4,155 research outputs found
Solar system constraints on the Dvali-Gabadadze-Porrati braneworld theory of gravity
A number of proposals have been put forward to account for the observed
accelerating expansion of the Universe through modifications of gravity. One
specific scenario, Dvali-Gabadadze-Porrati (DGP) gravity, gives rise to a
potentially observable anomaly in the solar system: all planets would exhibit a
common anomalous precession, dw/dt, in excess of the prediction of General
Relativity. We have used the Planetary Ephemeris Program (PEP) along with
planetary radar and radio tracking data to set a constraint of |dw/dt| < 0.02
arcseconds per century on the presence of any such common precession. This
sensitivity falls short of that needed to detect the estimated universal
precession of |dw/dt| = 5e-4 arcseconds per century expected in the DGP
scenario. We discuss the fact that ranging data between objects that orbit in a
common plane cannot constrain the DGP scenario. It is only through the relative
inclinations of the planetary orbital planes that solar system ranging data
have sensitivity to the DGP-like effect of universal precession. In addition,
we illustrate the importance of performing a numerical evaluation of the
sensitivity of the data set and model to any perturbative precession.Comment: 9 pages, 2 figures, accepted for publication in Phys. Rev.
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Brief psychotherapy for depression: a systematic review and meta-analysis
Objective: Because evidence-based psychotherapies of 12 to 20 sessions can be perceived as too lengthy and time intensive for the treatment of depression in primary care, a number of studies have examined abbreviated psychotherapy protocols. The purpose of this study was to conduct a systematic review and meta-analysis to determine the efficacy of brief psychotherapy (i.e., < 8 sessions) for depression.
Methods: We used combined literature searches in PubMed, EMBASE, PsycINFO, and an Internet-accessible database of clinical trials of psychotherapy to conduct two systematic searches: one for existing systematic reviews and another for randomized controlled trials (RCTs). Included studies examined evidence-based psychotherapy(s) of eight or fewer sessions, focused on adults with depression, contained an acceptable control condition, were published in English, and used validated measures of depressive symptoms.
Results: We retained 2 systematic reviews and 15 RCTs evaluating cognitive behavioral therapy, problem-solving therapy, and mindfulness-based cognitive therapy. The systematic reviews found brief psychotherapies to be more efficacious than control, with effect sizes ranging from −0.33 to −0.25. Our meta-analysis found six to eight sessions of cognitive behavioral therapy to be more efficacious than control (ES −0.42, 95% CI −0.74 to −0.10, I2 = 56%). A sensitivity analysis controlled for statistical heterogeneity but showed smaller treatment effects (ES −0.24, 95% CI −0.42 to −0.06, I2 = 0%).
Conclusions: Depression can be efficaciously treated with six to eight sessions of psychotherapy, particularly cognitive behavioral therapy and problem-solving therapy. Access to non-pharmacologic treatments for depression could be improved by training healthcare providers to deliver brief psychotherapies
Re-Engineering Systems for the Treatment of Depression in Primary Care: Cluster Randomised Controlled Trial
Objective: To test the effectiveness of an evidence based model for management of depression in primary care with support from quality improvement resources
Advocating Affordable Housing in New Hampshire: The Amicus Curiae Brief of the American Planning Association in Wayne Britton v. Town of Chester
In June 1990, The American Planning Association, a national Washington, D.C. based non-profit association of 27,000 professional planners, elected and appointed planning officials, and citizens interested in improving urban and rural planning filed this amicus curiae brief with the New Hampshire Supreme Court. The case on appeal is Wayne Britton v. Town of Chester, No. 85-E-342 (N.H. Super. Ct. June 27, 1989), brought by a builder/developer and low-income plaintiffs in need of affordable housing in Chester, New Hampshire
2007 Focused update of the ACC/AHA/SCAI 2005 guideline update for percutaneous coronary intervention: A report of the American College of Cardiology/American Heart Association task force on practice guidelines
Selected late-breaking clinical trials presented at the 2005 and 2006 annual scientific meetings of the ACC, AHA, and European Society of Cardiology, as well as selected other data, were reviewed by the standing guideline writing committee along with the parent Task Force and other experts to identify those trials and other key data that might impact guideline recommendations. On the basis of the criteria/considerations noted above, recent trial data and other clinical information were considered important enough to prompt a focused update of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention
2007 Focused Update of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines
"Selected late-breaking clinical trials presented at the 2005 and 2006 annual scientific meetings of the ACC, AHA, and European Society of Cardiology, as well as selected other data, were reviewed by the standing guideline writing committee along with the parent Task Force and other experts to identify those trials and other key data that might impact guideline recommendations. On the basis of the criteria/considerations noted above, recent trial data and other clinical information were considered important enough to prompt a focused update of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention (3–13). To provide clinicians with a comprehensive set of data, whenever possible, the exact event rates in various treatment arms of clinical trials are presented to permit calculation of the absolute risk difference (ARD) and number needed to treat (NNT) or harm (NNH); the relative treatment effects are described either as odds ratio (OR), relative risk (RR), or hazard ratio (HR), depending on the format in the original publication. Consult the full-text version or executive summary of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention for policy on clinical areas not covered by the focused update (13a). Individual recommendations updated in this focused update will be incorporated into future revisions and/or updates of the full-text guidelines.
Synthesis and Evaluation of 11C-Labeled Triazolones as Probes for Imaging Fatty Acid Synthase Expression by Positron Emission Tomography
Cancer cells require lipids to fulfill energetic, proliferative, and signaling requirements. Even though these cells can take up exogenous fatty acids, the majority exhibit a dependency on de novo fatty acid synthesis. Fatty acid synthase (FASN) is the rate-limiting enzyme in this process. Expression and activity of FASN is elevated in multiple cancers, where it correlates with disease progression and poor prognosis. These observations have sparked interest in developing methods of detecting FASN expression in vivo. One promising approach is the imaging of radiolabeled molecular probes targeting FASN by positron emission tomography (PET). However, although [11C]acetate uptake by prostate cancer cells correlates with FASN expression, no FASN-specific PET probes currently exist. Our aim was to synthesize and evaluate a series of small molecule triazolones based on GSK2194069, an FASN inhibitor with IC50 = 7.7 ± 4.1 nM, for PET imaging of FASN expression. These triazolones were labeled with carbon-11 in good yield and excellent radiochemical purity, and binding to FASN-positive LNCaP cells was significantly higher than FASN-negative PC3 cells. Despite these promising characteristics, however, these molecules exhibited poor in vivo pharmacokinetics and were predominantly retained in lymph nodes and the hepatobiliary system. Future studies will seek to identify structural modifications that improve tumor targeting while maintaining the excretion profile of these first-generation 11C-methyltriazolones
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