risk profile for the treatment of DRP
Branch Mode Selection during Early Lung Development
Many organs of higher organisms, such as the vascular system, lung, kidney,
pancreas, liver and glands, are heavily branched structures. The branching
process during lung development has been studied in great detail and is
remarkably stereotyped. The branched tree is generated by the sequential,
non-random use of three geometrically simple modes of branching (domain
branching, planar and orthogonal bifurcation). While many regulatory components
and local interactions have been defined an integrated understanding of the
regulatory network that controls the branching process is lacking. We have
developed a deterministic, spatio-temporal differential-equation based model of
the core signaling network that governs lung branching morphogenesis. The model
focuses on the two key signaling factors that have been identified in
experiments, fibroblast growth factor (FGF10) and sonic hedgehog (SHH) as well
as the SHH receptor patched (Ptc). We show that the reported biochemical
interactions give rise to a Schnakenberg-type Turing patterning mechanisms that
allows us to reproduce experimental observations in wildtype and mutant mice.
The kinetic parameters as well as the domain shape are based on experimental
data where available. The developed model is robust to small absolute and large
relative changes in the parameter values. At the same time there is a strong
regulatory potential in that the switching between branching modes can be
achieved by targeted changes in the parameter values. We note that the sequence
of different branching events may also be the result of different growth
speeds: fast growth triggers lateral branching while slow growth favours
bifurcations in our model. We conclude that the FGF10-SHH-Ptc1 module is
sufficient to generate pattern that correspond to the observed branching modesComment: Initially published at PLoS Comput Bio
Efficacy results of pimavanserin from a multi-center, open-label extension study in Parkinson's disease psychosis patients
This is the final version. Available on open access from Elsevier via the DOI in this recordIntroduction: Pimavanserin, a selective 5-HT2A inverse agonist/antagonist, was
approved for hallucinations and delusions associated with Parkinson’s disease psychosis
(PDP). We present durability of response with pimavanserin in patients with PDP for an
additional 4 weeks of treatment.
Methods: This was an open-label extension (OLE) study in patients previously
completing one of three double-blind, placebo-controlled (Core) studies. All patients
received pimavanserin 34 mg once daily. Efficacy assessments included the Scale for the
Assessment of Positive Symptoms (SAPS) PD and H+D scales, Clinical Global
Impression (CGI) Improvement and Severity scales and Caregiver Burden Scale (CBS),
through 4 weeks in the OLE. Safety assessments were conducted at each visit.
Results: Of 459 patients, 424 (92.4%) had a Week 4 efficacy assessment. At Week 4 (10
weeks total treatment), SAPS-PD mean (standard deviation) change from OLE baseline
was -1.8 (5.5) and for SAPS-H+D was -2.1 (6.2) with pimavanserin 34 mg. Patients
receiving placebo during the Core studies had greater improvements (SAPS-PD -2.9
[5.6]; SAPS-H+D -3.5 [6.3]) during the OLE. For participants treated with pimavanserin
8.5 or 17 mg during the Core studies, further improvement was observed during the OLE
with pimavanserin 34 mg. The mean change from Core Study baseline for SAPS-PD
score was similar among prior pimavanserin 34 mg and prior placebo-treated participants
(-7.1 vs. -7.0). The CGI-I response rate (score of 1 or 2) at Week 4 was 51.4%. Adverse
events were reported by 215 (46.8%) patients during the first 4 weeks of OLE. The most
common AEs were fall (5.9%), hallucination (3.7%), urinary tract infection (2.8%),
insomnia (2.4%), and peripheral edema (2.2%)
4
Conclusions: Patients previously on pimavanserin 34 mg during three blinded core
studies had durability of efficacy during the subsequent 4 week OLE SAPS-PD
assessment. Patients previously on blinded placebo improved after 4 weeks of OL
pimavanserin treatment. These results in over 400 patients from 14 countries support the
efficacy of pimavanserin for treating PDP.ACADIA Pharmaceuticals Inc. (San Diego, CA
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